drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c

   1 /*
   2  * Copyright 2014 Advanced Micro Devices, Inc.
   3  * All Rights Reserved.
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining a
   6  * copy of this software and associated documentation files (the
   7  * "Software"), to deal in the Software without restriction, including
   8  * without limitation the rights to use, copy, modify, merge, publish,
   9  * distribute, sub license, and/or sell copies of the Software, and to
  10  * permit persons to whom the Software is furnished to do so, subject to
  11  * the following conditions:
  12  *
  13  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  14  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  15  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
  16  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
  17  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
  18  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
  19  * USE OR OTHER DEALINGS IN THE SOFTWARE.
  20  *
  21  * The above copyright notice and this permission notice (including the
  22  * next paragraph) shall be included in all copies or substantial portions
  23  * of the Software.
  24  *
  25  */
  26 /*
  27  * Authors:
  28  *    Christian König <christian.koenig@amd.com>
  29  */
  30
  31 #include <linux/firmware.h>
  32 #include <linux/module.h>
  33 #include <linux/mmu_notifier.h>
  34 #include <drm/drmP.h>
  35 #include <drm/drm.h>
  36
  37 #include "amdgpu.h"
  38
  39 struct amdgpu_mn {
  40         /* constant after initialisation */
  41         struct amdgpu_device    *adev;
  42         struct mm_struct        *mm;
  43         struct mmu_notifier     mn;
  44
  45         /* only used on destruction */
  46         struct work_struct      work;
  47
  48         /* protected by adev->mn_lock */
  49         struct hlist_node       node;
  50
  51         /* objects protected by lock */
  52         struct mutex            lock;
  53         struct rb_root          objects;
  54 };
  55
  56 struct amdgpu_mn_node {
  57         struct interval_tree_node       it;
  58         struct list_head                bos;
  59 };
  60
  61 /**
  62  * amdgpu_mn_destroy - destroy the rmn
  63  *
  64  * @work: previously sheduled work item
  65  *
  66  * Lazy destroys the notifier from a work item
  67  */
  68 static void amdgpu_mn_destroy(struct work_struct *work)
  69 {
  70         struct amdgpu_mn *rmn = container_of(work, struct amdgpu_mn, work);
  71         struct amdgpu_device *adev = rmn->adev;
  72         struct amdgpu_mn_node *node, *next_node;
  73         struct amdgpu_bo *bo, *next_bo;
  74
  75         mutex_lock(&adev->mn_lock);
  76         mutex_lock(&rmn->lock);
  77         hash_del(&rmn->node);
  78         rbtree_postorder_for_each_entry_safe(node, next_node, &rmn->objects,
  79                                              it.rb) {
  80                 list_for_each_entry_safe(bo, next_bo, &node->bos, mn_list) {
  81                         bo->mn = NULL;
  82                         list_del_init(&bo->mn_list);
  83                 }
  84                 kfree(node);
  85         }
  86         mutex_unlock(&rmn->lock);
  87         mutex_unlock(&adev->mn_lock);
  88         mmu_notifier_unregister_no_release(&rmn->mn, rmn->mm);
  89         kfree(rmn);
  90 }
  91
  92 /**
  93  * amdgpu_mn_release - callback to notify about mm destruction
  94  *
  95  * @mn: our notifier
  96  * @mn: the mm this callback is about
  97  *
  98  * Shedule a work item to lazy destroy our notifier.
  99  */
 100 static void amdgpu_mn_release(struct mmu_notifier *mn,
 101                               struct mm_struct *mm)
 102 {
 103         struct amdgpu_mn *rmn = container_of(mn, struct amdgpu_mn, mn);
 104         INIT_WORK(&rmn->work, amdgpu_mn_destroy);
 105         schedule_work(&rmn->work);
 106 }
 107
 108 /**
 109  * amdgpu_mn_invalidate_node - unmap all BOs of a node
 110  *
 111  * @node: the node with the BOs to unmap
 112  *
 113  * We block for all BOs and unmap them by move them
 114  * into system domain again.
