1/*
  2 * Copyright (C) 2015 Red Hat, Inc.
  3 * All Rights Reserved.
  4 *
  5 * Authors:
  6 *    Dave Airlie
  7 *    Alon Levy
  8 *
  9 * Permission is hereby granted, free of charge, to any person obtaining a
 10 * copy of this software and associated documentation files (the "Software"),
 11 * to deal in the Software without restriction, including without limitation
 12 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 13 * and/or sell copies of the Software, and to permit persons to whom the
 14 * Software is furnished to do so, subject to the following conditions:
 15 *
 16 * The above copyright notice and this permission notice shall be included in
 17 * all copies or substantial portions of the Software.
 18 *
 19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 20 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 21 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 22 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
 23 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 24 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 25 * OTHER DEALINGS IN THE SOFTWARE.
 26 */
 27
 28#include <ttm/ttm_bo_api.h>
 29#include <ttm/ttm_bo_driver.h>
 30#include <ttm/ttm_placement.h>
 31#include <ttm/ttm_page_alloc.h>
 32#include <ttm/ttm_module.h>
 33#include <drm/drmP.h>
 34#include <drm/drm.h>
 35#include <drm/virtgpu_drm.h>
 36#include "virtgpu_drv.h"
 37
 38#include <linux/delay.h>
 39
 40#define DRM_FILE_PAGE_OFFSET (0x100000000ULL >> PAGE_SHIFT)
 41
 42static struct
 43virtio_gpu_device *virtio_gpu_get_vgdev(struct ttm_bo_device *bdev)
 44{
 45	struct virtio_gpu_mman *mman;
 46	struct virtio_gpu_device *vgdev;
 47
 48	mman = container_of(bdev, struct virtio_gpu_mman, bdev);
 49	vgdev = container_of(mman, struct virtio_gpu_device, mman);
 50	return vgdev;
 51}
 52
 53static int virtio_gpu_ttm_mem_global_init(struct drm_global_reference *ref)
 54{
 55	return ttm_mem_global_init(ref->object);
 56}
 57
 58static void virtio_gpu_ttm_mem_global_release(struct drm_global_reference *ref)
 59{
 60	ttm_mem_global_release(ref->object);
 61}
 62
 63static int virtio_gpu_ttm_global_init(struct virtio_gpu_device *vgdev)
 64{
 65	struct drm_global_reference *global_ref;
 66	int r;
 67
 68	vgdev->mman.mem_global_referenced = false;
 69	global_ref = &vgdev->mman.mem_global_ref;
 70	global_ref->global_type = DRM_GLOBAL_TTM_MEM;
 71	global_ref->size = sizeof(struct ttm_mem_global);
 72	global_ref->init = &virtio_gpu_ttm_mem_global_init;
 73	global_ref->release = &virtio_gpu_ttm_mem_global_release;
 74
 75	r = drm_global_item_ref(global_ref);
 76	if (r != 0) {
 77		DRM_ERROR("Failed setting up TTM memory accounting "
 78			  "subsystem.\n");
 79		return r;
 80	}
 81
 82	vgdev->mman.bo_global_ref.mem_glob =
 83		vgdev->mman.mem_global_ref.object;
 84	global_ref = &vgdev->mman.bo_global_ref.ref;
 85	global_ref->global_type = DRM_GLOBAL_TTM_BO;
 86	global_ref->size = sizeof(struct ttm_bo_global);
 87	global_ref->init = &ttm_bo_global_init;
 88	global_ref->release = &ttm_bo_global_release;
 89	r = drm_global_item_ref(global_ref);
 90	if (r != 0) {
 91		DRM_ERROR("Failed setting up TTM BO subsystem.\n");
 92		drm_global_item_unref(&vgdev->mman.mem_global_ref);
 93		return r;
 94	}
 95
 96	vgdev->mman.mem_global_referenced = true;
 97	return 0;
 98}
 99
100static void virtio_gpu_ttm_global_fini(struct virtio_gpu_device *vgdev)
101{
102	if (vgdev->mman.mem_global_referenced) {
103		drm_global_item_unref(&vgdev->mman.bo_global_ref.ref);
104		drm_global_item_unref(&vgdev->mman.mem_global_ref);
105		vgdev->mman.mem_global_referenced = false;
106	}
107}
108
109#if 0
110/*
111 * Hmm, seems to not do anything useful.  Leftover debug hack?
112 * Something like printing pagefaults to kernel log?
