1 files changed, 319 insertions, 0 deletions
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c
new file mode 100644
index 000000000000..e94429185660
--- /dev/null
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c
@@ -0,0 +1,319 @@
+/*
+ * Copyright 2014 Advanced Micro Devices, Inc.
+ * All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sub license, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
+ * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+ * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+ * USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) shall be included in all copies or substantial portions
+ * of the Software.
+ *
+ */
+/*
+ * Authors:
+ *    Christian König <christian.koenig@amd.com>
+ */
+
+#include <linux/firmware.h>
+#include <linux/module.h>
+#include <linux/mmu_notifier.h>
+#include <drm/drmP.h>
+#include <drm/drm.h>
+
+#include "amdgpu.h"
+
+struct amdgpu_mn {
+	/* constant after initialisation */
+	struct amdgpu_device	*adev;
+	struct mm_struct	*mm;
+	struct mmu_notifier	mn;
+
+	/* only used on destruction */
+	struct work_struct	work;
+
+	/* protected by adev->mn_lock */
+	struct hlist_node	node;
+
+	/* objects protected by lock */
+	struct mutex		lock;
+	struct rb_root		objects;
+};
+
+struct amdgpu_mn_node {
+	struct interval_tree_node	it;
+	struct list_head		bos;
+};
+
+/**
+ * amdgpu_mn_destroy - destroy the rmn
+ *
+ * @work: previously sheduled work item
+ *
+ * Lazy destroys the notifier from a work item
+ */
+static void amdgpu_mn_destroy(struct work_struct *work)
+{
+	struct amdgpu_mn *rmn = container_of(work, struct amdgpu_mn, work);
+	struct amdgpu_device *adev = rmn->adev;
+	struct amdgpu_mn_node *node, *next_node;
+	struct amdgpu_bo *bo, *next_bo;
+
+	mutex_lock(&adev->mn_lock);
+	mutex_lock(&rmn->lock);
+	hash_del(&rmn->node);
+	rbtree_postorder_for_each_entry_safe(node, next_node, &rmn->objects,
+					     it.rb) {
+
+		interval_tree_remove(&node->it, &rmn->objects);
+		list_for_each_entry_safe(bo, next_bo, &node->bos, mn_list) {
+			bo->mn = NULL;
+			list_del_init(&bo->mn_list);
+		}
+		kfree(node);
+	}
+	mutex_unlock(&rmn->lock);
+	mutex_unlock(&adev->mn_lock);
+	mmu_notifier_unregister(&rmn->mn, rmn->mm);
+	kfree(rmn);
+}
+
+/**
+ * amdgpu_mn_release - callback to notify about mm destruction
+ *
+ * @mn: our notifier
+ * @mn: the mm this callback is about
+ *
+ * Shedule a work item to lazy destroy our notifier.
+ */
+static void amdgpu_mn_release(struct mmu_notifier *mn,
+			      struct mm_struct *mm)
+{
+	struct amdgpu_mn *rmn = container_of(mn, struct amdgpu_mn, mn);
+	INIT_WORK(&rmn->work, amdgpu_mn_destroy);
+	schedule_work(&rmn->work);
+}
+
+/**
+ * amdgpu_mn_invalidate_range_start - callback to notify about mm change
+ *
+ * @mn: our notifier
+ * @mn: the mm this callback is about
+ * @start: start of updated range
+ * @end: end of updated range
+ *
+ * We block for all BOs between start and end to be idle and
+ * unmap them by move them into system domain again.
+ */
+static void amdgpu_mn_invalidate_range_start(struct mmu_notifier *mn,
+					     struct mm_struct *mm,
+					     unsigned long start,
+					     unsigned long end)
+{
+	struct amdgpu_mn *rmn = container_of(mn, struct amdgpu_mn, mn);
+	struct interval_tree_node *it;
+
+	/* notification is exclusive, but interval is inclusive */
+	end -= 1;
+
+	mutex_lock(&rmn->lock);
+
+	it = interval_tree_iter_first(&rmn->objects, start, end);
+	while (it) {
+		struct amdgpu_mn_node *node;
+		struct amdgpu_bo *bo;
+		int r;
+
+		node = container_of(it, struct amdgpu_mn_node, it);
+		it = interval_tree_iter_next(it, start, end);
+
+		list_for_each_entry(bo, &node->bos, mn_list) {
+
+			r = amdgpu_bo_reserve(bo, true);
+			if (r) {
+				DRM_ERROR("(%d) failed to reserve user bo\n", r);
+				continue;
+			}
+
+			r = reservation_object_wait_timeout_rcu(bo->tbo.resv,
+				true, false, MAX_SCHEDULE_TIMEOUT);
+			if (r)
+				DRM_ERROR("(%d) failed to wait for user bo\n", r);
+
+			amdgpu_ttm_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_CPU);
+			r = ttm_bo_validate(&bo->tbo, &bo->placement, false, false);
+			if (r)
+				DRM_ERROR("(%d) failed to validate user bo\n", r);
+
+			amdgpu_bo_unreserve(bo);
+		}
+	}
+
+	mutex_unlock(&rmn->lock);
+}
+
+static const struct mmu_notifier_ops amdgpu_mn_ops = {
+	.release = amdgpu_mn_release,
+	.invalidate_range_start = amdgpu_mn_invalidate_range_start,
+};
+
+/**
+ * amdgpu_mn_get - create notifier context
+ *
+ * @adev: amdgpu device pointer
+ *
+ * Creates a notifier context for current->mm.
