drivers/gpu/drm/vc4/vc4_bo.c

   1 /*
   2  *  Copyright © 2015 Broadcom
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  */
   8
   9 /* DOC: VC4 GEM BO management support.
  10  *
  11  * The VC4 GPU architecture (both scanout and rendering) has direct
  12  * access to system memory with no MMU in between.  To support it, we
  13  * use the GEM CMA helper functions to allocate contiguous ranges of
  14  * physical memory for our BOs.
  15  *
  16  * Since the CMA allocator is very slow, we keep a cache of recently
  17  * freed BOs around so that the kernel's allocation of objects for 3D
  18  * rendering can return quickly.
  19  */
  20
  21 #include "vc4_drv.h"
  22 #include "uapi/drm/vc4_drm.h"
  23
  24 static void vc4_bo_stats_dump(struct vc4_dev *vc4)
  25 {
  26         DRM_INFO("num bos allocated: %d\n",
  27                  vc4->bo_stats.num_allocated);
  28         DRM_INFO("size bos allocated: %dkb\n",
  29                  vc4->bo_stats.size_allocated / 1024);
  30         DRM_INFO("num bos used: %d\n",
  31                  vc4->bo_stats.num_allocated - vc4->bo_stats.num_cached);
  32         DRM_INFO("size bos used: %dkb\n",
  33                  (vc4->bo_stats.size_allocated -
  34                   vc4->bo_stats.size_cached) / 1024);
  35         DRM_INFO("num bos cached: %d\n",
  36                  vc4->bo_stats.num_cached);
  37         DRM_INFO("size bos cached: %dkb\n",
  38                  vc4->bo_stats.size_cached / 1024);
  39 }
  40
  41 #ifdef CONFIG_DEBUG_FS
  42 int vc4_bo_stats_debugfs(struct seq_file *m, void *unused)
  43 {
  44         struct drm_info_node *node = (struct drm_info_node *)m->private;
  45         struct drm_device *dev = node->minor->dev;
  46         struct vc4_dev *vc4 = to_vc4_dev(dev);
  47         struct vc4_bo_stats stats;
  48
  49         /* Take a snapshot of the current stats with the lock held. */
  50         mutex_lock(&vc4->bo_lock);
  51         stats = vc4->bo_stats;
  52         mutex_unlock(&vc4->bo_lock);
  53
  54         seq_printf(m, "num bos allocated: %d\n",
  55                    stats.num_allocated);
  56         seq_printf(m, "size bos allocated: %dkb\n",
  57                    stats.size_allocated / 1024);
  58         seq_printf(m, "num bos used: %d\n",
  59                    stats.num_allocated - stats.num_cached);
  60         seq_printf(m, "size bos used: %dkb\n",
  61                    (stats.size_allocated - stats.size_cached) / 1024);
  62         seq_printf(m, "num bos cached: %d\n",
  63                    stats.num_cached);
  64         seq_printf(m, "size bos cached: %dkb\n",
  65                    stats.size_cached / 1024);
  66
  67         return 0;
  68 }
  69 #endif
  70
  71 static uint32_t bo_page_index(size_t size)
  72 {
  73         return (size / PAGE_SIZE) - 1;
  74 }
  75
  76 /* Must be called with bo_lock held. */
  77 static void vc4_bo_destroy(struct vc4_bo *bo)
  78 {
  79         struct drm_gem_object *obj = &bo->base.base;
  80         struct vc4_dev *vc4 = to_vc4_dev(obj->dev);
  81
  82         if (bo->validated_shader) {
  83                 kfree(bo->validated_shader->uniform_addr_offsets);
  84                 kfree(bo->validated_shader->texture_samples);
  85                 kfree(bo->validated_shader);
  86                 bo->validated_shader = NULL;
  87         }
  88
  89         vc4->bo_stats.num_allocated--;
  90         vc4->bo_stats.size_allocated -= obj->size;
  91         drm_gem_cma_free_object(obj);
  92 }
  93
  94 /* Must be called with bo_lock held. */
  95 static void vc4_bo_remove_from_cache(struct vc4_bo *bo)
  96 {
  97         struct drm_gem_object *obj = &bo->base.base;
  98         struct vc4_dev *vc4 = to_vc4_dev(obj->dev);
  99
 100         vc4->bo_stats.num_cached--;
 101         vc4->bo_stats.size_cached -= obj->size;
 102
 103         list_del(&bo->unref_head);
 104         list_del(&bo->size_head);
 105 }
 106
 107 static struct list_head *vc4_get_cache_list_for_size(struct drm_device *dev,
 108                                                      size_t size)
 109 {
 110         struct vc4_dev *vc4 = to_vc4_dev(dev);
 111         uint32_t page_index = bo_page_index(size);
 112
 113         if (vc4->bo_cache.size_list_size <= page_index) {
 114                 uint32_t new_size = max(vc4->bo_cache.size_list_size * 2,
 115                                         page_index + 1);
 116                 struct list_head *new_list;
 117                 uint32_t i;
 118
 119                 new_list = kmalloc_array(new_size, sizeof(struct list_head),
 120                                          GFP_KERNEL);
 121                 if (!new_list)
 122                         return NULL;
 123
 124                 /* Rebase the old cached BO lists to their new list
 125                  * head locations.
