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 "i915_drv.h"
  29 #include "i915_gem_clflush.h"
  30 #include "i915_gem_context.h"
  31 #include "i915_gem_mman.h"
  32 #include "i915_gem_object.h"
  33 #include "i915_globals.h"
  34 #include "i915_memcpy.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, unsigned flags)
  64 {
  65         /*
  66          * A gem object is embedded both in a struct ttm_buffer_object :/ and
  67          * in a drm_i915_gem_object. Make sure they are aliased.
  68          */
  69         BUILD_BUG_ON(offsetof(typeof(*obj), base) !=
  70                      offsetof(typeof(*obj), __do_not_access.base));
  71
  72         spin_lock_init(&obj->vma.lock);
  73         INIT_LIST_HEAD(&obj->vma.list);
  74
  75         INIT_LIST_HEAD(&obj->mm.link);
  76
  77         INIT_LIST_HEAD(&obj->lut_list);
  78         spin_lock_init(&obj->lut_lock);
  79
  80         spin_lock_init(&obj->mmo.lock);
  81         obj->mmo.offsets = RB_ROOT;
  82
  83         init_rcu_head(&obj->rcu);
  84
  85         obj->ops = ops;
  86         GEM_BUG_ON(flags & ~I915_BO_ALLOC_FLAGS);
  87         obj->flags = flags;
  88
  89         obj->mm.madv = I915_MADV_WILLNEED;
  90         INIT_RADIX_TREE(&obj->mm.get_page.radix, GFP_KERNEL | __GFP_NOWARN);
  91         mutex_init(&obj->mm.get_page.lock);
  92         INIT_RADIX_TREE(&obj->mm.get_dma_page.radix, GFP_KERNEL | __GFP_NOWARN);
  93         mutex_init(&obj->mm.get_dma_page.lock);
  94 }
  95
  96 /**
  97  * Mark up the object's coherency levels for a given cache_level
  98  * @obj: #drm_i915_gem_object
  99  * @cache_level: cache level
 100  */
 101 void i915_gem_object_set_cache_coherency(struct drm_i915_gem_object *obj,
 102                                          unsigned int cache_level)
 103 {
 104         obj->cache_level = cache_level;
 105
 106         if (cache_level != I915_CACHE_NONE)
 107                 obj->cache_coherent = (I915_BO_CACHE_COHERENT_FOR_READ |
 108                                        I915_BO_CACHE_COHERENT_FOR_WRITE);
 109         else if (HAS_LLC(to_i915(obj->base.dev)))
 110                 obj->cache_coherent = I915_BO_CACHE_COHERENT_FOR_READ;
 111         else
 112                 obj->cache_coherent = 0;
 113
 114         obj->cache_dirty =
 115                 !(obj->cache_coherent & I915_BO_CACHE_COHERENT_FOR_WRITE);
 116 }
 117
 118 static void i915_gem_close_object(struct drm_gem_object *gem, struct drm_file *file)
 119 {
 120         struct drm_i915_gem_object *obj = to_intel_bo(gem);
 121         struct drm_i915_file_private *fpriv = file->driver_priv;
 122         struct i915_lut_handle bookmark = {};
 123         struct i915_mmap_offset *mmo, *mn;
 124         struct i915_lut_handle *lut, *ln;
 125         LIST_HEAD(close);
 126
 127         spin_lock(&obj->lut_lock);
 128         list_for_each_entry_safe(lut, ln, &obj->lut_list, obj_link) {
 129                 struct i915_gem_context *ctx = lut->ctx;
 130
 131                 if (ctx && ctx->file_priv == fpriv) {
 132                         i915_gem_context_get(ctx);
 133                         list_move(&lut->obj_link, &close);
 134                 }
 135
 136                 /* Break long locks, and carefully continue on from this spot */
 137                 if (&ln->obj_link != &obj->lut_list) {
 138                         list_add_tail(&bookmark.obj_link, &ln->obj_link);
 139                         if (cond_resched_lock(&obj->lut_lock))
 140                                 list_safe_reset_next(&bookmark, ln, obj_link);
 141                         __list_del_entry(&bookmark.obj_link);
 142                 }
 143         }
 144         spin_unlock(&obj->lut_lock);
 145
 146         spin_lock(&obj->mmo.lock);
 147         rbtree_postorder_for_each_entry_safe(mmo, mn, &obj->mmo.offsets, offset)
 148                 drm_vma_node_revoke(&mmo->vma_node, file);
 149         spin_unlock(&obj->mmo.lock);
 150
 151         list_for_each_entry_safe(lut, ln, &close, obj_link) {
 152                 struct i915_gem_context *ctx = lut->ctx;
 153                 struct i915_vma *vma;
 154
 155                 /*
 156                  * We allow the process to have multiple handles to the same
 157                  * vma, in the same fd namespace, by virtue of flink/open.
