drivers/gpu/drm/vc4/vc4_gem.c

   1 /*
   2  * Copyright © 2014 Broadcom
   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 #include <linux/module.h>
  25 #include <linux/platform_device.h>
  26 #include <linux/pm_runtime.h>
  27 #include <linux/device.h>
  28 #include <linux/io.h>
  29 #include <linux/sched/signal.h>
  30
  31 #include "uapi/drm/vc4_drm.h"
  32 #include "vc4_drv.h"
  33 #include "vc4_regs.h"
  34 #include "vc4_trace.h"
  35
  36 static void
  37 vc4_queue_hangcheck(struct drm_device *dev)
  38 {
  39         struct vc4_dev *vc4 = to_vc4_dev(dev);
  40
  41         mod_timer(&vc4->hangcheck.timer,
  42                   round_jiffies_up(jiffies + msecs_to_jiffies(100)));
  43 }
  44
  45 struct vc4_hang_state {
  46         struct drm_vc4_get_hang_state user_state;
  47
  48         u32 bo_count;
  49         struct drm_gem_object **bo;
  50 };
  51
  52 static void
  53 vc4_free_hang_state(struct drm_device *dev, struct vc4_hang_state *state)
  54 {
  55         unsigned int i;
  56
  57         for (i = 0; i < state->user_state.bo_count; i++)
  58                 drm_gem_object_put_unlocked(state->bo[i]);
  59
  60         kfree(state);
  61 }
  62
  63 int
  64 vc4_get_hang_state_ioctl(struct drm_device *dev, void *data,
  65                          struct drm_file *file_priv)
  66 {
  67         struct drm_vc4_get_hang_state *get_state = data;
  68         struct drm_vc4_get_hang_state_bo *bo_state;
  69         struct vc4_hang_state *kernel_state;
  70         struct drm_vc4_get_hang_state *state;
  71         struct vc4_dev *vc4 = to_vc4_dev(dev);
  72         unsigned long irqflags;
  73         u32 i;
  74         int ret = 0;
  75
  76         spin_lock_irqsave(&vc4->job_lock, irqflags);
  77         kernel_state = vc4->hang_state;
  78         if (!kernel_state) {
  79                 spin_unlock_irqrestore(&vc4->job_lock, irqflags);
  80                 return -ENOENT;
  81         }
  82         state = &kernel_state->user_state;
  83
  84         /* If the user's array isn't big enough, just return the
  85          * required array size.
  86          */
  87         if (get_state->bo_count < state->bo_count) {
  88                 get_state->bo_count = state->bo_count;
  89                 spin_unlock_irqrestore(&vc4->job_lock, irqflags);
  90                 return 0;
  91         }
  92
  93         vc4->hang_state = NULL;
  94         spin_unlock_irqrestore(&vc4->job_lock, irqflags);
  95
  96         /* Save the user's BO pointer, so we don't stomp it with the memcpy. */
  97         state->bo = get_state->bo;
  98         memcpy(get_state, state, sizeof(*state));
  99
 100         bo_state = kcalloc(state->bo_count, sizeof(*bo_state), GFP_KERNEL);
 101         if (!bo_state) {
 102                 ret = -ENOMEM;
 103                 goto err_free;
 104         }
 105
 106         for (i = 0; i < state->bo_count; i++) {
 107                 struct vc4_bo *vc4_bo = to_vc4_bo(kernel_state->bo[i]);
 108                 u32 handle;
 109
 110                 ret = drm_gem_handle_create(file_priv, kernel_state->bo[i],
 111                                             &handle);
 112
 113                 if (ret) {
 114                         state->bo_count = i;
 115                         goto err_delete_handle;
 116                 }
 117                 bo_state[i].handle = handle;
 118                 bo_state[i].paddr = vc4_bo->base.paddr;
 119                 bo_state[i].size = vc4_bo->base.base.size;
 120         }
 121
 122         if (copy_to_user(u64_to_user_ptr(get_state->bo),
 123                          bo_state,
 124                          state->bo_count * sizeof(*bo_state)))
 125                 ret = -EFAULT;
 126
 127 err_delete_handle:
 128         if (ret) {
 129                 for (i = 0; i < state->bo_count; i++)
 130                         drm_gem_handle_delete(file_priv, bo_state[i].handle);
 131         }
 132
 133 err_free:
 134         vc4_free_hang_state(dev, kernel_state);
 135         kfree(bo_state);
 136
 137         return ret;
 138 }
 139
 140 static void
 141 vc4_save_hang_state(struct drm_device *dev)
 142 {
 143         struct vc4_dev *vc4 = to_vc4_dev(dev);
 144         struct drm_vc4_get_hang_state *state;
 145         struct vc4_hang_state *kernel_state;
 146         struct vc4_exec_info *exec[2];
 147         struct vc4_bo *bo;
 148         unsigned long irqflags;
 149         unsigned int i, j, k, unref_list_count;
 150
 151         kernel_state = kcalloc(1, sizeof(*kernel_state), GFP_KERNEL);
 152         if (!kernel_state)
 153                 return;
 154
 155         state = &kernel_state->user_state;
 156
 157         spin_lock_irqsave(&vc4->job_lock, irqflags);
 158         exec[0] = vc4_first_bin_job(vc4);
 159         exec[1] = vc4_first_render_job(vc4);
 160         if (!exec[0] && !exec[1]) {
 161                 spin_unlock_irqrestore(&vc4->job_lock, irqflags);
 162                 return;
 163         }
 164
 165         /* Get the bos from both binner and renderer into hang state. */
 166         state->bo_count = 0;
 167         for (i = 0; i < 2; i++) {
 168                 if (!exec[i])
 169                         continue;
 170
 171                 unref_list_count = 0;
 172                 list_for_each_entry(bo, &exec[i]->unref_list, unref_head)
 173                         unref_list_count++;
 174                 state->bo_count += exec[i]->bo_count + unref_list_count;
 175         }
 176
 177         kernel_state->bo = kcalloc(state->bo_count,
 178                                    sizeof(*kernel_state->bo), GFP_ATOMIC);
 179
 180         if (!kernel_state->bo) {
 181                 spin_unlock_irqrestore(&vc4->job_lock, irqflags);
 182                 return;
 183         }
 184
 185         k = 0;
 186         for (i = 0; i < 2; i++) {
 187                 if (!exec[i])
 188                         continue;
 189
 190                 for (j = 0; j < exec[i]->bo_count; j++) {
 191                         bo = to_vc4_bo(&exec[i]->bo[j]->base);
 192
 193                         /* Retain BOs just in case they were marked purgeable.