 115  */
 116 static void amdgpu_mn_invalidate_node(struct amdgpu_mn_node *node,
 117                                       unsigned long start,
 118                                       unsigned long end)
 119 {
 120         struct amdgpu_bo *bo;
 121         long r;
 122
 123         list_for_each_entry(bo, &node->bos, mn_list) {
 124
 125                 if (!amdgpu_ttm_tt_affect_userptr(bo->tbo.ttm, start, end))
 126                         continue;
 127
 128                 r = amdgpu_bo_reserve(bo, true);
 129                 if (r) {
 130                         DRM_ERROR("(%ld) failed to reserve user bo\n", r);
 131                         continue;
 132                 }
 133
 134                 r = reservation_object_wait_timeout_rcu(bo->tbo.resv,
 135                         true, false, MAX_SCHEDULE_TIMEOUT);
 136                 if (r <= 0)
 137                         DRM_ERROR("(%ld) failed to wait for user bo\n", r);
 138
 139                 amdgpu_ttm_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_CPU);
 140                 r = ttm_bo_validate(&bo->tbo, &bo->placement, false, false);
 141                 if (r)
 142                         DRM_ERROR("(%ld) failed to validate user bo\n", r);
 143
 144                 amdgpu_bo_unreserve(bo);
 145         }
 146 }
 147
 148 /**
 149  * amdgpu_mn_invalidate_page - callback to notify about mm change
 150  *
 151  * @mn: our notifier
 152  * @mn: the mm this callback is about
 153  * @address: address of invalidate page
 154  *
 155  * Invalidation of a single page. Blocks for all BOs mapping it
 156  * and unmap them by move them into system domain again.
 157  */
 158 static void amdgpu_mn_invalidate_page(struct mmu_notifier *mn,
 159                                       struct mm_struct *mm,
 160                                       unsigned long address)
 161 {
 162         struct amdgpu_mn *rmn = container_of(mn, struct amdgpu_mn, mn);
 163         struct interval_tree_node *it;
 164
 165         mutex_lock(&rmn->lock);
 166
 167         it = interval_tree_iter_first(&rmn->objects, address, address);
 168         if (it) {
 169                 struct amdgpu_mn_node *node;
 170
 171                 node = container_of(it, struct amdgpu_mn_node, it);
 172                 amdgpu_mn_invalidate_node(node, address, address);
 173         }
 174
 175         mutex_unlock(&rmn->lock);
 176 }
 177
 178 /**
 179  * amdgpu_mn_invalidate_range_start - callback to notify about mm change
 180  *
 181  * @mn: our notifier
 182  * @mn: the mm this callback is about
 183  * @start: start of updated range
 184  * @end: end of updated range
 185  *
 186  * We block for all BOs between start and end to be idle and
 187  * unmap them by move them into system domain again.
 188  */
 189 static void amdgpu_mn_invalidate_range_start(struct mmu_notifier *mn,
 190                                              struct mm_struct *mm,
 191                                              unsigned long start,
 192                                              unsigned long end)
 193 {
 194         struct amdgpu_mn *rmn = container_of(mn, struct amdgpu_mn, mn);
 195         struct interval_tree_node *it;
 196
 197         /* notification is exclusive, but interval is inclusive */
 198         end -= 1;
 199
 200         mutex_lock(&rmn->lock);
 201
 202         it = interval_tree_iter_first(&rmn->objects, start, end);
 203         while (it) {
 204                 struct amdgpu_mn_node *node;
 205
 206                 node = container_of(it, struct amdgpu_mn_node, it);
 207                 it = interval_tree_iter_next(it, start, end);
 208
 209                 amdgpu_mn_invalidate_node(node, start, end);
 210         }
 211
 212         mutex_unlock(&rmn->lock);
 213 }
 214
 215 static const struct mmu_notifier_ops amdgpu_mn_ops = {
 216         .release = amdgpu_mn_release,
 217         .invalidate_page = amdgpu_mn_invalidate_page,
 218         .invalidate_range_start = amdgpu_mn_invalidate_range_start,
 219 };
 220
 221 /**
 222  * amdgpu_mn_get - create notifier context
 223  *
 224  * @adev: amdgpu device pointer
 225  *
 226  * Creates a notifier context for current->mm.