+ */
+static struct amdgpu_mn *amdgpu_mn_get(struct amdgpu_device *adev)
+{
+	struct mm_struct *mm = current->mm;
+	struct amdgpu_mn *rmn;
+	int r;
+
+	down_write(&mm->mmap_sem);
+	mutex_lock(&adev->mn_lock);
+
+	hash_for_each_possible(adev->mn_hash, rmn, node, (unsigned long)mm)
+		if (rmn->mm == mm)
+			goto release_locks;
+
+	rmn = kzalloc(sizeof(*rmn), GFP_KERNEL);
+	if (!rmn) {
+		rmn = ERR_PTR(-ENOMEM);
+		goto release_locks;
+	}
+
+	rmn->adev = adev;
+	rmn->mm = mm;
+	rmn->mn.ops = &amdgpu_mn_ops;
+	mutex_init(&rmn->lock);
+	rmn->objects = RB_ROOT;
+
+	r = __mmu_notifier_register(&rmn->mn, mm);
+	if (r)
+		goto free_rmn;
+
+	hash_add(adev->mn_hash, &rmn->node, (unsigned long)mm);
+
+release_locks:
+	mutex_unlock(&adev->mn_lock);
+	up_write(&mm->mmap_sem);
+
+	return rmn;
+
+free_rmn:
+	mutex_unlock(&adev->mn_lock);
+	up_write(&mm->mmap_sem);
+	kfree(rmn);
+
+	return ERR_PTR(r);
+}
+
+/**
+ * amdgpu_mn_register - register a BO for notifier updates
+ *
+ * @bo: amdgpu buffer object
+ * @addr: userptr addr we should monitor
+ *
+ * Registers an MMU notifier for the given BO at the specified address.
+ * Returns 0 on success, -ERRNO if anything goes wrong.
+ */
+int amdgpu_mn_register(struct amdgpu_bo *bo, unsigned long addr)
+{
+	unsigned long end = addr + amdgpu_bo_size(bo) - 1;
+	struct amdgpu_device *adev = bo->adev;
+	struct amdgpu_mn *rmn;
+	struct amdgpu_mn_node *node = NULL;
+	struct list_head bos;
+	struct interval_tree_node *it;
+
+	rmn = amdgpu_mn_get(adev);
+	if (IS_ERR(rmn))
+		return PTR_ERR(rmn);
+
+	INIT_LIST_HEAD(&bos);
+
+	mutex_lock(&rmn->lock);
+
+	while ((it = interval_tree_iter_first(&rmn->objects, addr, end))) {
+		kfree(node);
+		node = container_of(it, struct amdgpu_mn_node, it);
+		interval_tree_remove(&node->it, &rmn->objects);
+		addr = min(it->start, addr);
+		end = max(it->last, end);
+		list_splice(&node->bos, &bos);
+	}
+
+	if (!node) {
+		node = kmalloc(sizeof(struct amdgpu_mn_node), GFP_KERNEL);
+		if (!node) {
+			mutex_unlock(&rmn->lock);
+			return -ENOMEM;
+		}
+	}
+
+	bo->mn = rmn;
+
+	node->it.start = addr;
+	node->it.last = end;
+	INIT_LIST_HEAD(&node->bos);
+	list_splice(&bos, &node->bos);
+	list_add(&bo->mn_list, &node->bos);
+
+	interval_tree_insert(&node->it, &rmn->objects);
+
+	mutex_unlock(&rmn->lock);
+
+	return 0;
+}
+
+/**
+ * amdgpu_mn_unregister - unregister a BO for notifier updates
+ *
+ * @bo: amdgpu buffer object
+ *
+ * Remove any registration of MMU notifier updates from the buffer object.
+ */
+void amdgpu_mn_unregister(struct amdgpu_bo *bo)
+{
+	struct amdgpu_device *adev = bo->adev;
+	struct amdgpu_mn *rmn;
+	struct list_head *head;
+
+	mutex_lock(&adev->mn_lock);
+	rmn = bo->mn;
+	if (rmn == NULL) {
+		mutex_unlock(&adev->mn_lock);
+		return;
+	}
+
+	mutex_lock(&rmn->lock);
+	/* save the next list entry for later */
+	head = bo->mn_list.next;
+
+	bo->mn = NULL;
+	list_del(&bo->mn_list);
+
+	if (list_empty(head)) {
+		struct amdgpu_mn_node *node;
+		node = container_of(head, struct amdgpu_mn_node, bos);
+		interval_tree_remove(&node->it, &rmn->objects);
+		kfree(node);
+	}
+
+	mutex_unlock(&rmn->lock);
+	mutex_unlock(&adev->mn_lock);
+}