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 <linux/interval_tree.h>
  35 #include <drm/drmP.h>
  36 #include <drm/drm.h>
  37
  38 #include "amdgpu.h"
  39
  40 struct amdgpu_mn {
  41         /* constant after initialisation */
  42         struct amdgpu_device    *adev;
  43         struct mm_struct        *mm;
  44         struct mmu_notifier     mn;
  45
  46         /* only used on destruction */
  47         struct work_struct      work;
  48
  49         /* protected by adev->mn_lock */
  50         struct hlist_node       node;
  51
  52         /* objects protected by lock */
  53         struct mutex            lock;
  54         struct rb_root          objects;
  55 };
  56
  57 struct amdgpu_mn_node {
  58         struct interval_tree_node       it;
  59         struct list_head                bos;
  60 };
  61
  62 /**
  63  * amdgpu_mn_destroy - destroy the rmn
  64  *
  65  * @work: previously sheduled work item
  66  *
  67  * Lazy destroys the notifier from a work item
  68  */
  69 static void amdgpu_mn_destroy(struct work_struct *work)
  70 {
  71         struct amdgpu_mn *rmn = container_of(work, struct amdgpu_mn, work);
  72         struct amdgpu_device *adev = rmn->adev;
  73         struct amdgpu_mn_node *node, *next_node;
  74         struct amdgpu_bo *bo, *next_bo;
  75
  76         mutex_lock(&adev->mn_lock);
  77         mutex_lock(&rmn->lock);
  78         hash_del(&rmn->node);
  79         rbtree_postorder_for_each_entry_safe(node, next_node, &rmn->objects,
  80                                              it.rb) {
  81                 list_for_each_entry_safe(bo, next_bo, &node->bos, mn_list) {
  82                         bo->mn = NULL;
  83                         list_del_init(&bo->mn_list);
  84                 }
  85                 kfree(node);
  86         }
  87         mutex_unlock(&rmn->lock);
  88         mutex_unlock(&adev->mn_lock);
  89         mmu_notifier_unregister_no_release(&rmn->mn, rmn->mm);
  90         kfree(rmn);
  91 }
  92
  93 /**
  94  * amdgpu_mn_release - callback to notify about mm destruction
  95  *
  96  * @mn: our notifier
  97  * @mn: the mm this callback is about
  98  *
  99  * Shedule a work item to lazy destroy our notifier.
 100  */
 101 static void amdgpu_mn_release(struct mmu_notifier *mn,
 102                               struct mm_struct *mm)
 103 {
 104         struct amdgpu_mn *rmn = container_of(mn, struct amdgpu_mn, mn);
 105         INIT_WORK(&rmn->work, amdgpu_mn_destroy);
 106         schedule_work(&rmn->work);
 107 }
 108
 109 /**
 110  * amdgpu_mn_invalidate_node - unmap all BOs of a node
 111  *
 112  * @node: the node with the BOs to unmap
 113  *
 114  * We block for all BOs and unmap them by move them
 115  * into system domain again.
 116  */
 117 static void amdgpu_mn_invalidate_node(struct amdgpu_mn_node *node,
 118                                       unsigned long start,
 119                                       unsigned long end)
 120 {
 121         struct amdgpu_bo *bo;
 122         long r;
 123
 124         list_for_each_entry(bo, &node->bos, mn_list) {
 125
 126                 if (!amdgpu_ttm_tt_affect_userptr(bo->tbo.ttm, start, end))
 127                         continue;
 128
 129                 r = amdgpu_bo_reserve(bo, true);
 130                 if (r) {
 131                         DRM_ERROR("(%ld) failed to reserve user bo\n", r);
 132                         continue;
 133                 }
 134
 135                 r = reservation_object_wait_timeout_rcu(bo->tbo.resv,
 136                         true, false, MAX_SCHEDULE_TIMEOUT);
 137                 if (r <= 0)
 138                         DRM_ERROR("(%ld) failed to wait for user bo\n", r);
 139
 140                 amdgpu_ttm_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_CPU);
 141                 r = ttm_bo_validate(&bo->tbo, &bo->placement, false, false);
 142                 if (r)
 143                         DRM_ERROR("(%ld) failed to validate user bo\n", r);
 144
 145                 amdgpu_bo_unreserve(bo);
 146         }
 147 }
 148
 149 /**
 150  * amdgpu_mn_invalidate_range_start - callback to notify about mm change
 151  *
 152  * @mn: our notifier
 153  * @mn: the mm this callback is about
 154  * @start: start of updated range
 155  * @end: end of updated range
 156  *
 157  * We block for all BOs between start and end to be idle and
 158  * unmap them by move them into system domain again.
 159  */
 160 static void amdgpu_mn_invalidate_range_start(struct mmu_notifier *mn,
 161                                              struct mm_struct *mm,
 162                                              unsigned long start,
 163                                              unsigned long end)
 164 {
 165         struct amdgpu_mn *rmn = container_of(mn, struct amdgpu_mn, mn);
 166         struct interval_tree_node *it;
 167
 168         /* notification is exclusive, but interval is inclusive */
 169         end -= 1;
 170
 171         mutex_lock(&rmn->lock);
 172
 173         it = interval_tree_iter_first(&rmn->objects, start, end);
 174         while (it) {
 175                 struct amdgpu_mn_node *node;
 176
 177                 node = container_of(it, struct amdgpu_mn_node, it);
 178                 it = interval_tree_iter_next(it, start, end);
 179
 180                 amdgpu_mn_invalidate_node(node, start, end);
 181         }
 182
 183         mutex_unlock(&rmn->lock);
 184 }
 185
 186 static const struct mmu_notifier_ops amdgpu_mn_ops = {
 187         .release = amdgpu_mn_release,
 188         .invalidate_range_start = amdgpu_mn_invalidate_range_start,
 189 };
 190
 191 /**
 192  * amdgpu_mn_get - create notifier context
 193  *
 194  * @adev: amdgpu device pointer
 195  *
 196  * Creates a notifier context for current->mm.