 194                          * This prevents the BO from being purged before
 195                          * someone had a chance to dump the hang state.
 196                          */
 197                         WARN_ON(!refcount_read(&bo->usecnt));
 198                         refcount_inc(&bo->usecnt);
 199                         drm_gem_object_get(&exec[i]->bo[j]->base);
 200                         kernel_state->bo[k++] = &exec[i]->bo[j]->base;
 201                 }
 202
 203                 list_for_each_entry(bo, &exec[i]->unref_list, unref_head) {
 204                         /* No need to retain BOs coming from the ->unref_list
 205                          * because they are naturally unpurgeable.
 206                          */
 207                         drm_gem_object_get(&bo->base.base);
 208                         kernel_state->bo[k++] = &bo->base.base;
 209                 }
 210         }
 211
 212         WARN_ON_ONCE(k != state->bo_count);
 213
 214         if (exec[0])
 215                 state->start_bin = exec[0]->ct0ca;
 216         if (exec[1])
 217                 state->start_render = exec[1]->ct1ca;
 218
 219         spin_unlock_irqrestore(&vc4->job_lock, irqflags);
 220
 221         state->ct0ca = V3D_READ(V3D_CTNCA(0));
 222         state->ct0ea = V3D_READ(V3D_CTNEA(0));
 223
 224         state->ct1ca = V3D_READ(V3D_CTNCA(1));
 225         state->ct1ea = V3D_READ(V3D_CTNEA(1));
 226
 227         state->ct0cs = V3D_READ(V3D_CTNCS(0));
 228         state->ct1cs = V3D_READ(V3D_CTNCS(1));
 229
 230         state->ct0ra0 = V3D_READ(V3D_CT00RA0);
 231         state->ct1ra0 = V3D_READ(V3D_CT01RA0);
 232
 233         state->bpca = V3D_READ(V3D_BPCA);
 234         state->bpcs = V3D_READ(V3D_BPCS);
 235         state->bpoa = V3D_READ(V3D_BPOA);
 236         state->bpos = V3D_READ(V3D_BPOS);
 237
 238         state->vpmbase = V3D_READ(V3D_VPMBASE);
 239
 240         state->dbge = V3D_READ(V3D_DBGE);
 241         state->fdbgo = V3D_READ(V3D_FDBGO);
 242         state->fdbgb = V3D_READ(V3D_FDBGB);
 243         state->fdbgr = V3D_READ(V3D_FDBGR);
 244         state->fdbgs = V3D_READ(V3D_FDBGS);
 245         state->errstat = V3D_READ(V3D_ERRSTAT);
 246
 247         /* We need to turn purgeable BOs into unpurgeable ones so that
 248          * userspace has a chance to dump the hang state before the kernel
 249          * decides to purge those BOs.
 250          * Note that BO consistency at dump time cannot be guaranteed. For
 251          * example, if the owner of these BOs decides to re-use them or mark
 252          * them purgeable again there's nothing we can do to prevent it.
 253          */
 254         for (i = 0; i < kernel_state->user_state.bo_count; i++) {
 255                 struct vc4_bo *bo = to_vc4_bo(kernel_state->bo[i]);
 256
 257                 if (bo->madv == __VC4_MADV_NOTSUPP)
 258                         continue;
 259
 260                 mutex_lock(&bo->madv_lock);
 261                 if (!WARN_ON(bo->madv == __VC4_MADV_PURGED))
 262                         bo->madv = VC4_MADV_WILLNEED;
 263                 refcount_dec(&bo->usecnt);
 264                 mutex_unlock(&bo->madv_lock);
 265         }
 266
 267         spin_lock_irqsave(&vc4->job_lock, irqflags);
 268         if (vc4->hang_state) {
 269                 spin_unlock_irqrestore(&vc4->job_lock, irqflags);
 270                 vc4_free_hang_state(dev, kernel_state);
 271         } else {
 272                 vc4->hang_state = kernel_state;
 273                 spin_unlock_irqrestore(&vc4->job_lock, irqflags);
 274         }
 275 }
 276
 277 static void
 278 vc4_reset(struct drm_device *dev)
 279 {
 280         struct vc4_dev *vc4 = to_vc4_dev(dev);
 281
 282         DRM_INFO("Resetting GPU.\n");
 283
 284         mutex_lock(&vc4->power_lock);
 285         if (vc4->power_refcount) {
 286                 /* Power the device off and back on the by dropping the
 287                  * reference on runtime PM.
 288                  */
 289                 pm_runtime_put_sync_suspend(&vc4->v3d->pdev->dev);
 290                 pm_runtime_get_sync(&vc4->v3d->pdev->dev);
 291         }
 292         mutex_unlock(&vc4->power_lock);
 293
 294         vc4_irq_reset(dev);
 295
 296         /* Rearm the hangcheck -- another job might have been waiting
 297          * for our hung one to get kicked off, and vc4_irq_reset()
 298          * would have started it.
 299          */
 300         vc4_queue_hangcheck(dev);
 301 }
 302
 303 static void
 304 vc4_reset_work(struct work_struct *work)
 305 {
 306         struct vc4_dev *vc4 =
 307                 container_of(work, struct vc4_dev, hangcheck.reset_work);
 308
 309         vc4_save_hang_state(vc4->dev);
 310
 311         vc4_reset(vc4->dev);
 312 }
 313
 314 static void
 315 vc4_hangcheck_elapsed(struct timer_list *t)
 316 {
 317         struct vc4_dev *vc4 = from_timer(vc4, t, hangcheck.timer);
 318         struct drm_device *dev = vc4->dev;
 319         uint32_t ct0ca, ct1ca;
 320         unsigned long irqflags;
 321         struct vc4_exec_info *bin_exec, *render_exec;
 322
 323         spin_lock_irqsave(&vc4->job_lock, irqflags);
 324
 325         bin_exec = vc4_first_bin_job(vc4);
 326         render_exec = vc4_first_render_job(vc4);
 327
 328         /* If idle, we can stop watching for hangs. */
 329         if (!bin_exec && !render_exec) {
 330                 spin_unlock_irqrestore(&vc4->job_lock, irqflags);
 331                 return;
 332         }
 333
 334         ct0ca = V3D_READ(V3D_CTNCA(0));
 335         ct1ca = V3D_READ(V3D_CTNCA(1));
 336
 337         /* If we've made any progress in execution, rearm the timer
 338          * and wait.