 126                  */
 127                 for (i = 0; i < vc4->bo_cache.size_list_size; i++) {
 128                         struct list_head *old_list =
 129                                 &vc4->bo_cache.size_list[i];
 130
 131                         if (list_empty(old_list))
 132                                 INIT_LIST_HEAD(&new_list[i]);
 133                         else
 134                                 list_replace(old_list, &new_list[i]);
 135                 }
 136                 /* And initialize the brand new BO list heads. */
 137                 for (i = vc4->bo_cache.size_list_size; i < new_size; i++)
 138                         INIT_LIST_HEAD(&new_list[i]);
 139
 140                 kfree(vc4->bo_cache.size_list);
 141                 vc4->bo_cache.size_list = new_list;
 142                 vc4->bo_cache.size_list_size = new_size;
 143         }
 144
 145         return &vc4->bo_cache.size_list[page_index];
 146 }
 147
 148 static void vc4_bo_cache_purge(struct drm_device *dev)
 149 {
 150         struct vc4_dev *vc4 = to_vc4_dev(dev);
 151
 152         mutex_lock(&vc4->bo_lock);
 153         while (!list_empty(&vc4->bo_cache.time_list)) {
 154                 struct vc4_bo *bo = list_last_entry(&vc4->bo_cache.time_list,
 155                                                     struct vc4_bo, unref_head);
 156                 vc4_bo_remove_from_cache(bo);
 157                 vc4_bo_destroy(bo);
 158         }
 159         mutex_unlock(&vc4->bo_lock);
 160 }
 161
 162 static struct vc4_bo *vc4_bo_get_from_cache(struct drm_device *dev,
 163                                             uint32_t size)
 164 {
 165         struct vc4_dev *vc4 = to_vc4_dev(dev);
 166         uint32_t page_index = bo_page_index(size);
 167         struct vc4_bo *bo = NULL;
 168
 169         size = roundup(size, PAGE_SIZE);
 170
 171         mutex_lock(&vc4->bo_lock);
 172         if (page_index >= vc4->bo_cache.size_list_size)
 173                 goto out;
 174
 175         if (list_empty(&vc4->bo_cache.size_list[page_index]))
 176                 goto out;
 177
 178         bo = list_first_entry(&vc4->bo_cache.size_list[page_index],
 179                               struct vc4_bo, size_head);
 180         vc4_bo_remove_from_cache(bo);
 181         kref_init(&bo->base.base.refcount);
 182
 183 out:
 184         mutex_unlock(&vc4->bo_lock);
 185         return bo;
 186 }
 187
 188 /**
 189  * vc4_gem_create_object - Implementation of driver->gem_create_object.
 190  *
 191  * This lets the CMA helpers allocate object structs for us, and keep
 192  * our BO stats correct.
 193  */
 194 struct drm_gem_object *vc4_create_object(struct drm_device *dev, size_t size)
 195 {
 196         struct vc4_dev *vc4 = to_vc4_dev(dev);
 197         struct vc4_bo *bo;
 198
 199         bo = kzalloc(sizeof(*bo), GFP_KERNEL);
 200         if (!bo)
 201                 return ERR_PTR(-ENOMEM);
 202
 203         mutex_lock(&vc4->bo_lock);
 204         vc4->bo_stats.num_allocated++;
 205         vc4->bo_stats.size_allocated += size;
 206         mutex_unlock(&vc4->bo_lock);
 207
 208         return &bo->base.base;
 209 }
 210
 211 struct vc4_bo *vc4_bo_create(struct drm_device *dev, size_t unaligned_size,
 212                              bool from_cache)
 213 {
 214         size_t size = roundup(unaligned_size, PAGE_SIZE);
 215         struct vc4_dev *vc4 = to_vc4_dev(dev);
 216         struct drm_gem_cma_object *cma_obj;
 217
 218         if (size == 0)
 219                 return ERR_PTR(-EINVAL);
 220
 221         /* First, try to get a vc4_bo from the kernel BO cache. */
 222         if (from_cache) {
 223                 struct vc4_bo *bo = vc4_bo_get_from_cache(dev, size);
 224
 225                 if (bo)
 226                         return bo;
 227         }
 228
 229         cma_obj = drm_gem_cma_create(dev, size);
 230         if (IS_ERR(cma_obj)) {
 231                 /*
 232                  * If we've run out of CMA memory, kill the cache of
 233                  * CMA allocations we've got laying around and try again.