 158                  */
 159
 160                 mutex_lock(&ctx->lut_mutex);
 161                 vma = radix_tree_delete(&ctx->handles_vma, lut->handle);
 162                 if (vma) {
 163                         GEM_BUG_ON(vma->obj != obj);
 164                         GEM_BUG_ON(!atomic_read(&vma->open_count));
 165                         i915_vma_close(vma);
 166                 }
 167                 mutex_unlock(&ctx->lut_mutex);
 168
 169                 i915_gem_context_put(lut->ctx);
 170                 i915_lut_handle_free(lut);
 171                 i915_gem_object_put(obj);
 172         }
 173 }
 174
 175 static void __i915_gem_free_object_rcu(struct rcu_head *head)
 176 {
 177         struct drm_i915_gem_object *obj =
 178                 container_of(head, typeof(*obj), rcu);
 179         struct drm_i915_private *i915 = to_i915(obj->base.dev);
 180
 181         dma_resv_fini(&obj->base._resv);
 182         i915_gem_object_free(obj);
 183
 184         GEM_BUG_ON(!atomic_read(&i915->mm.free_count));
 185         atomic_dec(&i915->mm.free_count);
 186 }
 187
 188 static void __i915_gem_object_free_mmaps(struct drm_i915_gem_object *obj)
 189 {
 190         /* Skip serialisation and waking the device if known to be not used. */
 191
 192         if (obj->userfault_count)
 193                 i915_gem_object_release_mmap_gtt(obj);
 194
 195         if (!RB_EMPTY_ROOT(&obj->mmo.offsets)) {
 196                 struct i915_mmap_offset *mmo, *mn;
 197
 198                 i915_gem_object_release_mmap_offset(obj);
 199
 200                 rbtree_postorder_for_each_entry_safe(mmo, mn,
 201                                                      &obj->mmo.offsets,
 202                                                      offset) {
 203                         drm_vma_offset_remove(obj->base.dev->vma_offset_manager,
 204                                               &mmo->vma_node);
 205                         kfree(mmo);
 206                 }
 207                 obj->mmo.offsets = RB_ROOT;
 208         }
 209 }
 210
 211 static void __i915_gem_free_objects(struct drm_i915_private *i915,
 212                                     struct llist_node *freed)
 213 {
 214         struct drm_i915_gem_object *obj, *on;
 215
 216         llist_for_each_entry_safe(obj, on, freed, freed) {
 217                 trace_i915_gem_object_destroy(obj);
 218
 219                 if (!list_empty(&obj->vma.list)) {
 220                         struct i915_vma *vma;
 221
 222                         /*
 223                          * Note that the vma keeps an object reference while
 224                          * it is active, so it *should* not sleep while we
 225                          * destroy it. Our debug code errs insits it *might*.
 226                          * For the moment, play along.