 339          */
 340         if ((bin_exec && ct0ca != bin_exec->last_ct0ca) ||
 341             (render_exec && ct1ca != render_exec->last_ct1ca)) {
 342                 if (bin_exec)
 343                         bin_exec->last_ct0ca = ct0ca;
 344                 if (render_exec)
 345                         render_exec->last_ct1ca = ct1ca;
 346                 spin_unlock_irqrestore(&vc4->job_lock, irqflags);
 347                 vc4_queue_hangcheck(dev);
 348                 return;
 349         }
 350
 351         spin_unlock_irqrestore(&vc4->job_lock, irqflags);
 352
 353         /* We've gone too long with no progress, reset.  This has to
 354          * be done from a work struct, since resetting can sleep and
 355          * this timer hook isn't allowed to.
 356          */
 357         schedule_work(&vc4->hangcheck.reset_work);
 358 }
 359
 360 static void
 361 submit_cl(struct drm_device *dev, uint32_t thread, uint32_t start, uint32_t end)
 362 {
 363         struct vc4_dev *vc4 = to_vc4_dev(dev);
 364
 365         /* Set the current and end address of the control list.
 366          * Writing the end register is what starts the job.
 367          */
 368         V3D_WRITE(V3D_CTNCA(thread), start);
 369         V3D_WRITE(V3D_CTNEA(thread), end);
 370 }
 371
 372 int
 373 vc4_wait_for_seqno(struct drm_device *dev, uint64_t seqno, uint64_t timeout_ns,
 374                    bool interruptible)
 375 {
 376         struct vc4_dev *vc4 = to_vc4_dev(dev);
 377         int ret = 0;
 378         unsigned long timeout_expire;
 379         DEFINE_WAIT(wait);
 380
 381         if (vc4->finished_seqno >= seqno)
 382                 return 0;
 383
 384         if (timeout_ns == 0)
 385                 return -ETIME;
 386
 387         timeout_expire = jiffies + nsecs_to_jiffies(timeout_ns);
 388
 389         trace_vc4_wait_for_seqno_begin(dev, seqno, timeout_ns);
 390         for (;;) {
 391                 prepare_to_wait(&vc4->job_wait_queue, &wait,
 392                                 interruptible ? TASK_INTERRUPTIBLE :
 393                                 TASK_UNINTERRUPTIBLE);
 394
 395                 if (interruptible && signal_pending(current)) {
 396                         ret = -ERESTARTSYS;
 397                         break;
 398                 }
 399
 400                 if (vc4->finished_seqno >= seqno)
 401                         break;
 402
 403                 if (timeout_ns != ~0ull) {
 404                         if (time_after_eq(jiffies, timeout_expire)) {
 405                                 ret = -ETIME;
 406                                 break;
 407                         }
 408                         schedule_timeout(timeout_expire - jiffies);
 409                 } else {
 410                         schedule();
 411                 }
 412         }
 413
 414         finish_wait(&vc4->job_wait_queue, &wait);
 415         trace_vc4_wait_for_seqno_end(dev, seqno);
 416
 417         return ret;
 418 }
 419
 420 static void
 421 vc4_flush_caches(struct drm_device *dev)
 422 {
 423         struct vc4_dev *vc4 = to_vc4_dev(dev);
 424
 425         /* Flush the GPU L2 caches.  These caches sit on top of system
 426          * L3 (the 128kb or so shared with the CPU), and are
 427          * non-allocating in the L3.
 428          */
 429         V3D_WRITE(V3D_L2CACTL,
 430                   V3D_L2CACTL_L2CCLR);
 431
 432         V3D_WRITE(V3D_SLCACTL,
 433                   VC4_SET_FIELD(0xf, V3D_SLCACTL_T1CC) |
 434                   VC4_SET_FIELD(0xf, V3D_SLCACTL_T0CC) |
 435                   VC4_SET_FIELD(0xf, V3D_SLCACTL_UCC) |
 436                   VC4_SET_FIELD(0xf, V3D_SLCACTL_ICC));
 437 }
 438
 439 static void
 440 vc4_flush_texture_caches(struct drm_device *dev)
 441 {
 442         struct vc4_dev *vc4 = to_vc4_dev(dev);
 443
 444         V3D_WRITE(V3D_L2CACTL,
 445                   V3D_L2CACTL_L2CCLR);
 446
 447         V3D_WRITE(V3D_SLCACTL,
 448                   VC4_SET_FIELD(0xf, V3D_SLCACTL_T1CC) |
 449                   VC4_SET_FIELD(0xf, V3D_SLCACTL_T0CC));
 450 }
 451
 452 /* Sets the registers for the next job to be actually be executed in
 453  * the hardware.
 454  *
 455  * The job_lock should be held during this.
 456  */
 457 void
 458 vc4_submit_next_bin_job(struct drm_device *dev)
 459 {
 460         struct vc4_dev *vc4 = to_vc4_dev(dev);
 461         struct vc4_exec_info *exec;
 462
 463 again:
 464         exec = vc4_first_bin_job(vc4);
 465         if (!exec)
 466                 return;
 467
 468         vc4_flush_caches(dev);
 469
 470         /* Only start the perfmon if it was not already started by a previous
 471          * job.
 472          */
 473         if (exec->perfmon && vc4->active_perfmon != exec->perfmon)
 474                 vc4_perfmon_start(vc4, exec->perfmon);
 475
 476         /* Either put the job in the binner if it uses the binner, or
 477          * immediately move it to the to-be-rendered queue.
 478          */
 479         if (exec->ct0ca != exec->ct0ea) {
 480                 submit_cl(dev, 0, exec->ct0ca, exec->ct0ea);
 481         } else {
 482                 struct vc4_exec_info *next;
 483
 484                 vc4_move_job_to_render(dev, exec);
 485                 next = vc4_first_bin_job(vc4);
 486
 487                 /* We can't start the next bin job if the previous job had a
 488                  * different perfmon instance attached to it. The same goes
 489                  * if one of them had a perfmon attached to it and the other
 490                  * one doesn't.
 491                  */
 492                 if (next && next->perfmon == exec->perfmon)
 493                         goto again;
 494         }
 495 }
 496
 497 void
 498 vc4_submit_next_render_job(struct drm_device *dev)
 499 {
 500         struct vc4_dev *vc4 = to_vc4_dev(dev);
 501         struct vc4_exec_info *exec = vc4_first_render_job(vc4);
 502
 503         if (!exec)
 504                 return;
 505
 506         /* A previous RCL may have written to one of our textures, and
 507          * our full cache flush at bin time may have occurred before
 508          * that RCL completed.  Flush the texture cache now, but not
 509          * the instructions or uniforms (since we don't write those
 510          * from an RCL).