 234                  */
 235                 vc4_bo_cache_purge(dev);
 236
 237                 cma_obj = drm_gem_cma_create(dev, size);
 238                 if (IS_ERR(cma_obj)) {
 239                         DRM_ERROR("Failed to allocate from CMA:\n");
 240                         vc4_bo_stats_dump(vc4);
 241                         return ERR_PTR(-ENOMEM);
 242                 }
 243         }
 244
 245         return to_vc4_bo(&cma_obj->base);
 246 }
 247
 248 int vc4_dumb_create(struct drm_file *file_priv,
 249                     struct drm_device *dev,
 250                     struct drm_mode_create_dumb *args)
 251 {
 252         int min_pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
 253         struct vc4_bo *bo = NULL;
 254         int ret;
 255
 256         if (args->pitch < min_pitch)
 257                 args->pitch = min_pitch;
 258
 259         if (args->size < args->pitch * args->height)
 260                 args->size = args->pitch * args->height;
 261
 262         bo = vc4_bo_create(dev, args->size, false);
 263         if (IS_ERR(bo))
 264                 return PTR_ERR(bo);
 265
 266         ret = drm_gem_handle_create(file_priv, &bo->base.base, &args->handle);
 267         drm_gem_object_unreference_unlocked(&bo->base.base);
 268
 269         return ret;
 270 }
 271
 272 /* Must be called with bo_lock held. */
 273 static void vc4_bo_cache_free_old(struct drm_device *dev)
 274 {
 275         struct vc4_dev *vc4 = to_vc4_dev(dev);
 276         unsigned long expire_time = jiffies - msecs_to_jiffies(1000);
 277
 278         while (!list_empty(&vc4->bo_cache.time_list)) {
 279                 struct vc4_bo *bo = list_last_entry(&vc4->bo_cache.time_list,
 280                                                     struct vc4_bo, unref_head);
 281                 if (time_before(expire_time, bo->free_time)) {
 282                         mod_timer(&vc4->bo_cache.time_timer,
 283                                   round_jiffies_up(jiffies +
 284                                                    msecs_to_jiffies(1000)));
 285                         return;
 286                 }
 287
 288                 vc4_bo_remove_from_cache(bo);
 289                 vc4_bo_destroy(bo);
 290         }
 291 }
 292
 293 /* Called on the last userspace/kernel unreference of the BO.  Returns
 294  * it to the BO cache if possible, otherwise frees it.
 295  */
 296 void vc4_free_object(struct drm_gem_object *gem_bo)
 297 {
 298         struct drm_device *dev = gem_bo->dev;
 299         struct vc4_dev *vc4 = to_vc4_dev(dev);
 300         struct vc4_bo *bo = to_vc4_bo(gem_bo);
 301         struct list_head *cache_list;
 302
 303         mutex_lock(&vc4->bo_lock);
 304         /* If the object references someone else's memory, we can't cache it.
 305          */
 306         if (gem_bo->import_attach) {
 307                 vc4_bo_destroy(bo);
 308                 goto out;
 309         }
 310
 311         /* Don't cache if it was publicly named. */
 312         if (gem_bo->name) {
 313                 vc4_bo_destroy(bo);
 314                 goto out;
 315         }
 316
 317         /* If this object was partially constructed but CMA allocation
 318          * had failed, just free it.
