drivers/gpu/drm/i915/gem/i915_gem_object.c

   1 /*
   2  * Copyright © 2017 Intel Corporation
   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 DEALINGS
  21  * IN THE SOFTWARE.
  22  *
  23  */
  24
  25 #include <linux/sched/mm.h>
  26
  27 #include "display/intel_frontbuffer.h"
  28 #include "gt/intel_gt.h"
  29 #include "i915_drv.h"
  30 #include "i915_gem_clflush.h"
  31 #include "i915_gem_context.h"
  32 #include "i915_gem_mman.h"
  33 #include "i915_gem_object.h"
  34 #include "i915_globals.h"
  35 #include "i915_trace.h"
  36
  37 static struct i915_global_object {
  38         struct i915_global base;
  39         struct kmem_cache *slab_objects;
  40 } global;
  41
  42 static const struct drm_gem_object_funcs i915_gem_object_funcs;
  43
  44 struct drm_i915_gem_object *i915_gem_object_alloc(void)
  45 {
  46         struct drm_i915_gem_object *obj;
  47
  48         obj = kmem_cache_zalloc(global.slab_objects, GFP_KERNEL);
  49         if (!obj)
  50                 return NULL;
  51         obj->base.funcs = &i915_gem_object_funcs;
  52
  53         return obj;
  54 }
  55
  56 void i915_gem_object_free(struct drm_i915_gem_object *obj)
  57 {
  58         return kmem_cache_free(global.slab_objects, obj);
  59 }
  60
  61 void i915_gem_object_init(struct drm_i915_gem_object *obj,
  62                           const struct drm_i915_gem_object_ops *ops,
  63                           struct lock_class_key *key)
  64 {
  65         __mutex_init(&obj->mm.lock, ops->name ?: "obj->mm.lock", key);
  66
  67         spin_lock_init(&obj->vma.lock);
  68         INIT_LIST_HEAD(&obj->vma.list);
  69
  70         INIT_LIST_HEAD(&obj->mm.link);
  71
  72         INIT_LIST_HEAD(&obj->lut_list);
  73         spin_lock_init(&obj->lut_lock);
  74
  75         spin_lock_init(&obj->mmo.lock);
  76         obj->mmo.offsets = RB_ROOT;
  77
  78         init_rcu_head(&obj->rcu);
  79
  80         obj->ops = ops;
  81
  82         obj->mm.madv = I915_MADV_WILLNEED;
  83         INIT_RADIX_TREE(&obj->mm.get_page.radix, GFP_KERNEL | __GFP_NOWARN);
  84         mutex_init(&obj->mm.get_page.lock);
  85         INIT_RADIX_TREE(&obj->mm.get_dma_page.radix, GFP_KERNEL | __GFP_NOWARN);
  86         mutex_init(&obj->mm.get_dma_page.lock);
  87
  88         if (IS_ENABLED(CONFIG_LOCKDEP) && i915_gem_object_is_shrinkable(obj))
  89                 i915_gem_shrinker_taints_mutex(to_i915(obj->base.dev),
  90                                                &obj->mm.lock);
  91 }
  92
  93 /**
  94  * Mark up the object's coherency levels for a given cache_level
  95  * @obj: #drm_i915_gem_object
  96  * @cache_level: cache level
  97  */
  98 void i915_gem_object_set_cache_coherency(struct drm_i915_gem_object *obj,
  99                                          unsigned int cache_level)
 100 {
 101         obj->cache_level = cache_level;
 102
 103         if (cache_level != I915_CACHE_NONE)
 104                 obj->cache_coherent = (I915_BO_CACHE_COHERENT_FOR_READ |
 105                                        I915_BO_CACHE_COHERENT_FOR_WRITE);
 106         else if (HAS_LLC(to_i915(obj->base.dev)))
 107                 obj->cache_coherent = I915_BO_CACHE_COHERENT_FOR_READ;
 108         else
 109                 obj->cache_coherent = 0;
 110
 111         obj->cache_dirty =
 112                 !(obj->cache_coherent & I915_BO_CACHE_COHERENT_FOR_WRITE);
 113 }
 114
 115 static void i915_gem_close_object(struct drm_gem_object *gem, struct drm_file *file)
 116 {
 117         struct drm_i915_gem_object *obj = to_intel_bo(gem);
 118         struct drm_i915_file_private *fpriv = file->driver_priv;
 119         struct i915_lut_handle bookmark = {};
 120         struct i915_mmap_offset *mmo, *mn;
 121         struct i915_lut_handle *lut, *ln;
 122         LIST_HEAD(close);
 123
 124         spin_lock(&obj->lut_lock);
 125         list_for_each_entry_safe(lut, ln, &obj->lut_list, obj_link) {
 126                 struct i915_gem_context *ctx = lut->ctx;
 127
 128                 if (ctx && ctx->file_priv == fpriv) {