 511          */
 512         vc4_flush_texture_caches(dev);
 513
 514         submit_cl(dev, 1, exec->ct1ca, exec->ct1ea);
 515 }
 516
 517 void
 518 vc4_move_job_to_render(struct drm_device *dev, struct vc4_exec_info *exec)
 519 {
 520         struct vc4_dev *vc4 = to_vc4_dev(dev);
 521         bool was_empty = list_empty(&vc4->render_job_list);
 522
 523         list_move_tail(&exec->head, &vc4->render_job_list);
 524         if (was_empty)
 525                 vc4_submit_next_render_job(dev);
 526 }
 527
 528 static void
 529 vc4_update_bo_seqnos(struct vc4_exec_info *exec, uint64_t seqno)
 530 {
 531         struct vc4_bo *bo;
 532         unsigned i;
 533
 534         for (i = 0; i < exec->bo_count; i++) {
 535                 bo = to_vc4_bo(&exec->bo[i]->base);
 536                 bo->seqno = seqno;
 537
 538                 reservation_object_add_shared_fence(bo->resv, exec->fence);
 539         }
 540
 541         list_for_each_entry(bo, &exec->unref_list, unref_head) {
 542                 bo->seqno = seqno;
 543         }
 544
 545         for (i = 0; i < exec->rcl_write_bo_count; i++) {
 546                 bo = to_vc4_bo(&exec->rcl_write_bo[i]->base);
 547                 bo->write_seqno = seqno;
 548
 549                 reservation_object_add_excl_fence(bo->resv, exec->fence);
 550         }
 551 }
 552
 553 static void
 554 vc4_unlock_bo_reservations(struct drm_device *dev,
 555                            struct vc4_exec_info *exec,
 556                            struct ww_acquire_ctx *acquire_ctx)
 557 {
 558         int i;
 559
 560         for (i = 0; i < exec->bo_count; i++) {
 561                 struct vc4_bo *bo = to_vc4_bo(&exec->bo[i]->base);
 562
 563                 ww_mutex_unlock(&bo->resv->lock);
 564         }
 565
 566         ww_acquire_fini(acquire_ctx);
 567 }
 568
 569 /* Takes the reservation lock on all the BOs being referenced, so that
 570  * at queue submit time we can update the reservations.
 571  *
 572  * We don't lock the RCL the tile alloc/state BOs, or overflow memory
 573  * (all of which are on exec->unref_list).  They're entirely private
 574  * to vc4, so we don't attach dma-buf fences to them.
 575  */
 576 static int
 577 vc4_lock_bo_reservations(struct drm_device *dev,
 578                          struct vc4_exec_info *exec,
 579                          struct ww_acquire_ctx *acquire_ctx)
 580 {
 581         int contended_lock = -1;
 582         int i, ret;
 583         struct vc4_bo *bo;
 584
 585         ww_acquire_init(acquire_ctx, &reservation_ww_class);
 586
 587 retry:
 588         if (contended_lock != -1) {
 589                 bo = to_vc4_bo(&exec->bo[contended_lock]->base);
 590                 ret = ww_mutex_lock_slow_interruptible(&bo->resv->lock,
 591                                                        acquire_ctx);
 592                 if (ret) {
 593                         ww_acquire_done(acquire_ctx);
 594                         return ret;
 595                 }
 596         }
 597
 598         for (i = 0; i < exec->bo_count; i++) {
 599                 if (i == contended_lock)
 600                         continue;
 601
 602                 bo = to_vc4_bo(&exec->bo[i]->base);
 603
 604                 ret = ww_mutex_lock_interruptible(&bo->resv->lock, acquire_ctx);
 605                 if (ret) {
 606                         int j;
 607
 608                         for (j = 0; j < i; j++) {
 609                                 bo = to_vc4_bo(&exec->bo[j]->base);
 610                                 ww_mutex_unlock(&bo->resv->lock);
 611                         }
 612
 613                         if (contended_lock != -1 && contended_lock >= i) {
 614                                 bo = to_vc4_bo(&exec->bo[contended_lock]->base);
 615
 616                                 ww_mutex_unlock(&bo->resv->lock);
 617                         }
 618
 619                         if (ret == -EDEADLK) {
 620                                 contended_lock = i;
 621                                 goto retry;
 622                         }
 623
 624                         ww_acquire_done(acquire_ctx);
 625                         return ret;
 626                 }
 627         }
 628
 629         ww_acquire_done(acquire_ctx);
 630
 631         /* Reserve space for our shared (read-only) fence references,
 632          * before we commit the CL to the hardware.
 633          */
 634         for (i = 0; i < exec->bo_count; i++) {
 635                 bo = to_vc4_bo(&exec->bo[i]->base);
 636
 637                 ret = reservation_object_reserve_shared(bo->resv);
 638                 if (ret) {
 639                         vc4_unlock_bo_reservations(dev, exec, acquire_ctx);
 640                         return ret;
 641                 }
 642         }
 643
 644         return 0;
 645 }
 646
 647 /* Queues a struct vc4_exec_info for execution.  If no job is
 648  * currently executing, then submits it.
 649  *
 650  * Unlike most GPUs, our hardware only handles one command list at a
 651  * time.  To queue multiple jobs at once, we'd need to edit the
 652  * previous command list to have a jump to the new one at the end, and
 653  * then bump the end address.  That's a change for a later date,
 654  * though.
 655  */
 656 static int
 657 vc4_queue_submit(struct drm_device *dev, struct vc4_exec_info *exec,
 658                  struct ww_acquire_ctx *acquire_ctx)
 659 {
 660         struct vc4_dev *vc4 = to_vc4_dev(dev);
 661         struct vc4_exec_info *renderjob;
 662         uint64_t seqno;
 663         unsigned long irqflags;
 664         struct vc4_fence *fence;
 665
 666         fence = kzalloc(sizeof(*fence), GFP_KERNEL);
 667         if (!fence)
 668                 return -ENOMEM;
 669         fence->dev = dev;
 670
 671         spin_lock_irqsave(&vc4->job_lock, irqflags);
 672
 673         seqno = ++vc4->emit_seqno;
 674         exec->seqno = seqno;
 675
 676         dma_fence_init(&fence->base, &vc4_fence_ops, &vc4->job_lock,
 677                        vc4->dma_fence_context, exec->seqno);
 678         fence->seqno = exec->seqno;
 679         exec->fence = &fence->base;
 680
 681         vc4_update_bo_seqnos(exec, seqno);
 682
 683         vc4_unlock_bo_reservations(dev, exec, acquire_ctx);
 684
 685         list_add_tail(&exec->head, &vc4->bin_job_list);
 686
 687         /* If no bin job was executing and if the render job (if any) has the
 688          * same perfmon as our job attached to it (or if both jobs don't have
 689          * perfmon activated), then kick ours off.  Otherwise, it'll get
 690          * started when the previous job's flush/render done interrupt occurs.