 319          */
 320         if (!bo->base.vaddr) {
 321                 vc4_bo_destroy(bo);
 322                 goto out;
 323         }
 324
 325         cache_list = vc4_get_cache_list_for_size(dev, gem_bo->size);
 326         if (!cache_list) {
 327                 vc4_bo_destroy(bo);
 328                 goto out;
 329         }
 330
 331         if (bo->validated_shader) {
 332                 kfree(bo->validated_shader->uniform_addr_offsets);
 333                 kfree(bo->validated_shader->texture_samples);
 334                 kfree(bo->validated_shader);
 335                 bo->validated_shader = NULL;
 336         }
 337
 338         bo->free_time = jiffies;
 339         list_add(&bo->size_head, cache_list);
 340         list_add(&bo->unref_head, &vc4->bo_cache.time_list);
 341
 342         vc4->bo_stats.num_cached++;
 343         vc4->bo_stats.size_cached += gem_bo->size;
 344
 345         vc4_bo_cache_free_old(dev);
 346
 347 out:
 348         mutex_unlock(&vc4->bo_lock);
 349 }
 350
 351 static void vc4_bo_cache_time_work(struct work_struct *work)
 352 {
 353         struct vc4_dev *vc4 =
 354                 container_of(work, struct vc4_dev, bo_cache.time_work);
 355         struct drm_device *dev = vc4->dev;
 356
 357         mutex_lock(&vc4->bo_lock);
 358         vc4_bo_cache_free_old(dev);
 359         mutex_unlock(&vc4->bo_lock);
 360 }
 361
 362 static void vc4_bo_cache_time_timer(unsigned long data)
 363 {
 364         struct drm_device *dev = (struct drm_device *)data;
 365         struct vc4_dev *vc4 = to_vc4_dev(dev);
 366
 367         schedule_work(&vc4->bo_cache.time_work);
 368 }
 369
 370 struct dma_buf *
 371 vc4_prime_export(struct drm_device *dev, struct drm_gem_object *obj, int flags)
 372 {
 373         struct vc4_bo *bo = to_vc4_bo(obj);
 374
 375         if (bo->validated_shader) {
 376                 DRM_ERROR("Attempting to export shader BO\n");
 377                 return ERR_PTR(-EINVAL);
 378         }
 379
 380         return drm_gem_prime_export(dev, obj, flags);
 381 }
 382
 383 int vc4_mmap(struct file *filp, struct vm_area_struct *vma)
 384 {
 385         struct drm_gem_object *gem_obj;
 386         struct vc4_bo *bo;
 387         int ret;
 388
 389         ret = drm_gem_mmap(filp, vma);
 390         if (ret)
 391                 return ret;
 392
 393         gem_obj = vma->vm_private_data;
 394         bo = to_vc4_bo(gem_obj);
 395
 396         if (bo->validated_shader && (vma->vm_flags & VM_WRITE)) {
 397                 DRM_ERROR("mmaping of shader BOs for writing not allowed.\n");
 398                 return -EINVAL;
 399         }
 400
 401         /*
 402          * Clear the VM_PFNMAP flag that was set by drm_gem_mmap(), and set the
 403          * vm_pgoff (used as a fake buffer offset by DRM) to 0 as we want to map
 404          * the whole buffer.
 405          */
 406         vma->vm_flags &= ~VM_PFNMAP;
 407         vma->vm_pgoff = 0;
 408
 409         ret = dma_mmap_wc(bo->base.base.dev->dev, vma, bo->base.vaddr,
 410                           bo->base.paddr, vma->vm_end - vma->vm_start);
 411         if (ret)
 412                 drm_gem_vm_close(vma);
 413
 414         return ret;
 415 }
 416
 417 int vc4_prime_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma)
 418 {
 419         struct vc4_bo *bo = to_vc4_bo(obj);
 420
 421         if (bo->validated_shader && (vma->vm_flags & VM_WRITE)) {
 422                 DRM_ERROR("mmaping of shader BOs for writing not allowed.\n");
 423                 return -EINVAL;
 424         }
 425
 426         return drm_gem_cma_prime_mmap(obj, vma);
 427 }
 428
 429 void *vc4_prime_vmap(struct drm_gem_object *obj)
 430 {
 431         struct vc4_bo *bo = to_vc4_bo(obj);
 432
 433         if (bo->validated_shader) {
 434                 DRM_ERROR("mmaping of shader BOs not allowed.\n");
 435                 return ERR_PTR(-EINVAL);
 436         }
 437
 438         return drm_gem_cma_prime_vmap(obj);
 439 }
 440
 441 int vc4_create_bo_ioctl(struct drm_device *dev, void *data,
 442                         struct drm_file *file_priv)
 443 {
 444         struct drm_vc4_create_bo *args = data;
 445         struct vc4_bo *bo = NULL;
 446         int ret;
 447
 448         /*
 449          * We can't allocate from the BO cache, because the BOs don't
 450          * get zeroed, and that might leak data between users.