 197  */
 198 static struct amdgpu_mn *amdgpu_mn_get(struct amdgpu_device *adev)
 199 {
 200         struct mm_struct *mm = current->mm;
 201         struct amdgpu_mn *rmn;
 202         int r;
 203
 204         mutex_lock(&adev->mn_lock);
 205         if (down_write_killable(&mm->mmap_sem)) {
 206                 mutex_unlock(&adev->mn_lock);
 207                 return ERR_PTR(-EINTR);
 208         }
 209
 210         hash_for_each_possible(adev->mn_hash, rmn, node, (unsigned long)mm)
 211                 if (rmn->mm == mm)
 212                         goto release_locks;
 213
 214         rmn = kzalloc(sizeof(*rmn), GFP_KERNEL);
 215         if (!rmn) {
 216                 rmn = ERR_PTR(-ENOMEM);
 217                 goto release_locks;
 218         }
 219
 220         rmn->adev = adev;
 221         rmn->mm = mm;
 222         rmn->mn.ops = &amdgpu_mn_ops;
 223         mutex_init(&rmn->lock);
 224         rmn->objects = RB_ROOT;
 225
 226         r = __mmu_notifier_register(&rmn->mn, mm);
 227         if (r)
 228                 goto free_rmn;
 229
 230         hash_add(adev->mn_hash, &rmn->node, (unsigned long)mm);
 231
 232 release_locks:
 233         up_write(&mm->mmap_sem);
 234         mutex_unlock(&adev->mn_lock);
 235
 236         return rmn;
 237
 238 free_rmn:
 239         up_write(&mm->mmap_sem);
 240         mutex_unlock(&adev->mn_lock);
 241         kfree(rmn);
 242
 243         return ERR_PTR(r);
 244 }
 245
 246 /**
 247  * amdgpu_mn_register - register a BO for notifier updates
 248  *
 249  * @bo: amdgpu buffer object
 250  * @addr: userptr addr we should monitor
 251  *
 252  * Registers an MMU notifier for the given BO at the specified address.
 253  * Returns 0 on success, -ERRNO if anything goes wrong.
 254  */
 255 int amdgpu_mn_register(struct amdgpu_bo *bo, unsigned long addr)
 256 {
 257         unsigned long end = addr + amdgpu_bo_size(bo) - 1;
 258         struct amdgpu_device *adev = amdgpu_ttm_adev(bo->tbo.bdev);
 259         struct amdgpu_mn *rmn;
 260         struct amdgpu_mn_node *node = NULL;
 261         struct list_head bos;
 262         struct interval_tree_node *it;
 263
 264         rmn = amdgpu_mn_get(adev);
 265         if (IS_ERR(rmn))
 266                 return PTR_ERR(rmn);
 267
 268         INIT_LIST_HEAD(&bos);
 269
 270         mutex_lock(&rmn->lock);
 271
 272         while ((it = interval_tree_iter_first(&rmn->objects, addr, end))) {
 273                 kfree(node);
 274                 node = container_of(it, struct amdgpu_mn_node, it);
 275                 interval_tree_remove(&node->it, &rmn->objects);
 276                 addr = min(it->start, addr);
 277                 end = max(it->last, end);
 278                 list_splice(&node->bos, &bos);
 279         }
 280
 281         if (!node) {
 282                 node = kmalloc(sizeof(struct amdgpu_mn_node), GFP_KERNEL);
 283                 if (!node) {
 284                         mutex_unlock(&rmn->lock);
 285                         return -ENOMEM;
 286                 }
 287         }
 288
 289         bo->mn = rmn;
 290
 291         node->it.start = addr;
 292         node->it.last = end;
 293         INIT_LIST_HEAD(&node->bos);
 294         list_splice(&bos, &node->bos);
 295         list_add(&bo->mn_list, &node->bos);
 296
 297         interval_tree_insert(&node->it, &rmn->objects);
 298
 299         mutex_unlock(&rmn->lock);
 300
 301         return 0;
 302 }
 303
 304 /**
 305  * amdgpu_mn_unregister - unregister a BO for notifier updates
 306  *
 307  * @bo: amdgpu buffer object
 308  *
 309  * Remove any registration of MMU notifier updates from the buffer object.
 310  */
 311 void amdgpu_mn_unregister(struct amdgpu_bo *bo)
 312 {
 313         struct amdgpu_device *adev = amdgpu_ttm_adev(bo->tbo.bdev);
 314         struct amdgpu_mn *rmn;
 315         struct list_head *head;
 316
 317         mutex_lock(&adev->mn_lock);
 318
 319         rmn = bo->mn;
 320         if (rmn == NULL) {
 321                 mutex_unlock(&adev->mn_lock);
 322                 return;
 323         }
 324
 325         mutex_lock(&rmn->lock);
 326
 327         /* save the next list entry for later */
 328         head = bo->mn_list.next;
 329
 330         bo->mn = NULL;
 331         list_del_init(&bo->mn_list);
 332
 333         if (list_empty(head)) {
 334                 struct amdgpu_mn_node *node;
 335                 node = container_of(head, struct amdgpu_mn_node, bos);
 336                 interval_tree_remove(&node->it, &rmn->objects);
 337                 kfree(node);
 338         }
 339
 340         mutex_unlock(&rmn->lock);
 341         mutex_unlock(&adev->mn_lock);
 342 }