 129                         i915_gem_context_get(ctx);
 130                         list_move(&lut->obj_link, &close);
 131                 }
 132
 133                 /* Break long locks, and carefully continue on from this spot */
 134                 if (&ln->obj_link != &obj->lut_list) {
 135                         list_add_tail(&bookmark.obj_link, &ln->obj_link);
 136                         if (cond_resched_lock(&obj->lut_lock))
 137                                 list_safe_reset_next(&bookmark, ln, obj_link);
 138                         __list_del_entry(&bookmark.obj_link);
 139                 }
 140         }
 141         spin_unlock(&obj->lut_lock);
 142
 143         spin_lock(&obj->mmo.lock);
 144         rbtree_postorder_for_each_entry_safe(mmo, mn, &obj->mmo.offsets, offset)
 145                 drm_vma_node_revoke(&mmo->vma_node, file);
 146         spin_unlock(&obj->mmo.lock);
 147
 148         list_for_each_entry_safe(lut, ln, &close, obj_link) {
 149                 struct i915_gem_context *ctx = lut->ctx;
 150                 struct i915_vma *vma;
 151
 152                 /*
 153                  * We allow the process to have multiple handles to the same
 154                  * vma, in the same fd namespace, by virtue of flink/open.
 155                  */
 156
 157                 mutex_lock(&ctx->lut_mutex);
 158                 vma = radix_tree_delete(&ctx->handles_vma, lut->handle);
 159                 if (vma) {
 160                         GEM_BUG_ON(vma->obj != obj);
 161                         GEM_BUG_ON(!atomic_read(&vma->open_count));
 162                         i915_vma_close(vma);
 163                 }
 164                 mutex_unlock(&ctx->lut_mutex);
 165
 166                 i915_gem_context_put(lut->ctx);
 167                 i915_lut_handle_free(lut);
 168                 i915_gem_object_put(obj);
 169         }
 170 }
 171
 172 static void __i915_gem_free_object_rcu(struct rcu_head *head)
 173 {
 174         struct drm_i915_gem_object *obj =
 175                 container_of(head, typeof(*obj), rcu);
 176         struct drm_i915_private *i915 = to_i915(obj->base.dev);
 177
 178         dma_resv_fini(&obj->base._resv);
 179         i915_gem_object_free(obj);
 180
 181         GEM_BUG_ON(!atomic_read(&i915->mm.free_count));
 182         atomic_dec(&i915->mm.free_count);
 183 }
 184
 185 static void __i915_gem_object_free_mmaps(struct drm_i915_gem_object *obj)
 186 {
 187         /* Skip serialisation and waking the device if known to be not used. */
 188
 189         if (obj->userfault_count)
 190                 i915_gem_object_release_mmap_gtt(obj);
 191
 192         if (!RB_EMPTY_ROOT(&obj->mmo.offsets)) {
 193                 struct i915_mmap_offset *mmo, *mn;
 194
 195                 i915_gem_object_release_mmap_offset(obj);
 196
 197                 rbtree_postorder_for_each_entry_safe(mmo, mn,
 198                                                      &obj->mmo.offsets,
 199                                                      offset) {
 200                         drm_vma_offset_remove(obj->base.dev->vma_offset_manager,
 201                                               &mmo->vma_node);
 202                         kfree(mmo);
 203                 }
 204                 obj->mmo.offsets = RB_ROOT;
 205         }
 206 }
 207
 208 static void __i915_gem_free_objects(struct drm_i915_private *i915,
 209                                     struct llist_node *freed)
 210 {
 211         struct drm_i915_gem_object *obj, *on;
 212
 213         llist_for_each_entry_safe(obj, on, freed, freed) {
 214                 trace_i915_gem_object_destroy(obj);
 215
 216                 if (!list_empty(&obj->vma.list)) {
 217                         struct i915_vma *vma;
 218
 219                         /*
 220                          * Note that the vma keeps an object reference while
 221                          * it is active, so it *should* not sleep while we
 222                          * destroy it. Our debug code errs insits it *might*.
