drm/amdgpu: fix the issue of reserving bad pages failed

In amdgpu_ras_reset_gpu, because bad pages may not be freed,
it has high probability to reserve bad pages failed.

Change to reserve bad pages when freeing VRAM.

v2:
1. avoid allocating the drm_mm node outside of amdgpu_vram_mgr.c
2. move bad page reserving into amdgpu_ras_add_bad_pages, if vram mgr
   reserve bad page failed, it will put it into pending list, otherwise
   put it into processed list;
3. remove amdgpu_ras_release_bad_pages, because retired page's info has
   been moved into amdgpu_vram_mgr

v3:
1. formate code style;
2. rename amdgpu_vram_reserve_scope as amdgpu_vram_reservation;
3. rename scope_pending as reservations_pending;
4. rename scope_processed as reserved_pages;
5. change to iterate over all the pending ones and try to insert them
   with drm_mm_reserve_node();

v4:
1. rename amdgpu_vram_mgr_reserve_scope as
amdgpu_vram_mgr_reserve_range;
2. remove unused include "amdgpu_ras.h";
3. rename amdgpu_vram_mgr_check_and_reserve as
amdgpu_vram_mgr_do_reserve;
4. refine amdgpu_vram_mgr_reserve_range to call
amdgpu_vram_mgr_do_reserve.

Reviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Hawking Zhang <hawking.zhang@amd.com>
Signed-off-by: Dennis Li <Dennis.Li@amd.com>
Signed-off-by: Wenhui Sheng <Wenhui.Sheng@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

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

@@ -187,6 +187,8 @@ int amdgpu_vram_mgr_init(struct amdgpu_device *adev)
 
 	drm_mm_init(&mgr->mm, 0, man->size);
 	spin_lock_init(&mgr->lock);
+	INIT_LIST_HEAD(&mgr->reservations_pending);
+	INIT_LIST_HEAD(&mgr->reserved_pages);
 
 	/* Add the two VRAM-related sysfs files */
 	ret = sysfs_create_files(&adev->dev->kobj, amdgpu_vram_mgr_attributes);
@@ -211,6 +213,7 @@ void amdgpu_vram_mgr_fini(struct amdgpu_device *adev)
 	struct amdgpu_vram_mgr *mgr = &adev->mman.vram_mgr;
 	struct ttm_resource_manager *man = &mgr->manager;
 	int ret;
+	struct amdgpu_vram_reservation *rsv, *temp;
 
 	ttm_resource_manager_set_used(man, false);
 
@@ -219,6 +222,13 @@ void amdgpu_vram_mgr_fini(struct amdgpu_device *adev)
 		return;
 
 	spin_lock(&mgr->lock);
+	list_for_each_entry_safe(rsv, temp, &mgr->reservations_pending, node)
+		kfree(rsv);
+
+	list_for_each_entry_safe(rsv, temp, &mgr->reserved_pages, node) {
+		drm_mm_remove_node(&rsv->mm_node);
+		kfree(rsv);
+	}
 	drm_mm_takedown(&mgr->mm);
 	spin_unlock(&mgr->lock);
 
@@ -277,6 +287,101 @@ u64 amdgpu_vram_mgr_bo_visible_size(struct amdgpu_bo *bo)
 	return usage;
 }
 
+static void amdgpu_vram_mgr_do_reserve(struct ttm_resource_manager *man)
+{
+	struct amdgpu_vram_mgr *mgr = to_vram_mgr(man);
+	struct amdgpu_device *adev = to_amdgpu_device(mgr);
+	struct drm_mm *mm = &mgr->mm;
+	struct amdgpu_vram_reservation *rsv, *temp;
+	uint64_t vis_usage;
+
+	list_for_each_entry_safe(rsv, temp, &mgr->reservations_pending, node) {
+		if (drm_mm_reserve_node(mm, &rsv->mm_node))
+			continue;
+
+		dev_dbg(adev->dev, "Reservation 0x%llx - %lld, Successed\n",
+			rsv->mm_node.start, rsv->mm_node.size);
+
+		vis_usage = amdgpu_vram_mgr_vis_size(adev, &rsv->mm_node);
+		atomic64_add(vis_usage, &mgr->vis_usage);
+		atomic64_add(rsv->mm_node.size << PAGE_SHIFT, &mgr->usage);
+		list_move(&rsv->node, &mgr->reserved_pages);
+	}
+}
+
+/**
+ * amdgpu_vram_mgr_reserve_range - Reserve a range from VRAM
+ *
+ * @man: TTM memory type manager
+ * @start: start address of the range in VRAM
+ * @size: size of the range
+ *
+ * Reserve memory from start addess with the specified size in VRAM
+ */
+int amdgpu_vram_mgr_reserve_range(struct ttm_resource_manager *man,
+				  uint64_t start, uint64_t size)
+{
+	struct amdgpu_vram_mgr *mgr = to_vram_mgr(man);
+	struct amdgpu_vram_reservation *rsv;
+
+	rsv = kzalloc(sizeof(*rsv), GFP_KERNEL);
+	if (!rsv)
+		return -ENOMEM;
+
+	INIT_LIST_HEAD(&rsv->node);
+	rsv->mm_node.start = start >> PAGE_SHIFT;
+	rsv->mm_node.size = size >> PAGE_SHIFT;
+
+	spin_lock(&mgr->lock);
+	list_add_tail(&mgr->reservations_pending, &rsv->node);
+	amdgpu_vram_mgr_do_reserve(man);
+	spin_unlock(&mgr->lock);
+
+	return 0;
+}
+
+/**
+ * amdgpu_vram_mgr_query_page_status - query the reservation status
+ *
+ * @man: TTM memory type manager
+ * @start: start address of a page in VRAM
+ *
+ * Returns:
+ *	-EBUSY: the page is still hold and in pending list
+ *	0: the page has been reserved
+ *	-ENOENT: the input page is not a reservation
+ */
+int amdgpu_vram_mgr_query_page_status(struct ttm_resource_manager *man,
+				      uint64_t start)
+{
+	struct amdgpu_vram_mgr *mgr = to_vram_mgr(man);
+	struct amdgpu_vram_reservation *rsv;
+	int ret;
+
+	spin_lock(&mgr->lock);
+
+	list_for_each_entry(rsv, &mgr->reservations_pending, node) {
+		if ((rsv->mm_node.start <= start) &&
+		    (start < (rsv->mm_node.start + rsv->mm_node.size))) {
+			ret = -EBUSY;
+			goto out;
+		}
+	}
+
+	list_for_each_entry(rsv, &mgr->reserved_pages, node) {
+		if ((rsv->mm_node.start <= start) &&
+		    (start < (rsv->mm_node.start + rsv->mm_node.size))) {
+			ret = 0;
+			goto out;
+		}
+	}
+
+	ret = -ENOENT;
+out:
+	spin_unlock(&mgr->lock);
+	return ret;
+}
+
 /**
  * amdgpu_vram_mgr_virt_start - update virtual start address
  *
@@ -447,6 +552,7 @@ static void amdgpu_vram_mgr_del(struct ttm_resource_manager *man,
 		vis_usage += amdgpu_vram_mgr_vis_size(adev, nodes);
 		++nodes;
 	}
+	amdgpu_vram_mgr_do_reserve(man);
 	spin_unlock(&mgr->lock);
 
 	atomic64_sub(usage, &mgr->usage);