 451          */
 452         bo = vc4_bo_create(dev, args->size, false);
 453         if (IS_ERR(bo))
 454                 return PTR_ERR(bo);
 455
 456         ret = drm_gem_handle_create(file_priv, &bo->base.base, &args->handle);
 457         drm_gem_object_unreference_unlocked(&bo->base.base);
 458
 459         return ret;
 460 }
 461
 462 int vc4_mmap_bo_ioctl(struct drm_device *dev, void *data,
 463                       struct drm_file *file_priv)
 464 {
 465         struct drm_vc4_mmap_bo *args = data;
 466         struct drm_gem_object *gem_obj;
 467
 468         gem_obj = drm_gem_object_lookup(file_priv, args->handle);
 469         if (!gem_obj) {
 470                 DRM_ERROR("Failed to look up GEM BO %d\n", args->handle);
 471                 return -EINVAL;
 472         }
 473
 474         /* The mmap offset was set up at BO allocation time. */
 475         args->offset = drm_vma_node_offset_addr(&gem_obj->vma_node);
 476
 477         drm_gem_object_unreference_unlocked(gem_obj);
 478         return 0;
 479 }
 480
 481 int
 482 vc4_create_shader_bo_ioctl(struct drm_device *dev, void *data,
 483                            struct drm_file *file_priv)
 484 {
 485         struct drm_vc4_create_shader_bo *args = data;
 486         struct vc4_bo *bo = NULL;
 487         int ret;
 488
 489         if (args->size == 0)
 490                 return -EINVAL;
 491
 492         if (args->size % sizeof(u64) != 0)
 493                 return -EINVAL;
 494
 495         if (args->flags != 0) {
 496                 DRM_INFO("Unknown flags set: 0x%08x\n", args->flags);
 497                 return -EINVAL;
 498         }
 499
 500         if (args->pad != 0) {
 501                 DRM_INFO("Pad set: 0x%08x\n", args->pad);
 502                 return -EINVAL;
 503         }
 504
 505         bo = vc4_bo_create(dev, args->size, true);
 506         if (IS_ERR(bo))
 507                 return PTR_ERR(bo);
 508
 509         if (copy_from_user(bo->base.vaddr,
 510                              (void __user *)(uintptr_t)args->data,
 511                              args->size)) {
 512                 ret = -EFAULT;
 513                 goto fail;
 514         }
 515         /* Clear the rest of the memory from allocating from the BO
 516          * cache.
 517          */
 518         memset(bo->base.vaddr + args->size, 0,
 519                bo->base.base.size - args->size);
 520
 521         bo->validated_shader = vc4_validate_shader(&bo->base);
 522         if (!bo->validated_shader) {
 523                 ret = -EINVAL;
 524                 goto fail;
 525         }
 526
 527         /* We have to create the handle after validation, to avoid
 528          * races for users to do doing things like mmap the shader BO.
 529          */
 530         ret = drm_gem_handle_create(file_priv, &bo->base.base, &args->handle);
 531
 532  fail:
 533         drm_gem_object_unreference_unlocked(&bo->base.base);
 534
 535         return ret;
 536 }
 537
 538 void vc4_bo_cache_init(struct drm_device *dev)
 539 {
 540         struct vc4_dev *vc4 = to_vc4_dev(dev);
 541
 542         mutex_init(&vc4->bo_lock);
 543
 544         INIT_LIST_HEAD(&vc4->bo_cache.time_list);
 545
 546         INIT_WORK(&vc4->bo_cache.time_work, vc4_bo_cache_time_work);
 547         setup_timer(&vc4->bo_cache.time_timer,
 548                     vc4_bo_cache_time_timer,
 549                     (unsigned long)dev);
 550 }
 551
 552 void vc4_bo_cache_destroy(struct drm_device *dev)
 553 {
 554         struct vc4_dev *vc4 = to_vc4_dev(dev);
 555
 556         del_timer(&vc4->bo_cache.time_timer);
 557         cancel_work_sync(&vc4->bo_cache.time_work);
 558
 559         vc4_bo_cache_purge(dev);
 560
 561         if (vc4->bo_stats.num_allocated) {
 562                 DRM_ERROR("Destroying BO cache while BOs still allocated:\n");
 563                 vc4_bo_stats_dump(vc4);
 564         }
 565 }