drivers/gpu/drm/msm/msm_gem.c

   1 /*
   2  * Copyright (C) 2013 Red Hat
   3  * Author: Rob Clark <robdclark@gmail.com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 as published by
   7  * the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12  * more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along with
  15  * this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #include <linux/spinlock.h>
  19 #include <linux/shmem_fs.h>
  20 #include <linux/dma-buf.h>
  21
  22 #include "msm_drv.h"
  23 #include "msm_gem.h"
  24 #include "msm_gpu.h"
  25 #include "msm_mmu.h"
  26
  27 static dma_addr_t physaddr(struct drm_gem_object *obj)
  28 {
  29         struct msm_gem_object *msm_obj = to_msm_bo(obj);
  30         struct msm_drm_private *priv = obj->dev->dev_private;
  31         return (((dma_addr_t)msm_obj->vram_node->start) << PAGE_SHIFT) +
  32                         priv->vram.paddr;
  33 }
  34
  35 static bool use_pages(struct drm_gem_object *obj)
  36 {
  37         struct msm_gem_object *msm_obj = to_msm_bo(obj);
  38         return !msm_obj->vram_node;
  39 }
  40
  41 /* allocate pages from VRAM carveout, used when no IOMMU: */
  42 static struct page **get_pages_vram(struct drm_gem_object *obj,
  43                 int npages)
  44 {
  45         struct msm_gem_object *msm_obj = to_msm_bo(obj);
  46         struct msm_drm_private *priv = obj->dev->dev_private;
  47         dma_addr_t paddr;
  48         struct page **p;
  49         int ret, i;
  50
  51         p = drm_malloc_ab(npages, sizeof(struct page *));
  52         if (!p)
  53                 return ERR_PTR(-ENOMEM);
  54
  55         ret = drm_mm_insert_node(&priv->vram.mm, msm_obj->vram_node,
  56                         npages, 0, DRM_MM_SEARCH_DEFAULT);
  57         if (ret) {
  58                 drm_free_large(p);
  59                 return ERR_PTR(ret);
  60         }
  61
  62         paddr = physaddr(obj);
  63         for (i = 0; i < npages; i++) {
  64                 p[i] = phys_to_page(paddr);
  65                 paddr += PAGE_SIZE;
  66         }
  67
  68         return p;
  69 }
  70
  71 /* called with dev->struct_mutex held */
  72 static struct page **get_pages(struct drm_gem_object *obj)
  73 {
  74         struct msm_gem_object *msm_obj = to_msm_bo(obj);
  75
  76         if (!msm_obj->pages) {
  77                 struct drm_device *dev = obj->dev;
  78                 struct page **p;
  79                 int npages = obj->size >> PAGE_SHIFT;
  80
  81                 if (use_pages(obj))
  82                         p = drm_gem_get_pages(obj);
  83                 else
  84                         p = get_pages_vram(obj, npages);
  85
  86                 if (IS_ERR(p)) {
  87                         dev_err(dev->dev, "could not get pages: %ld\n",
  88                                         PTR_ERR(p));
  89                         return p;
  90                 }
  91
  92                 msm_obj->sgt = drm_prime_pages_to_sg(p, npages);
  93                 if (IS_ERR(msm_obj->sgt)) {
  94                         dev_err(dev->dev, "failed to allocate sgt\n");
  95                         return ERR_CAST(msm_obj->sgt);
  96                 }
  97
  98                 msm_obj->pages = p;
  99
 100                 /* For non-cached buffers, ensure the new pages are clean
 101                  * because display controller, GPU, etc. are not coherent:
 102                  */
 103                 if (msm_obj->flags & (MSM_BO_WC|MSM_BO_UNCACHED))
 104                         dma_map_sg(dev->dev, msm_obj->sgt->sgl,
 105                                         msm_obj->sgt->nents, DMA_BIDIRECTIONAL);
 106         }
 107
 108         return msm_obj->pages;
 109 }
 110
 111 static void put_pages(struct drm_gem_object *obj)
 112 {
 113         struct msm_gem_object *msm_obj = to_msm_bo(obj);
 114
 115         if (msm_obj->pages) {
 116                 /* For non-cached buffers, ensure the new pages are clean
 117                  * because display controller, GPU, etc. are not coherent:
 118                  */
 119                 if (msm_obj->flags & (MSM_BO_WC|MSM_BO_UNCACHED))
 120                         dma_unmap_sg(obj->dev->dev, msm_obj->sgt->sgl,