 223                          * For the moment, play along.
 224                          */
 225                         spin_lock(&obj->vma.lock);
 226                         while ((vma = list_first_entry_or_null(&obj->vma.list,
 227                                                                struct i915_vma,
 228                                                                obj_link))) {
 229                                 GEM_BUG_ON(vma->obj != obj);
 230                                 spin_unlock(&obj->vma.lock);
 231
 232                                 __i915_vma_put(vma);
 233
 234                                 spin_lock(&obj->vma.lock);
 235                         }
 236                         spin_unlock(&obj->vma.lock);
 237                 }
 238
 239                 __i915_gem_object_free_mmaps(obj);
 240
 241                 GEM_BUG_ON(!list_empty(&obj->lut_list));
 242
 243                 atomic_set(&obj->mm.pages_pin_count, 0);
 244                 __i915_gem_object_put_pages(obj);
 245                 GEM_BUG_ON(i915_gem_object_has_pages(obj));
 246                 bitmap_free(obj->bit_17);
 247
 248                 if (obj->base.import_attach)
 249                         drm_prime_gem_destroy(&obj->base, NULL);
 250
 251                 drm_gem_free_mmap_offset(&obj->base);
 252
 253                 if (obj->ops->release)
 254                         obj->ops->release(obj);
 255
 256                 /* But keep the pointer alive for RCU-protected lookups */
 257                 call_rcu(&obj->rcu, __i915_gem_free_object_rcu);
 258                 cond_resched();
 259         }
 260 }
 261
 262 void i915_gem_flush_free_objects(struct drm_i915_private *i915)
 263 {
 264         struct llist_node *freed = llist_del_all(&i915->mm.free_list);
 265
 266         if (unlikely(freed))
 267                 __i915_gem_free_objects(i915, freed);
 268 }
 269
 270 static void __i915_gem_free_work(struct work_struct *work)
 271 {
 272         struct drm_i915_private *i915 =
 273                 container_of(work, struct drm_i915_private, mm.free_work);
 274
 275         i915_gem_flush_free_objects(i915);
 276 }
 277
 278 static void i915_gem_free_object(struct drm_gem_object *gem_obj)
 279 {
 280         struct drm_i915_gem_object *obj = to_intel_bo(gem_obj);
 281         struct drm_i915_private *i915 = to_i915(obj->base.dev);
 282
 283         GEM_BUG_ON(i915_gem_object_is_framebuffer(obj));
 284
 285         /*
 286          * Before we free the object, make sure any pure RCU-only
 287          * read-side critical sections are complete, e.g.
 288          * i915_gem_busy_ioctl(). For the corresponding synchronized
 289          * lookup see i915_gem_object_lookup_rcu().
 290          */
 291         atomic_inc(&i915->mm.free_count);
 292
 293         /*
 294          * This serializes freeing with the shrinker. Since the free
 295          * is delayed, first by RCU then by the workqueue, we want the
 296          * shrinker to be able to free pages of unreferenced objects,
 297          * or else we may oom whilst there are plenty of deferred
 298          * freed objects.
 299          */
 300         i915_gem_object_make_unshrinkable(obj);
 301
 302         /*
 303          * Since we require blocking on struct_mutex to unbind the freed
 304          * object from the GPU before releasing resources back to the
 305          * system, we can not do that directly from the RCU callback (which may
 306          * be a softirq context), but must instead then defer that work onto a
 307          * kthread. We use the RCU callback rather than move the freed object
 308          * directly onto the work queue so that we can mix between using the
 309          * worker and performing frees directly from subsequent allocations for
 310          * crude but effective memory throttling.