 691          */
 692         renderjob = vc4_first_render_job(vc4);
 693         if (vc4_first_bin_job(vc4) == exec &&
 694             (!renderjob || renderjob->perfmon == exec->perfmon)) {
 695                 vc4_submit_next_bin_job(dev);
 696                 vc4_queue_hangcheck(dev);
 697         }
 698
 699         spin_unlock_irqrestore(&vc4->job_lock, irqflags);
 700
 701         return 0;
 702 }
 703
 704 /**
 705  * vc4_cl_lookup_bos() - Sets up exec->bo[] with the GEM objects
 706  * referenced by the job.
 707  * @dev: DRM device
 708  * @file_priv: DRM file for this fd
 709  * @exec: V3D job being set up
 710  *
 711  * The command validator needs to reference BOs by their index within
 712  * the submitted job's BO list.  This does the validation of the job's
 713  * BO list and reference counting for the lifetime of the job.
 714  */
 715 static int
 716 vc4_cl_lookup_bos(struct drm_device *dev,
 717                   struct drm_file *file_priv,
 718                   struct vc4_exec_info *exec)
 719 {
 720         struct drm_vc4_submit_cl *args = exec->args;
 721         uint32_t *handles;
 722         int ret = 0;
 723         int i;
 724
 725         exec->bo_count = args->bo_handle_count;
 726
 727         if (!exec->bo_count) {
 728                 /* See comment on bo_index for why we have to check
 729                  * this.
 730                  */
 731                 DRM_DEBUG("Rendering requires BOs to validate\n");
 732                 return -EINVAL;
 733         }
 734
 735         exec->bo = kvmalloc_array(exec->bo_count,
 736                                     sizeof(struct drm_gem_cma_object *),
 737                                     GFP_KERNEL | __GFP_ZERO);
 738         if (!exec->bo) {
 739                 DRM_ERROR("Failed to allocate validated BO pointers\n");
 740                 return -ENOMEM;
 741         }
 742
 743         handles = kvmalloc_array(exec->bo_count, sizeof(uint32_t), GFP_KERNEL);
 744         if (!handles) {
 745                 ret = -ENOMEM;
 746                 DRM_ERROR("Failed to allocate incoming GEM handles\n");
 747                 goto fail;
 748         }
 749
 750         if (copy_from_user(handles, u64_to_user_ptr(args->bo_handles),
 751                            exec->bo_count * sizeof(uint32_t))) {
 752                 ret = -EFAULT;
 753                 DRM_ERROR("Failed to copy in GEM handles\n");
 754                 goto fail;
 755         }
 756
 757         spin_lock(&file_priv->table_lock);
 758         for (i = 0; i < exec->bo_count; i++) {
 759                 struct drm_gem_object *bo = idr_find(&file_priv->object_idr,
 760                                                      handles[i]);
 761                 if (!bo) {
 762                         DRM_DEBUG("Failed to look up GEM BO %d: %d\n",
 763                                   i, handles[i]);
 764                         ret = -EINVAL;
 765                         break;
 766                 }
 767
 768                 drm_gem_object_get(bo);
 769                 exec->bo[i] = (struct drm_gem_cma_object *)bo;
 770         }
 771         spin_unlock(&file_priv->table_lock);
 772
 773         if (ret)
 774                 goto fail_put_bo;
 775
 776         for (i = 0; i < exec->bo_count; i++) {
 777                 ret = vc4_bo_inc_usecnt(to_vc4_bo(&exec->bo[i]->base));
 778                 if (ret)
 779                         goto fail_dec_usecnt;
 780         }
 781
 782         kvfree(handles);
 783         return 0;
 784
 785 fail_dec_usecnt:
 786         /* Decrease usecnt on acquired objects.
 787          * We cannot rely on  vc4_complete_exec() to release resources here,
 788          * because vc4_complete_exec() has no information about which BO has
 789          * had its ->usecnt incremented.
 790          * To make things easier we just free everything explicitly and set
 791          * exec->bo to NULL so that vc4_complete_exec() skips the 'BO release'
 792          * step.
 793          */
 794         for (i-- ; i >= 0; i--)
 795                 vc4_bo_dec_usecnt(to_vc4_bo(&exec->bo[i]->base));
 796
 797 fail_put_bo:
 798         /* Release any reference to acquired objects. */
 799         for (i = 0; i < exec->bo_count && exec->bo[i]; i++)
 800                 drm_gem_object_put_unlocked(&exec->bo[i]->base);
 801
 802 fail:
 803         kvfree(handles);
 804         kvfree(exec->bo);
 805         exec->bo = NULL;
 806         return ret;
 807 }
 808
 809 static int
 810 vc4_get_bcl(struct drm_device *dev, struct vc4_exec_info *exec)
 811 {
 812         struct drm_vc4_submit_cl *args = exec->args;
 813         void *temp = NULL;
 814         void *bin;
 815         int ret = 0;
 816         uint32_t bin_offset = 0;
 817         uint32_t shader_rec_offset = roundup(bin_offset + args->bin_cl_size,
 818                                              16);
 819         uint32_t uniforms_offset = shader_rec_offset + args->shader_rec_size;
 820         uint32_t exec_size = uniforms_offset + args->uniforms_size;
 821         uint32_t temp_size = exec_size + (sizeof(struct vc4_shader_state) *
 822                                           args->shader_rec_count);
 823         struct vc4_bo *bo;
 824
 825         if (shader_rec_offset < args->bin_cl_size ||
 826             uniforms_offset < shader_rec_offset ||
 827             exec_size < uniforms_offset ||
 828             args->shader_rec_count >= (UINT_MAX /
 829                                           sizeof(struct vc4_shader_state)) ||
 830             temp_size < exec_size) {
 831                 DRM_DEBUG("overflow in exec arguments\n");
 832                 ret = -EINVAL;
 833                 goto fail;
 834         }
 835
 836         /* Allocate space where we'll store the copied in user command lists
 837          * and shader records.