 121                                         msm_obj->sgt->nents, DMA_BIDIRECTIONAL);
 122                 sg_free_table(msm_obj->sgt);
 123                 kfree(msm_obj->sgt);
 124
 125                 if (use_pages(obj))
 126                         drm_gem_put_pages(obj, msm_obj->pages, true, false);
 127                 else {
 128                         drm_mm_remove_node(msm_obj->vram_node);
 129                         drm_free_large(msm_obj->pages);
 130                 }
 131
 132                 msm_obj->pages = NULL;
 133         }
 134 }
 135
 136 struct page **msm_gem_get_pages(struct drm_gem_object *obj)
 137 {
 138         struct drm_device *dev = obj->dev;
 139         struct page **p;
 140         mutex_lock(&dev->struct_mutex);
 141         p = get_pages(obj);
 142         mutex_unlock(&dev->struct_mutex);
 143         return p;
 144 }
 145
 146 void msm_gem_put_pages(struct drm_gem_object *obj)
 147 {
 148         /* when we start tracking the pin count, then do something here */
 149 }
 150
 151 int msm_gem_mmap_obj(struct drm_gem_object *obj,
 152                 struct vm_area_struct *vma)
 153 {
 154         struct msm_gem_object *msm_obj = to_msm_bo(obj);
 155
 156         vma->vm_flags &= ~VM_PFNMAP;
 157         vma->vm_flags |= VM_MIXEDMAP;
 158
 159         if (msm_obj->flags & MSM_BO_WC) {
 160                 vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags));
 161         } else if (msm_obj->flags & MSM_BO_UNCACHED) {
 162                 vma->vm_page_prot = pgprot_noncached(vm_get_page_prot(vma->vm_flags));
 163         } else {
 164                 /*
 165                  * Shunt off cached objs to shmem file so they have their own
 166                  * address_space (so unmap_mapping_range does what we want,
 167                  * in particular in the case of mmap'd dmabufs)
 168                  */
 169                 fput(vma->vm_file);
 170                 get_file(obj->filp);
 171                 vma->vm_pgoff = 0;
 172                 vma->vm_file  = obj->filp;
 173
 174                 vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
 175         }
 176
 177         return 0;
 178 }
 179
 180 int msm_gem_mmap(struct file *filp, struct vm_area_struct *vma)
 181 {
 182         int ret;
 183
 184         ret = drm_gem_mmap(filp, vma);
 185         if (ret) {
 186                 DBG("mmap failed: %d", ret);
 187                 return ret;
 188         }
 189
 190         return msm_gem_mmap_obj(vma->vm_private_data, vma);
 191 }
 192
 193 int msm_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 194 {
 195         struct drm_gem_object *obj = vma->vm_private_data;
 196         struct drm_device *dev = obj->dev;
 197         struct page **pages;
 198         unsigned long pfn;
 199         pgoff_t pgoff;
 200         int ret;
 201
 202         /* Make sure we don't parallel update on a fault, nor move or remove
 203          * something from beneath our feet
 204          */
 205         ret = mutex_lock_interruptible(&dev->struct_mutex);
 206         if (ret)
 207                 goto out;
 208
 209         /* make sure we have pages attached now */
 210         pages = get_pages(obj);
 211         if (IS_ERR(pages)) {
 212                 ret = PTR_ERR(pages);
 213                 goto out_unlock;
 214         }
 215
 216         /* We don't use vmf->pgoff since that has the fake offset: */
 217         pgoff = ((unsigned long)vmf->virtual_address -
 218                         vma->vm_start) >> PAGE_SHIFT;
 219
 220         pfn = page_to_pfn(pages[pgoff]);
 221
 222         VERB("Inserting %p pfn %lx, pa %lx", vmf->virtual_address,
 223                         pfn, pfn << PAGE_SHIFT);
 224
 225         ret = vm_insert_mixed(vma, (unsigned long)vmf->virtual_address, pfn);
 226
 227 out_unlock:
 228         mutex_unlock(&dev->struct_mutex);
 229 out:
 230         switch (ret) {
 231         case -EAGAIN:
 232         case 0:
 233         case -ERESTARTSYS:
 234         case -EINTR:
 235         case -EBUSY:
 236                 /*
 237                  * EBUSY is ok: this just means that another thread
 238                  * already did the job.
