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