 838          *
 839          * We don't just copy directly into the BOs because we need to
 840          * read the contents back for validation, and I think the
 841          * bo->vaddr is uncached access.
 842          */
 843         temp = kvmalloc_array(temp_size, 1, GFP_KERNEL);
 844         if (!temp) {
 845                 DRM_ERROR("Failed to allocate storage for copying "
 846                           "in bin/render CLs.\n");
 847                 ret = -ENOMEM;
 848                 goto fail;
 849         }
 850         bin = temp + bin_offset;
 851         exec->shader_rec_u = temp + shader_rec_offset;
 852         exec->uniforms_u = temp + uniforms_offset;
 853         exec->shader_state = temp + exec_size;
 854         exec->shader_state_size = args->shader_rec_count;
 855
 856         if (copy_from_user(bin,
 857                            u64_to_user_ptr(args->bin_cl),
 858                            args->bin_cl_size)) {
 859                 ret = -EFAULT;
 860                 goto fail;
 861         }
 862
 863         if (copy_from_user(exec->shader_rec_u,
 864                            u64_to_user_ptr(args->shader_rec),
 865                            args->shader_rec_size)) {
 866                 ret = -EFAULT;
 867                 goto fail;
 868         }
 869
 870         if (copy_from_user(exec->uniforms_u,
 871                            u64_to_user_ptr(args->uniforms),
 872                            args->uniforms_size)) {
 873                 ret = -EFAULT;
 874                 goto fail;
 875         }
 876
 877         bo = vc4_bo_create(dev, exec_size, true, VC4_BO_TYPE_BCL);
 878         if (IS_ERR(bo)) {
 879                 DRM_ERROR("Couldn't allocate BO for binning\n");
 880                 ret = PTR_ERR(bo);
 881                 goto fail;
 882         }
 883         exec->exec_bo = &bo->base;
 884
 885         list_add_tail(&to_vc4_bo(&exec->exec_bo->base)->unref_head,
 886                       &exec->unref_list);
 887
 888         exec->ct0ca = exec->exec_bo->paddr + bin_offset;
 889
 890         exec->bin_u = bin;
 891
 892         exec->shader_rec_v = exec->exec_bo->vaddr + shader_rec_offset;
 893         exec->shader_rec_p = exec->exec_bo->paddr + shader_rec_offset;
 894         exec->shader_rec_size = args->shader_rec_size;
 895
 896         exec->uniforms_v = exec->exec_bo->vaddr + uniforms_offset;
 897         exec->uniforms_p = exec->exec_bo->paddr + uniforms_offset;
 898         exec->uniforms_size = args->uniforms_size;
 899
 900         ret = vc4_validate_bin_cl(dev,
 901                                   exec->exec_bo->vaddr + bin_offset,
 902                                   bin,
 903                                   exec);
 904         if (ret)
 905                 goto fail;
 906
 907         ret = vc4_validate_shader_recs(dev, exec);
 908         if (ret)
 909                 goto fail;
 910
 911         /* Block waiting on any previous rendering into the CS's VBO,
 912          * IB, or textures, so that pixels are actually written by the
 913          * time we try to read them.
 914          */
 915         ret = vc4_wait_for_seqno(dev, exec->bin_dep_seqno, ~0ull, true);
 916
 917 fail:
 918         kvfree(temp);
 919         return ret;
 920 }
 921
 922 static void
 923 vc4_complete_exec(struct drm_device *dev, struct vc4_exec_info *exec)
 924 {
 925         struct vc4_dev *vc4 = to_vc4_dev(dev);
 926         unsigned long irqflags;
 927         unsigned i;
 928
 929         /* If we got force-completed because of GPU reset rather than
 930          * through our IRQ handler, signal the fence now.
 931          */
 932         if (exec->fence) {
 933                 dma_fence_signal(exec->fence);
 934                 dma_fence_put(exec->fence);
 935         }
 936
 937         if (exec->bo) {
 938                 for (i = 0; i < exec->bo_count; i++) {
 939                         struct vc4_bo *bo = to_vc4_bo(&exec->bo[i]->base);
 940
 941                         vc4_bo_dec_usecnt(bo);
 942                         drm_gem_object_put_unlocked(&exec->bo[i]->base);
 943                 }
 944                 kvfree(exec->bo);
 945         }
 946
 947         while (!list_empty(&exec->unref_list)) {
 948                 struct vc4_bo *bo = list_first_entry(&exec->unref_list,
 949                                                      struct vc4_bo, unref_head);
 950                 list_del(&bo->unref_head);
 951                 drm_gem_object_put_unlocked(&bo->base.base);
 952         }
 953
 954         /* Free up the allocation of any bin slots we used. */
 955         spin_lock_irqsave(&vc4->job_lock, irqflags);
 956         vc4->bin_alloc_used &= ~exec->bin_slots;
 957         spin_unlock_irqrestore(&vc4->job_lock, irqflags);
 958
 959         /* Release the reference we had on the perf monitor. */
 960         vc4_perfmon_put(exec->perfmon);
 961
 962         mutex_lock(&vc4->power_lock);
 963         if (--vc4->power_refcount == 0) {
 964                 pm_runtime_mark_last_busy(&vc4->v3d->pdev->dev);
 965                 pm_runtime_put_autosuspend(&vc4->v3d->pdev->dev);
 966         }
 967         mutex_unlock(&vc4->power_lock);
 968
 969         kfree(exec);
 970 }
 971
 972 void
 973 vc4_job_handle_completed(struct vc4_dev *vc4)
 974 {
 975         unsigned long irqflags;
 976         struct vc4_seqno_cb *cb, *cb_temp;
 977
 978         spin_lock_irqsave(&vc4->job_lock, irqflags);
 979         while (!list_empty(&vc4->job_done_list)) {
 980                 struct vc4_exec_info *exec =
 981                         list_first_entry(&vc4->job_done_list,
 982                                          struct vc4_exec_info, head);
 983                 list_del(&exec->head);
 984
 985                 spin_unlock_irqrestore(&vc4->job_lock, irqflags);
 986                 vc4_complete_exec(vc4->dev, exec);
 987                 spin_lock_irqsave(&vc4->job_lock, irqflags);
 988         }
 989
 990         list_for_each_entry_safe(cb, cb_temp, &vc4->seqno_cb_list, work.entry) {
 991                 if (cb->seqno <= vc4->finished_seqno) {
 992                         list_del_init(&cb->work.entry);
 993                         schedule_work(&cb->work);
 994                 }
 995         }
 996
 997         spin_unlock_irqrestore(&vc4->job_lock, irqflags);
 998 }
 999
1000 static void vc4_seqno_cb_work(struct work_struct *work)
1001 {
1002         struct vc4_seqno_cb *cb = container_of(work, struct vc4_seqno_cb, work);
1003
1004         cb->func(cb);
1005 }
1006
1007 int vc4_queue_seqno_cb(struct drm_device *dev,
1008                        struct vc4_seqno_cb *cb, uint64_t seqno,
1009                        void (*func)(struct vc4_seqno_cb *cb))
1010 {
1011         struct vc4_dev *vc4 = to_vc4_dev(dev);
1012         int ret = 0;
1013         unsigned long irqflags;
1014
1015         cb->func = func;
1016         INIT_WORK(&cb->work, vc4_seqno_cb_work);
1017
1018         spin_lock_irqsave(&vc4->job_lock, irqflags);
1019         if (seqno > vc4->finished_seqno) {
1020                 cb->seqno = seqno;
1021                 list_add_tail(&cb->work.entry, &vc4->seqno_cb_list);
1022         } else {
1023                 schedule_work(&cb->work);
1024         }
1025         spin_unlock_irqrestore(&vc4->job_lock, irqflags);
1026
1027         return ret;
1028 }
1029
1030 /* Scheduled when any job has been completed, this walks the list of
1031  * jobs that had completed and unrefs their BOs and frees their exec
1032  * structs.