 227  */
 228 static struct amdgpu_mn *amdgpu_mn_get(struct amdgpu_device *adev)
 229 {
 230         struct mm_struct *mm = current->mm;
 231         struct amdgpu_mn *rmn;
 232         int r;
 233
 234         mutex_lock(&adev->mn_lock);
 235         if (down_write_killable(&mm->mmap_sem)) {
 236                 mutex_unlock(&adev->mn_lock);
 237                 return ERR_PTR(-EINTR);
 238         }
 239
 240         hash_for_each_possible(adev->mn_hash, rmn, node, (unsigned long)mm)
 241                 if (rmn->mm == mm)
 242                         goto release_locks;
 243
 244         rmn = kzalloc(sizeof(*rmn), GFP_KERNEL);
 245         if (!rmn) {
 246                 rmn = ERR_PTR(-ENOMEM);
 247                 goto release_locks;
 248         }
 249
 250         rmn->adev = adev;
 251         rmn->mm = mm;
 252         rmn->mn.ops = &amdgpu_mn_ops;
 253         mutex_init(&rmn->lock);
 254         rmn->objects = RB_ROOT;
 255
 256         r = __mmu_notifier_register(&rmn->mn, mm);
 257         if (r)
 258                 goto free_rmn;
 259
 260         hash_add(adev->mn_hash, &rmn->node, (unsigned long)mm);
 261
 262 release_locks:
 263         up_write(&mm->mmap_sem);
 264         mutex_unlock(&adev->mn_lock);
 265
 266         return rmn;
 267
 268 free_rmn:
 269         up_write(&mm->mmap_sem);
 270         mutex_unlock(&adev->mn_lock);
 271         kfree(rmn);
 272
 273         return ERR_PTR(r);
 274 }
 275
 276 /**
 277  * amdgpu_mn_register - register a BO for notifier updates
 278  *
 279  * @bo: amdgpu buffer object
 280  * @addr: userptr addr we should monitor
 281  *
 282  * Registers an MMU notifier for the given BO at the specified address.
 283  * Returns 0 on success, -ERRNO if anything goes wrong.
 284  */
 285 int amdgpu_mn_register(struct amdgpu_bo *bo, unsigned long addr)
 286 {
 287         unsigned long end = addr + amdgpu_bo_size(bo) - 1;
 288         struct amdgpu_device *adev = amdgpu_ttm_adev(bo->tbo.bdev);
 289         struct amdgpu_mn *rmn;
 290         struct amdgpu_mn_node *node = NULL;
 291         struct list_head bos;
 292         struct interval_tree_node *it;
 293
 294         rmn = amdgpu_mn_get(adev);
 295         if (IS_ERR(rmn))
 296                 return PTR_ERR(rmn);
 297
 298         INIT_LIST_HEAD(&bos);
 299
 300         mutex_lock(&rmn->lock);
 301
 302         while ((it = interval_tree_iter_first(&rmn->objects, addr, end))) {
 303                 kfree(node);
 304                 node = container_of(it, struct amdgpu_mn_node, it);
 305                 interval_tree_remove(&node->it, &rmn->objects);
 306                 addr = min(it->start, addr);
 307                 end = max(it->last, end);
 308                 list_splice(&node->bos, &bos);
 309         }
 310
 311         if (!node) {
 312                 node = kmalloc(sizeof(struct amdgpu_mn_node), GFP_KERNEL);
 313                 if (!node) {
 314                         mutex_unlock(&rmn->lock);
 315                         return -ENOMEM;
 316                 }
 317         }
 318
 319         bo->mn = rmn;
 320
 321         node->it.start = addr;
 322         node->it.last = end;
 323         INIT_LIST_HEAD(&node->bos);
 324         list_splice(&bos, &node->bos);
 325         list_add(&bo->mn_list, &node->bos);
 326
 327         interval_tree_insert(&node->it, &rmn->objects);
 328
 329         mutex_unlock(&rmn->lock);
 330
 331         return 0;
 332 }
 333
 334 /**
 335  * amdgpu_mn_unregister - unregister a BO for notifier updates
 336  *
 337  * @bo: amdgpu buffer object
 338  *
 339  * Remove any registration of MMU notifier updates from the buffer object.
 340  */
 341 void amdgpu_mn_unregister(struct amdgpu_bo *bo)
 342 {
 343         struct amdgpu_device *adev = amdgpu_ttm_adev(bo->tbo.bdev);
 344         struct amdgpu_mn *rmn;
 345         struct list_head *head;
 346
 347         mutex_lock(&adev->mn_lock);
 348
 349         rmn = bo->mn;
 350         if (rmn == NULL) {
 351                 mutex_unlock(&adev->mn_lock);
 352                 return;
 353         }
 354
 355         mutex_lock(&rmn->lock);
 356
 357         /* save the next list entry for later */
 358         head = bo->mn_list.next;
 359
 360         bo->mn = NULL;
 361         list_del(&bo->mn_list);
 362
 363         if (list_empty(head)) {
 364                 struct amdgpu_mn_node *node;
 365                 node = container_of(head, struct amdgpu_mn_node, bos);
 366                 interval_tree_remove(&node->it, &rmn->objects);
 367                 kfree(node);
 368         }
 369
 370         mutex_unlock(&rmn->lock);
 371         mutex_unlock(&adev->mn_lock);
 372 }