 239                  */
 240                 return VM_FAULT_NOPAGE;
 241         case -ENOMEM:
 242                 return VM_FAULT_OOM;
 243         default:
 244                 return VM_FAULT_SIGBUS;
 245         }
 246 }
 247
 248 /** get mmap offset */
 249 static uint64_t mmap_offset(struct drm_gem_object *obj)
 250 {
 251         struct drm_device *dev = obj->dev;
 252         int ret;
 253
 254         WARN_ON(!mutex_is_locked(&dev->struct_mutex));
 255
 256         /* Make it mmapable */
 257         ret = drm_gem_create_mmap_offset(obj);
 258
 259         if (ret) {
 260                 dev_err(dev->dev, "could not allocate mmap offset\n");
 261                 return 0;
 262         }
 263
 264         return drm_vma_node_offset_addr(&obj->vma_node);
 265 }
 266
 267 uint64_t msm_gem_mmap_offset(struct drm_gem_object *obj)
 268 {
 269         uint64_t offset;
 270         mutex_lock(&obj->dev->struct_mutex);
 271         offset = mmap_offset(obj);
 272         mutex_unlock(&obj->dev->struct_mutex);
 273         return offset;
 274 }
 275
 276 /* should be called under struct_mutex.. although it can be called
 277  * from atomic context without struct_mutex to acquire an extra
 278  * iova ref if you know one is already held.
 279  *
 280  * That means when I do eventually need to add support for unpinning
 281  * the refcnt counter needs to be atomic_t.
 282  */
 283 int msm_gem_get_iova_locked(struct drm_gem_object *obj, int id,
 284                 uint32_t *iova)
 285 {
 286         struct msm_gem_object *msm_obj = to_msm_bo(obj);
 287         int ret = 0;
 288
 289         if (!msm_obj->domain[id].iova) {
 290                 struct msm_drm_private *priv = obj->dev->dev_private;
 291                 struct page **pages = get_pages(obj);
 292
 293                 if (IS_ERR(pages))
 294                         return PTR_ERR(pages);
 295
 296                 if (iommu_present(&platform_bus_type)) {
 297                         struct msm_mmu *mmu = priv->mmus[id];
 298                         uint32_t offset;
 299
 300                         if (WARN_ON(!mmu))
 301                                 return -EINVAL;
 302
 303                         offset = (uint32_t)mmap_offset(obj);
 304                         ret = mmu->funcs->map(mmu, offset, msm_obj->sgt,
 305                                         obj->size, IOMMU_READ | IOMMU_WRITE);
 306                         msm_obj->domain[id].iova = offset;
 307                 } else {
 308                         msm_obj->domain[id].iova = physaddr(obj);
 309                 }
 310         }
 311
 312         if (!ret)
 313                 *iova = msm_obj->domain[id].iova;
 314
 315         return ret;
 316 }
 317
 318 /* get iova, taking a reference.  Should have a matching put */
 319 int msm_gem_get_iova(struct drm_gem_object *obj, int id, uint32_t *iova)
 320 {
 321         struct msm_gem_object *msm_obj = to_msm_bo(obj);
 322         int ret;
 323
 324         /* this is safe right now because we don't unmap until the
 325          * bo is deleted:
 326          */
 327         if (msm_obj->domain[id].iova) {
 328                 *iova = msm_obj->domain[id].iova;
 329                 return 0;
 330         }
 331
 332         mutex_lock(&obj->dev->struct_mutex);
 333         ret = msm_gem_get_iova_locked(obj, id, iova);
 334         mutex_unlock(&obj->dev->struct_mutex);
 335         return ret;
 336 }
 337
 338 /* get iova without taking a reference, used in places where you have
 339  * already done a 'msm_gem_get_iova()'.
 340  */
 341 uint32_t msm_gem_iova(struct drm_gem_object *obj, int id)
 342 {
 343         struct msm_gem_object *msm_obj = to_msm_bo(obj);
 344         WARN_ON(!msm_obj->domain[id].iova);
 345         return msm_obj->domain[id].iova;
 346 }
 347
 348 void msm_gem_put_iova(struct drm_gem_object *obj, int id)
 349 {
 350         // XXX TODO ..
 351         // NOTE: probably don't need a _locked() version.. we wouldn't
 352         // normally unmap here, but instead just mark that it could be
 353         // unmapped (if the iova refcnt drops to zero), but then later
 354         // if another _get_iova_locked() fails we can start unmapping
 355         // things that are no longer needed..