1033  */
1034 static void
1035 vc4_job_done_work(struct work_struct *work)
1036 {
1037         struct vc4_dev *vc4 =
1038                 container_of(work, struct vc4_dev, job_done_work);
1039
1040         vc4_job_handle_completed(vc4);
1041 }
1042
1043 static int
1044 vc4_wait_for_seqno_ioctl_helper(struct drm_device *dev,
1045                                 uint64_t seqno,
1046                                 uint64_t *timeout_ns)
1047 {
1048         unsigned long start = jiffies;
1049         int ret = vc4_wait_for_seqno(dev, seqno, *timeout_ns, true);
1050
1051         if ((ret == -EINTR || ret == -ERESTARTSYS) && *timeout_ns != ~0ull) {
1052                 uint64_t delta = jiffies_to_nsecs(jiffies - start);
1053
1054                 if (*timeout_ns >= delta)
1055                         *timeout_ns -= delta;
1056         }
1057
1058         return ret;
1059 }
1060
1061 int
1062 vc4_wait_seqno_ioctl(struct drm_device *dev, void *data,
1063                      struct drm_file *file_priv)
1064 {
1065         struct drm_vc4_wait_seqno *args = data;
1066
1067         return vc4_wait_for_seqno_ioctl_helper(dev, args->seqno,
1068                                                &args->timeout_ns);
1069 }
1070
1071 int
1072 vc4_wait_bo_ioctl(struct drm_device *dev, void *data,
1073                   struct drm_file *file_priv)
1074 {
1075         int ret;
1076         struct drm_vc4_wait_bo *args = data;
1077         struct drm_gem_object *gem_obj;
1078         struct vc4_bo *bo;
1079
1080         if (args->pad != 0)
1081                 return -EINVAL;
1082
1083         gem_obj = drm_gem_object_lookup(file_priv, args->handle);
1084         if (!gem_obj) {
1085                 DRM_DEBUG("Failed to look up GEM BO %d\n", args->handle);
1086                 return -EINVAL;
1087         }
1088         bo = to_vc4_bo(gem_obj);
1089
1090         ret = vc4_wait_for_seqno_ioctl_helper(dev, bo->seqno,
1091                                               &args->timeout_ns);
1092
1093         drm_gem_object_put_unlocked(gem_obj);
1094         return ret;
1095 }
1096
1097 /**
1098  * vc4_submit_cl_ioctl() - Submits a job (frame) to the VC4.
1099  * @dev: DRM device
1100  * @data: ioctl argument
1101  * @file_priv: DRM file for this fd
1102  *
1103  * This is the main entrypoint for userspace to submit a 3D frame to
1104  * the GPU.  Userspace provides the binner command list (if
1105  * applicable), and the kernel sets up the render command list to draw
1106  * to the framebuffer described in the ioctl, using the command lists
1107  * that the 3D engine's binner will produce.
1108  */
1109 int
1110 vc4_submit_cl_ioctl(struct drm_device *dev, void *data,
1111                     struct drm_file *file_priv)
1112 {
1113         struct vc4_dev *vc4 = to_vc4_dev(dev);
1114         struct vc4_file *vc4file = file_priv->driver_priv;
1115         struct drm_vc4_submit_cl *args = data;
1116         struct vc4_exec_info *exec;
1117         struct ww_acquire_ctx acquire_ctx;
1118         int ret = 0;
1119
1120         if ((args->flags & ~(VC4_SUBMIT_CL_USE_CLEAR_COLOR |
1121                              VC4_SUBMIT_CL_FIXED_RCL_ORDER |
1122                              VC4_SUBMIT_CL_RCL_ORDER_INCREASING_X |
1123                              VC4_SUBMIT_CL_RCL_ORDER_INCREASING_Y)) != 0) {
1124                 DRM_DEBUG("Unknown flags: 0x%02x\n", args->flags);
1125                 return -EINVAL;
1126         }
1127
1128         if (args->pad2 != 0) {
1129                 DRM_DEBUG("->pad2 must be set to zero\n");
1130                 return -EINVAL;
1131         }
1132
1133         exec = kcalloc(1, sizeof(*exec), GFP_KERNEL);
1134         if (!exec) {
1135                 DRM_ERROR("malloc failure on exec struct\n");
1136                 return -ENOMEM;
1137         }
1138
1139         mutex_lock(&vc4->power_lock);
1140         if (vc4->power_refcount++ == 0) {
1141                 ret = pm_runtime_get_sync(&vc4->v3d->pdev->dev);
1142                 if (ret < 0) {
1143                         mutex_unlock(&vc4->power_lock);
1144                         vc4->power_refcount--;
1145                         kfree(exec);
1146                         return ret;
1147                 }
1148         }
1149         mutex_unlock(&vc4->power_lock);
1150
1151         exec->args = args;
1152         INIT_LIST_HEAD(&exec->unref_list);
1153
1154         ret = vc4_cl_lookup_bos(dev, file_priv, exec);
1155         if (ret)
1156                 goto fail;
1157
1158         if (args->perfmonid) {
1159                 exec->perfmon = vc4_perfmon_find(vc4file,
1160                                                  args->perfmonid);
1161                 if (!exec->perfmon) {
1162                         ret = -ENOENT;
1163                         goto fail;
1164                 }
1165         }
1166
1167         if (exec->args->bin_cl_size != 0) {
1168                 ret = vc4_get_bcl(dev, exec);
1169                 if (ret)
1170                         goto fail;
1171         } else {
1172                 exec->ct0ca = 0;
1173                 exec->ct0ea = 0;
1174         }
1175
1176         ret = vc4_get_rcl(dev, exec);
1177         if (ret)
1178                 goto fail;
1179
1180         ret = vc4_lock_bo_reservations(dev, exec, &acquire_ctx);
1181         if (ret)
1182                 goto fail;
1183
1184         /* Clear this out of the struct we'll be putting in the queue,
1185          * since it's part of our stack.
