drm/vmwgfx: Introduce a new placement for MOB page tables

For larger (bigger than a page) and noncontiguous mobs we have
to create page tables that allow the host to find the memory.
Those page tables just used regular system memory. Unfortunately
in TTM those BO's are not allowed to be busy thus can't be
fenced and we have to fence those bo's  because we don't want
to destroy the page tables while the host is still executing
the command buffers which might be accessing them.

To solve it we introduce a new placement VMW_PL_SYSTEM which
is very similar to TTM_PL_SYSTEM except that it allows
fencing. This fixes kernel oops'es during unloading of the driver
(and pci hot remove/add) which were caused by busy BO's in
TTM_PL_SYSTEM being present in the delayed deletion list in
TTM (TTM_PL_SYSTEM manager is destroyed before the delayed
deletions are executed)

Signed-off-by: Zack Rusin <zackr@vmware.com>
Reviewed-by: Martin Krastev <krastevm@vmware.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211105193845.258816-5-zackr@vmware.com

1 files changed, 90 insertions, 0 deletions

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_system_manager.c b/drivers/gpu/drm/vmwgfx/vmwgfx_system_manager.c
new file mode 100644
index 000000000000..b0005b03a617
--- /dev/null
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_system_manager.c
@@ -0,0 +1,90 @@
+/* SPDX-License-Identifier: GPL-2.0 OR MIT */
+/*
+ * Copyright 2021 VMware, Inc.
+ *
+ * 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, sublicense, 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 above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * 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
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * 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.
+ *
+ */
+
+#include "vmwgfx_drv.h"
+
+#include <drm/ttm/ttm_bo_driver.h>
+#include <drm/ttm/ttm_device.h>
+#include <drm/ttm/ttm_placement.h>
+#include <drm/ttm/ttm_resource.h>
+#include <linux/slab.h>
+
+
+static int vmw_sys_man_alloc(struct ttm_resource_manager *man,
+			     struct ttm_buffer_object *bo,
+			     const struct ttm_place *place,
+			     struct ttm_resource **res)
+{
+	*res = kzalloc(sizeof(**res), GFP_KERNEL);
+	if (!*res)
+		return -ENOMEM;
+
+	ttm_resource_init(bo, place, *res);
+	return 0;
+}
+
+static void vmw_sys_man_free(struct ttm_resource_manager *man,
+			     struct ttm_resource *res)
+{
+	kfree(res);
+}
+
+static const struct ttm_resource_manager_func vmw_sys_manager_func = {
+	.alloc = vmw_sys_man_alloc,
+	.free = vmw_sys_man_free,
+};
+
+int vmw_sys_man_init(struct vmw_private *dev_priv)
+{
+	struct ttm_device *bdev = &dev_priv->bdev;
+	struct ttm_resource_manager *man =
+			kzalloc(sizeof(*man), GFP_KERNEL);
+
+	if (!man)
+		return -ENOMEM;
+
+	man->use_tt = true;
+	man->func = &vmw_sys_manager_func;
+
+	ttm_resource_manager_init(man, 0);
+	ttm_set_driver_manager(bdev, VMW_PL_SYSTEM, man);
+	ttm_resource_manager_set_used(man, true);
+	return 0;
+}
+
+void vmw_sys_man_fini(struct vmw_private *dev_priv)
+{
+	struct ttm_resource_manager *man = ttm_manager_type(&dev_priv->bdev,
+							    VMW_PL_SYSTEM);
+
+	ttm_resource_manager_evict_all(&dev_priv->bdev, man);
+
+	ttm_resource_manager_set_used(man, false);
+	ttm_resource_manager_cleanup(man);
+
+	ttm_set_driver_manager(&dev_priv->bdev, VMW_PL_SYSTEM, NULL);
+	kfree(man);
+}