 356 }
 357
 358 int msm_gem_dumb_create(struct drm_file *file, struct drm_device *dev,
 359                 struct drm_mode_create_dumb *args)
 360 {
 361         args->pitch = align_pitch(args->width, args->bpp);
 362         args->size  = PAGE_ALIGN(args->pitch * args->height);
 363         return msm_gem_new_handle(dev, file, args->size,
 364                         MSM_BO_SCANOUT | MSM_BO_WC, &args->handle);
 365 }
 366
 367 int msm_gem_dumb_map_offset(struct drm_file *file, struct drm_device *dev,
 368                 uint32_t handle, uint64_t *offset)
 369 {
 370         struct drm_gem_object *obj;
 371         int ret = 0;
 372
 373         /* GEM does all our handle to object mapping */
 374         obj = drm_gem_object_lookup(dev, file, handle);
 375         if (obj == NULL) {
 376                 ret = -ENOENT;
 377                 goto fail;
 378         }
 379
 380         *offset = msm_gem_mmap_offset(obj);
 381
 382         drm_gem_object_unreference_unlocked(obj);
 383
 384 fail:
 385         return ret;
 386 }
 387
 388 void *msm_gem_vaddr_locked(struct drm_gem_object *obj)
 389 {
 390         struct msm_gem_object *msm_obj = to_msm_bo(obj);
 391         WARN_ON(!mutex_is_locked(&obj->dev->struct_mutex));
 392         if (!msm_obj->vaddr) {
 393                 struct page **pages = get_pages(obj);
 394                 if (IS_ERR(pages))
 395                         return ERR_CAST(pages);
 396                 msm_obj->vaddr = vmap(pages, obj->size >> PAGE_SHIFT,
 397                                 VM_MAP, pgprot_writecombine(PAGE_KERNEL));
 398         }
 399         return msm_obj->vaddr;
 400 }
 401
 402 void *msm_gem_vaddr(struct drm_gem_object *obj)
 403 {
 404         void *ret;
 405         mutex_lock(&obj->dev->struct_mutex);
 406         ret = msm_gem_vaddr_locked(obj);
 407         mutex_unlock(&obj->dev->struct_mutex);
 408         return ret;
 409 }
 410
 411 /* setup callback for when bo is no longer busy..
 412  * TODO probably want to differentiate read vs write..
 413  */
 414 int msm_gem_queue_inactive_cb(struct drm_gem_object *obj,
 415                 struct msm_fence_cb *cb)
 416 {
 417         struct msm_gem_object *msm_obj = to_msm_bo(obj);
 418         uint32_t fence = msm_gem_fence(msm_obj,
 419                         MSM_PREP_READ | MSM_PREP_WRITE);
 420         return msm_queue_fence_cb(obj->dev, cb, fence);
 421 }
 422
 423 void msm_gem_move_to_active(struct drm_gem_object *obj,
 424                 struct msm_gpu *gpu, bool write, uint32_t fence)
 425 {
 426         struct msm_gem_object *msm_obj = to_msm_bo(obj);
 427         msm_obj->gpu = gpu;
 428         if (write)
 429                 msm_obj->write_fence = fence;
 430         else
 431                 msm_obj->read_fence = fence;
 432         list_del_init(&msm_obj->mm_list);
 433         list_add_tail(&msm_obj->mm_list, &gpu->active_list);
 434 }
 435
 436 void msm_gem_move_to_inactive(struct drm_gem_object *obj)
 437 {
 438         struct drm_device *dev = obj->dev;
 439         struct msm_drm_private *priv = dev->dev_private;
 440         struct msm_gem_object *msm_obj = to_msm_bo(obj);
 441
 442         WARN_ON(!mutex_is_locked(&dev->struct_mutex));
 443
 444         msm_obj->gpu = NULL;
 445         msm_obj->read_fence = 0;
 446         msm_obj->write_fence = 0;
 447         list_del_init(&msm_obj->mm_list);
 448         list_add_tail(&msm_obj->mm_list, &priv->inactive_list);
 449 }
 450
 451 int msm_gem_cpu_prep(struct drm_gem_object *obj, uint32_t op, ktime_t *timeout)
 452 {
 453         struct drm_device *dev = obj->dev;
 454         struct msm_gem_object *msm_obj = to_msm_bo(obj);
 455         int ret = 0;
 456
 457         if (is_active(msm_obj)) {
 458                 uint32_t fence = msm_gem_fence(msm_obj, op);
 459
 460                 if (op & MSM_PREP_NOSYNC)
 461                         timeout = NULL;
 462
 463                 ret = msm_wait_fence(dev, fence, timeout, true);
 464         }
 465
 466         /* TODO cache maintenance */