 227                          */
 228                         spin_lock(&obj->vma.lock);
 229                         while ((vma = list_first_entry_or_null(&obj->vma.list,
 230                                                                struct i915_vma,
 231                                                                obj_link))) {
 232                                 GEM_BUG_ON(vma->obj != obj);
 233                                 spin_unlock(&obj->vma.lock);
 234
 235                                 __i915_vma_put(vma);
 236
 237                                 spin_lock(&obj->vma.lock);
 238                         }
 239                         spin_unlock(&obj->vma.lock);
 240                 }
 241
 242                 __i915_gem_object_free_mmaps(obj);
 243
 244                 GEM_BUG_ON(!list_empty(&obj->lut_list));
 245
 246                 atomic_set(&obj->mm.pages_pin_count, 0);
 247                 __i915_gem_object_put_pages(obj);
 248                 GEM_BUG_ON(i915_gem_object_has_pages(obj));
 249                 bitmap_free(obj->bit_17);
 250
 251                 if (obj->base.import_attach)
 252                         drm_prime_gem_destroy(&obj->base, NULL);
 253
 254                 drm_gem_free_mmap_offset(&obj->base);
 255
 256                 if (obj->ops->release)
 257                         obj->ops->release(obj);
 258
 259                 if (obj->mm.n_placements > 1)
 260                         kfree(obj->mm.placements);
 261
 262                 if (obj->shares_resv_from)
 263                         i915_vm_resv_put(obj->shares_resv_from);
 264
 265                 /* But keep the pointer alive for RCU-protected lookups */
 266                 call_rcu(&obj->rcu, __i915_gem_free_object_rcu);
 267                 cond_resched();
 268         }
 269 }
 270
 271 void i915_gem_flush_free_objects(struct drm_i915_private *i915)
 272 {
 273         struct llist_node *freed = llist_del_all(&i915->mm.free_list);
 274
 275         if (unlikely(freed))
 276                 __i915_gem_free_objects(i915, freed);
 277 }
 278
 279 static void __i915_gem_free_work(struct work_struct *work)
 280 {
 281         struct drm_i915_private *i915 =
 282                 container_of(work, struct drm_i915_private, mm.free_work);
 283
 284         i915_gem_flush_free_objects(i915);
 285 }
 286
 287 static void i915_gem_free_object(struct drm_gem_object *gem_obj)
 288 {
 289         struct drm_i915_gem_object *obj = to_intel_bo(gem_obj);
 290         struct drm_i915_private *i915 = to_i915(obj->base.dev);
 291
 292         GEM_BUG_ON(i915_gem_object_is_framebuffer(obj));
 293
 294         /*
 295          * Before we free the object, make sure any pure RCU-only
 296          * read-side critical sections are complete, e.g.
 297          * i915_gem_busy_ioctl(). For the corresponding synchronized
 298          * lookup see i915_gem_object_lookup_rcu().
 299          */
 300         atomic_inc(&i915->mm.free_count);
 301
 302         /*
 303          * This serializes freeing with the shrinker. Since the free
 304          * is delayed, first by RCU then by the workqueue, we want the
 305          * shrinker to be able to free pages of unreferenced objects,
 306          * or else we may oom whilst there are plenty of deferred
 307          * freed objects.
 308          */
 309         i915_gem_object_make_unshrinkable(obj);
 310
 311         /*
 312          * Since we require blocking on struct_mutex to unbind the freed
 313          * object from the GPU before releasing resources back to the
 314          * system, we can not do that directly from the RCU callback (which may
 315          * be a softirq context), but must instead then defer that work onto a
 316          * kthread. We use the RCU callback rather than move the freed object
 317          * directly onto the work queue so that we can mix between using the
 318          * worker and performing frees directly from subsequent allocations for
 319          * crude but effective memory throttling.