 311          */
 312         if (llist_add(&obj->freed, &i915->mm.free_list))
 313                 queue_work(i915->wq, &i915->mm.free_work);
 314 }
 315
 316 static bool gpu_write_needs_clflush(struct drm_i915_gem_object *obj)
 317 {
 318         return !(obj->cache_level == I915_CACHE_NONE ||
 319                  obj->cache_level == I915_CACHE_WT);
 320 }
 321
 322 void
 323 i915_gem_object_flush_write_domain(struct drm_i915_gem_object *obj,
 324                                    unsigned int flush_domains)
 325 {
 326         struct i915_vma *vma;
 327
 328         assert_object_held(obj);
 329
 330         if (!(obj->write_domain & flush_domains))
 331                 return;
 332
 333         switch (obj->write_domain) {
 334         case I915_GEM_DOMAIN_GTT:
 335                 spin_lock(&obj->vma.lock);
 336                 for_each_ggtt_vma(vma, obj) {
 337                         if (i915_vma_unset_ggtt_write(vma))
 338                                 intel_gt_flush_ggtt_writes(vma->vm->gt);
 339                 }
 340                 spin_unlock(&obj->vma.lock);
 341
 342                 i915_gem_object_flush_frontbuffer(obj, ORIGIN_CPU);
 343                 break;
 344
 345         case I915_GEM_DOMAIN_WC:
 346                 wmb();
 347                 break;
 348
 349         case I915_GEM_DOMAIN_CPU:
 350                 i915_gem_clflush_object(obj, I915_CLFLUSH_SYNC);
 351                 break;
 352
 353         case I915_GEM_DOMAIN_RENDER:
 354                 if (gpu_write_needs_clflush(obj))
 355                         obj->cache_dirty = true;
 356                 break;
 357         }
 358
 359         obj->write_domain = 0;
 360 }
 361
 362 void __i915_gem_object_flush_frontbuffer(struct drm_i915_gem_object *obj,
 363                                          enum fb_op_origin origin)
 364 {
 365         struct intel_frontbuffer *front;
 366
 367         front = __intel_frontbuffer_get(obj);
 368         if (front) {
 369                 intel_frontbuffer_flush(front, origin);
 370                 intel_frontbuffer_put(front);
 371         }
 372 }
 373
 374 void __i915_gem_object_invalidate_frontbuffer(struct drm_i915_gem_object *obj,
 375                                               enum fb_op_origin origin)
 376 {
 377         struct intel_frontbuffer *front;
 378
 379         front = __intel_frontbuffer_get(obj);
 380         if (front) {
 381                 intel_frontbuffer_invalidate(front, origin);
 382                 intel_frontbuffer_put(front);
 383         }
 384 }
 385
 386 void i915_gem_init__objects(struct drm_i915_private *i915)
 387 {
 388         INIT_WORK(&i915->mm.free_work, __i915_gem_free_work);
 389 }
 390
 391 static void i915_global_objects_shrink(void)
 392 {
 393         kmem_cache_shrink(global.slab_objects);
 394 }
 395
 396 static void i915_global_objects_exit(void)
 397 {
 398         kmem_cache_destroy(global.slab_objects);
 399 }
 400
 401 static struct i915_global_object global = { {
 402         .shrink = i915_global_objects_shrink,
 403         .exit = i915_global_objects_exit,
 404 } };
 405
 406 int __init i915_global_objects_init(void)
 407 {
 408         global.slab_objects =
 409                 KMEM_CACHE(drm_i915_gem_object, SLAB_HWCACHE_ALIGN);
 410         if (!global.slab_objects)
 411                 return -ENOMEM;
 412
 413         i915_global_register(&global.base);
 414         return 0;
 415 }
 416
 417 static const struct drm_gem_object_funcs i915_gem_object_funcs = {
 418         .free = i915_gem_free_object,
 419         .close = i915_gem_close_object,
 420         .export = i915_gem_prime_export,
 421 };
 422
 423 #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
 424 #include "selftests/huge_gem_object.c"
 425 #include "selftests/huge_pages.c"
 426 #include "selftests/i915_gem_object.c"
 427 #include "selftests/i915_gem_coherency.c"
 428 #endif