 467
 468         return ret;
 469 }
 470
 471 int msm_gem_cpu_fini(struct drm_gem_object *obj)
 472 {
 473         /* TODO cache maintenance */
 474         return 0;
 475 }
 476
 477 #ifdef CONFIG_DEBUG_FS
 478 void msm_gem_describe(struct drm_gem_object *obj, struct seq_file *m)
 479 {
 480         struct drm_device *dev = obj->dev;
 481         struct msm_gem_object *msm_obj = to_msm_bo(obj);
 482         uint64_t off = drm_vma_node_start(&obj->vma_node);
 483
 484         WARN_ON(!mutex_is_locked(&dev->struct_mutex));
 485         seq_printf(m, "%08x: %c(r=%u,w=%u) %2d (%2d) %08llx %p %zu\n",
 486                         msm_obj->flags, is_active(msm_obj) ? 'A' : 'I',
 487                         msm_obj->read_fence, msm_obj->write_fence,
 488                         obj->name, obj->refcount.refcount.counter,
 489                         off, msm_obj->vaddr, obj->size);
 490 }
 491
 492 void msm_gem_describe_objects(struct list_head *list, struct seq_file *m)
 493 {
 494         struct msm_gem_object *msm_obj;
 495         int count = 0;
 496         size_t size = 0;
 497
 498         list_for_each_entry(msm_obj, list, mm_list) {
 499                 struct drm_gem_object *obj = &msm_obj->base;
 500                 seq_printf(m, "   ");
 501                 msm_gem_describe(obj, m);
 502                 count++;
 503                 size += obj->size;
 504         }
 505
 506         seq_printf(m, "Total %d objects, %zu bytes\n", count, size);
 507 }
 508 #endif
 509
 510 void msm_gem_free_object(struct drm_gem_object *obj)
 511 {
 512         struct drm_device *dev = obj->dev;
 513         struct msm_drm_private *priv = obj->dev->dev_private;
 514         struct msm_gem_object *msm_obj = to_msm_bo(obj);
 515         int id;
 516
 517         WARN_ON(!mutex_is_locked(&dev->struct_mutex));
 518
 519         /* object should not be on active list: */
 520         WARN_ON(is_active(msm_obj));
 521
 522         list_del(&msm_obj->mm_list);
 523
 524         for (id = 0; id < ARRAY_SIZE(msm_obj->domain); id++) {
 525                 struct msm_mmu *mmu = priv->mmus[id];
 526                 if (mmu && msm_obj->domain[id].iova) {
 527                         uint32_t offset = msm_obj->domain[id].iova;
 528                         mmu->funcs->unmap(mmu, offset, msm_obj->sgt, obj->size);
 529                 }
 530         }
 531
 532         if (obj->import_attach) {
 533                 if (msm_obj->vaddr)
 534                         dma_buf_vunmap(obj->import_attach->dmabuf, msm_obj->vaddr);
 535
 536                 /* Don't drop the pages for imported dmabuf, as they are not
 537                  * ours, just free the array we allocated:
 538                  */
 539                 if (msm_obj->pages)
 540                         drm_free_large(msm_obj->pages);
 541
 542                 drm_prime_gem_destroy(obj, msm_obj->sgt);
 543         } else {
 544                 vunmap(msm_obj->vaddr);
 545                 put_pages(obj);
 546         }
 547
 548         if (msm_obj->resv == &msm_obj->_resv)
 549                 reservation_object_fini(msm_obj->resv);
 550
 551         drm_gem_object_release(obj);
 552
 553         kfree(msm_obj);
 554 }
 555
 556 /* convenience method to construct a GEM buffer object, and userspace handle */
 557 int msm_gem_new_handle(struct drm_device *dev, struct drm_file *file,
 558                 uint32_t size, uint32_t flags, uint32_t *handle)
 559 {
 560         struct drm_gem_object *obj;
 561         int ret;
 562
 563         ret = mutex_lock_interruptible(&dev->struct_mutex);
 564         if (ret)
 565                 return ret;
 566
 567         obj = msm_gem_new(dev, size, flags);
 568
 569         mutex_unlock(&dev->struct_mutex);
 570
 571         if (IS_ERR(obj))
 572                 return PTR_ERR(obj);
 573
 574         ret = drm_gem_handle_create(file, obj, handle);
 575
 576         /* drop reference from allocate - handle holds it now */
 577         drm_gem_object_unreference_unlocked(obj);