1186          */
1187         exec->args = NULL;
1188
1189         ret = vc4_queue_submit(dev, exec, &acquire_ctx);
1190         if (ret)
1191                 goto fail;
1192
1193         /* Return the seqno for our job. */
1194         args->seqno = vc4->emit_seqno;
1195
1196         return 0;
1197
1198 fail:
1199         vc4_complete_exec(vc4->dev, exec);
1200
1201         return ret;
1202 }
1203
1204 void
1205 vc4_gem_init(struct drm_device *dev)
1206 {
1207         struct vc4_dev *vc4 = to_vc4_dev(dev);
1208
1209         vc4->dma_fence_context = dma_fence_context_alloc(1);
1210
1211         INIT_LIST_HEAD(&vc4->bin_job_list);
1212         INIT_LIST_HEAD(&vc4->render_job_list);
1213         INIT_LIST_HEAD(&vc4->job_done_list);
1214         INIT_LIST_HEAD(&vc4->seqno_cb_list);
1215         spin_lock_init(&vc4->job_lock);
1216
1217         INIT_WORK(&vc4->hangcheck.reset_work, vc4_reset_work);
1218         timer_setup(&vc4->hangcheck.timer, vc4_hangcheck_elapsed, 0);
1219
1220         INIT_WORK(&vc4->job_done_work, vc4_job_done_work);
1221
1222         mutex_init(&vc4->power_lock);
1223
1224         INIT_LIST_HEAD(&vc4->purgeable.list);
1225         mutex_init(&vc4->purgeable.lock);
1226 }
1227
1228 void
1229 vc4_gem_destroy(struct drm_device *dev)
1230 {
1231         struct vc4_dev *vc4 = to_vc4_dev(dev);
1232
1233         /* Waiting for exec to finish would need to be done before
1234          * unregistering V3D.
1235          */
1236         WARN_ON(vc4->emit_seqno != vc4->finished_seqno);
1237
1238         /* V3D should already have disabled its interrupt and cleared
1239          * the overflow allocation registers.  Now free the object.
1240          */
1241         if (vc4->bin_bo) {
1242                 drm_gem_object_put_unlocked(&vc4->bin_bo->base.base);
1243                 vc4->bin_bo = NULL;
1244         }
1245
1246         if (vc4->hang_state)
1247                 vc4_free_hang_state(dev, vc4->hang_state);
1248 }
1249
1250 int vc4_gem_madvise_ioctl(struct drm_device *dev, void *data,
1251                           struct drm_file *file_priv)
1252 {
1253         struct drm_vc4_gem_madvise *args = data;
1254         struct drm_gem_object *gem_obj;
1255         struct vc4_bo *bo;
1256         int ret;
1257
1258         switch (args->madv) {
1259         case VC4_MADV_DONTNEED:
1260         case VC4_MADV_WILLNEED:
1261                 break;
1262         default:
1263                 return -EINVAL;
1264         }
1265
1266         if (args->pad != 0)
1267                 return -EINVAL;
1268
1269         gem_obj = drm_gem_object_lookup(file_priv, args->handle);
1270         if (!gem_obj) {
1271                 DRM_DEBUG("Failed to look up GEM BO %d\n", args->handle);
1272                 return -ENOENT;
1273         }
1274
1275         bo = to_vc4_bo(gem_obj);
1276
1277         /* Only BOs exposed to userspace can be purged. */
1278         if (bo->madv == __VC4_MADV_NOTSUPP) {
1279                 DRM_DEBUG("madvise not supported on this BO\n");
1280                 ret = -EINVAL;
1281                 goto out_put_gem;
1282         }
1283
1284         /* Not sure it's safe to purge imported BOs. Let's just assume it's
1285          * not until proven otherwise.
1286          */
1287         if (gem_obj->import_attach) {
1288                 DRM_DEBUG("madvise not supported on imported BOs\n");
1289                 ret = -EINVAL;
1290                 goto out_put_gem;
1291         }
1292
1293         mutex_lock(&bo->madv_lock);
1294
1295         if (args->madv == VC4_MADV_DONTNEED && bo->madv == VC4_MADV_WILLNEED &&
1296             !refcount_read(&bo->usecnt)) {
1297                 /* If the BO is about to be marked as purgeable, is not used
1298                  * and is not already purgeable or purged, add it to the
1299                  * purgeable list.
1300                  */
1301                 vc4_bo_add_to_purgeable_pool(bo);
1302         } else if (args->madv == VC4_MADV_WILLNEED &&
1303                    bo->madv == VC4_MADV_DONTNEED &&
1304                    !refcount_read(&bo->usecnt)) {
1305                 /* The BO has not been purged yet, just remove it from
1306                  * the purgeable list.
1307                  */
1308                 vc4_bo_remove_from_purgeable_pool(bo);
1309         }
1310
1311         /* Save the purged state. */
1312         args->retained = bo->madv != __VC4_MADV_PURGED;
1313
1314         /* Update internal madv state only if the bo was not purged. */
1315         if (bo->madv != __VC4_MADV_PURGED)
1316                 bo->madv = args->madv;
1317
1318         mutex_unlock(&bo->madv_lock);
1319
1320         ret = 0;
1321
1322 out_put_gem:
1323         drm_gem_object_put_unlocked(gem_obj);
1324
1325         return ret;
1326 }