 320          */
 321         if (llist_add(&obj->freed, &i915->mm.free_list))
 322                 queue_work(i915->wq, &i915->mm.free_work);
 323 }
 324
 325 void __i915_gem_object_flush_frontbuffer(struct drm_i915_gem_object *obj,
 326                                          enum fb_op_origin origin)
 327 {
 328         struct intel_frontbuffer *front;
 329
 330         front = __intel_frontbuffer_get(obj);
 331         if (front) {
 332                 intel_frontbuffer_flush(front, origin);
 333                 intel_frontbuffer_put(front);
 334         }
 335 }
 336
 337 void __i915_gem_object_invalidate_frontbuffer(struct drm_i915_gem_object *obj,
 338                                               enum fb_op_origin origin)
 339 {
 340         struct intel_frontbuffer *front;
 341
 342         front = __intel_frontbuffer_get(obj);
 343         if (front) {
 344                 intel_frontbuffer_invalidate(front, origin);
 345                 intel_frontbuffer_put(front);
 346         }
 347 }
 348
 349 static void
 350 i915_gem_object_read_from_page_kmap(struct drm_i915_gem_object *obj, u64 offset, void *dst, int size)
 351 {
 352         void *src_map;
 353         void *src_ptr;
 354
 355         src_map = kmap_atomic(i915_gem_object_get_page(obj, offset >> PAGE_SHIFT));
 356
 357         src_ptr = src_map + offset_in_page(offset);
 358         if (!(obj->cache_coherent & I915_BO_CACHE_COHERENT_FOR_READ))
 359                 drm_clflush_virt_range(src_ptr, size);
 360         memcpy(dst, src_ptr, size);
 361
 362         kunmap_atomic(src_map);
 363 }
 364
 365 static void
 366 i915_gem_object_read_from_page_iomap(struct drm_i915_gem_object *obj, u64 offset, void *dst, int size)
 367 {
 368         void __iomem *src_map;
 369         void __iomem *src_ptr;
 370         dma_addr_t dma = i915_gem_object_get_dma_address(obj, offset >> PAGE_SHIFT);
 371
 372         src_map = io_mapping_map_wc(&obj->mm.region->iomap,
 373                                     dma - obj->mm.region->region.start,
 374                                     PAGE_SIZE);
 375
 376         src_ptr = src_map + offset_in_page(offset);
 377         if (!i915_memcpy_from_wc(dst, (void __force *)src_ptr, size))
 378                 memcpy_fromio(dst, src_ptr, size);
 379
 380         io_mapping_unmap(src_map);
 381 }
 382
 383 /**
 384  * i915_gem_object_read_from_page - read data from the page of a GEM object
 385  * @obj: GEM object to read from
 386  * @offset: offset within the object
 387  * @dst: buffer to store the read data
 388  * @size: size to read
 389  *
 390  * Reads data from @obj at the specified offset. The requested region to read
 391  * from can't cross a page boundary. The caller must ensure that @obj pages
 392  * are pinned and that @obj is synced wrt. any related writes.
 393  *
 394  * Returns 0 on success or -ENODEV if the type of @obj's backing store is
 395  * unsupported.
 396  */
 397 int i915_gem_object_read_from_page(struct drm_i915_gem_object *obj, u64 offset, void *dst, int size)
 398 {
 399         GEM_BUG_ON(offset >= obj->base.size);
 400         GEM_BUG_ON(offset_in_page(offset) > PAGE_SIZE - size);
 401         GEM_BUG_ON(!i915_gem_object_has_pinned_pages(obj));
 402
 403         if (i915_gem_object_has_struct_page(obj))
 404                 i915_gem_object_read_from_page_kmap(obj, offset, dst, size);
 405         else if (i915_gem_object_has_iomem(obj))
 406                 i915_gem_object_read_from_page_iomap(obj, offset, dst, size);
 407         else
 408                 return -ENODEV;
 409
 410         return 0;
 411 }
 412
 413 void i915_gem_init__objects(struct drm_i915_private *i915)
 414 {
 415         INIT_WORK(&i915->mm.free_work, __i915_gem_free_work);
 416 }
 417
 418 static void i915_global_objects_shrink(void)
 419 {
 420         kmem_cache_shrink(global.slab_objects);
 421 }
 422
 423 static void i915_global_objects_exit(void)
 424 {
 425         kmem_cache_destroy(global.slab_objects);
 426 }
 427
 428 static struct i915_global_object global = { {
 429         .shrink = i915_global_objects_shrink,
 430         .exit = i915_global_objects_exit,
 431 } };
 432
 433 int __init i915_global_objects_init(void)
 434 {
 435         global.slab_objects =
 436                 KMEM_CACHE(drm_i915_gem_object, SLAB_HWCACHE_ALIGN);
 437         if (!global.slab_objects)
 438                 return -ENOMEM;
 439
 440         i915_global_register(&global.base);
 441         return 0;
 442 }
 443
 444 static const struct drm_gem_object_funcs i915_gem_object_funcs = {
 445         .free = i915_gem_free_object,
 446         .close = i915_gem_close_object,
 447         .export = i915_gem_prime_export,
 448 };
 449
 450 #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
 451 #include "selftests/huge_gem_object.c"
 452 #include "selftests/huge_pages.c"
 453 #include "selftests/i915_gem_object.c"
 454 #include "selftests/i915_gem_coherency.c"
 455 #endif