 578
 579         return ret;
 580 }
 581
 582 static int msm_gem_new_impl(struct drm_device *dev,
 583                 uint32_t size, uint32_t flags,
 584                 struct drm_gem_object **obj)
 585 {
 586         struct msm_drm_private *priv = dev->dev_private;
 587         struct msm_gem_object *msm_obj;
 588         unsigned sz;
 589         bool use_vram = false;
 590
 591         switch (flags & MSM_BO_CACHE_MASK) {
 592         case MSM_BO_UNCACHED:
 593         case MSM_BO_CACHED:
 594         case MSM_BO_WC:
 595                 break;
 596         default:
 597                 dev_err(dev->dev, "invalid cache flag: %x\n",
 598                                 (flags & MSM_BO_CACHE_MASK));
 599                 return -EINVAL;
 600         }
 601
 602         if (!iommu_present(&platform_bus_type))
 603                 use_vram = true;
 604         else if ((flags & MSM_BO_STOLEN) && priv->vram.size)
 605                 use_vram = true;
 606
 607         if (WARN_ON(use_vram && !priv->vram.size))
 608                 return -EINVAL;
 609
 610         sz = sizeof(*msm_obj);
 611         if (use_vram)
 612                 sz += sizeof(struct drm_mm_node);
 613
 614         msm_obj = kzalloc(sz, GFP_KERNEL);
 615         if (!msm_obj)
 616                 return -ENOMEM;
 617
 618         if (use_vram)
 619                 msm_obj->vram_node = (void *)&msm_obj[1];
 620
 621         msm_obj->flags = flags;
 622
 623         msm_obj->resv = &msm_obj->_resv;
 624         reservation_object_init(msm_obj->resv);
 625
 626         INIT_LIST_HEAD(&msm_obj->submit_entry);
 627         list_add_tail(&msm_obj->mm_list, &priv->inactive_list);
 628
 629         *obj = &msm_obj->base;
 630
 631         return 0;
 632 }
 633
 634 struct drm_gem_object *msm_gem_new(struct drm_device *dev,
 635                 uint32_t size, uint32_t flags)
 636 {
 637         struct drm_gem_object *obj = NULL;
 638         int ret;
 639
 640         WARN_ON(!mutex_is_locked(&dev->struct_mutex));
 641
 642         size = PAGE_ALIGN(size);
 643
 644         ret = msm_gem_new_impl(dev, size, flags, &obj);
 645         if (ret)
 646                 goto fail;
 647
 648         if (use_pages(obj)) {
 649                 ret = drm_gem_object_init(dev, obj, size);
 650                 if (ret)
 651                         goto fail;
 652         } else {
 653                 drm_gem_private_object_init(dev, obj, size);
 654         }
 655
 656         return obj;
 657
 658 fail:
 659         if (obj)
 660                 drm_gem_object_unreference(obj);
 661
 662         return ERR_PTR(ret);
 663 }
 664
 665 struct drm_gem_object *msm_gem_import(struct drm_device *dev,
 666                 uint32_t size, struct sg_table *sgt)
 667 {
 668         struct msm_gem_object *msm_obj;
 669         struct drm_gem_object *obj;
 670         int ret, npages;
 671
 672         /* if we don't have IOMMU, don't bother pretending we can import: */
 673         if (!iommu_present(&platform_bus_type)) {
 674                 dev_err(dev->dev, "cannot import without IOMMU\n");
 675                 return ERR_PTR(-EINVAL);
 676         }
 677
 678         size = PAGE_ALIGN(size);
 679
 680         ret = msm_gem_new_impl(dev, size, MSM_BO_WC, &obj);
 681         if (ret)
 682                 goto fail;
 683
 684         drm_gem_private_object_init(dev, obj, size);
 685
 686         npages = size / PAGE_SIZE;
 687
 688         msm_obj = to_msm_bo(obj);
 689         msm_obj->sgt = sgt;
 690         msm_obj->pages = drm_malloc_ab(npages, sizeof(struct page *));
 691         if (!msm_obj->pages) {
 692                 ret = -ENOMEM;
 693                 goto fail;
 694         }
 695
 696         ret = drm_prime_sg_to_page_addr_arrays(sgt, msm_obj->pages, NULL, npages);
 697         if (ret)
 698                 goto fail;
 699
 700         return obj;
 701
 702 fail:
 703         if (obj)
 704                 drm_gem_object_unreference_unlocked(obj);
 705
 706         return ERR_PTR(ret);
 707 }