113 */
114static struct vm_operations_struct virtio_gpu_ttm_vm_ops;
115static const struct vm_operations_struct *ttm_vm_ops;
116
117static int virtio_gpu_ttm_fault(struct vm_area_struct *vma,
118				struct vm_fault *vmf)
119{
120	struct ttm_buffer_object *bo;
121	struct virtio_gpu_device *vgdev;
122	int r;
123
124	bo = (struct ttm_buffer_object *)vma->vm_private_data;
125	if (bo == NULL)
126		return VM_FAULT_NOPAGE;
127	vgdev = virtio_gpu_get_vgdev(bo->bdev);
128	r = ttm_vm_ops->fault(vma, vmf);
129	return r;
130}
131#endif
132
133int virtio_gpu_mmap(struct file *filp, struct vm_area_struct *vma)
134{
135	struct drm_file *file_priv;
136	struct virtio_gpu_device *vgdev;
137	int r;
138
139	file_priv = filp->private_data;
140	vgdev = file_priv->minor->dev->dev_private;
141	if (vgdev == NULL) {
142		DRM_ERROR(
143		 "filp->private_data->minor->dev->dev_private == NULL\n");
144		return -EINVAL;
145	}
146	r = ttm_bo_mmap(filp, vma, &vgdev->mman.bdev);
147#if 0
148	if (unlikely(r != 0))
149		return r;
150	if (unlikely(ttm_vm_ops == NULL)) {
151		ttm_vm_ops = vma->vm_ops;
152		virtio_gpu_ttm_vm_ops = *ttm_vm_ops;
153		virtio_gpu_ttm_vm_ops.fault = &virtio_gpu_ttm_fault;
154	}
155	vma->vm_ops = &virtio_gpu_ttm_vm_ops;
156	return 0;
157#else
158	return r;
159#endif
160}
161
162static int virtio_gpu_invalidate_caches(struct ttm_bo_device *bdev,
163					uint32_t flags)
164{
165	return 0;
166}
167
168static int ttm_bo_man_get_node(struct ttm_mem_type_manager *man,
169			       struct ttm_buffer_object *bo,
170			       const struct ttm_place *place,
171			       struct ttm_mem_reg *mem)
172{
173	mem->mm_node = (void *)1;
174	return 0;
175}
176
177static void ttm_bo_man_put_node(struct ttm_mem_type_manager *man,
178				struct ttm_mem_reg *mem)
179{
180	mem->mm_node = (void *)NULL;
181	return;
182}
183
184static int ttm_bo_man_init(struct ttm_mem_type_manager *man,
185			   unsigned long p_size)
186{
187	return 0;
188}
189
190static int ttm_bo_man_takedown(struct ttm_mem_type_manager *man)
191{
192	return 0;
193}
194
195static void ttm_bo_man_debug(struct ttm_mem_type_manager *man,
196			     const char *prefix)
197{
198}
199
200static const struct ttm_mem_type_manager_func virtio_gpu_bo_manager_func = {
201	ttm_bo_man_init,
202	ttm_bo_man_takedown,
203	ttm_bo_man_get_node,
204	ttm_bo_man_put_node,
205	ttm_bo_man_debug
206};
207
208static int virtio_gpu_init_mem_type(struct ttm_bo_device *bdev, uint32_t type,
209				    struct ttm_mem_type_manager *man)
210{
211	struct virtio_gpu_device *vgdev;
212
213	vgdev = virtio_gpu_get_vgdev(bdev);
214
215	switch (type) {
216	case TTM_PL_SYSTEM:
217		/* System memory */
218		man->flags = TTM_MEMTYPE_FLAG_MAPPABLE;
219		man->available_caching = TTM_PL_MASK_CACHING;
220		man->default_caching = TTM_PL_FLAG_CACHED;
221		break;
222	case TTM_PL_TT:
223		man->func = &virtio_gpu_bo_manager_func;
224		man->flags = TTM_MEMTYPE_FLAG_MAPPABLE;
225		man->available_caching = TTM_PL_MASK_CACHING;
226		man->default_caching = TTM_PL_FLAG_CACHED;
227		break;
228	default:
229		DRM_ERROR("Unsupported memory type %u\n", (unsigned)type);
230		return -EINVAL;
231	}
232	return 0;
233}
234
235static void virtio_gpu_evict_flags(struct ttm_buffer_object *bo,
236				struct ttm_placement *placement)
237{
238	static struct ttm_place placements = {
239		.fpfn  = 0,
240		.lpfn  = 0,
241		.flags = TTM_PL_MASK_CACHING | TTM_PL_FLAG_SYSTEM,
242	};
243
244	placement->placement = &placements;
245	placement->busy_placement = &placements;
246	placement->num_placement = 1;
247	placement->num_busy_placement = 1;
248	return;
249}
250
251static int virtio_gpu_verify_access(struct ttm_buffer_object *bo,
252				    struct file *filp)
253{
254	return 0;
255}
256
257static int virtio_gpu_ttm_io_mem_reserve(struct ttm_bo_device *bdev,
258					 struct ttm_mem_reg *mem)
259{
260	struct ttm_mem_type_manager *man = &bdev->man[mem->mem_type];
261
262	mem->bus.addr = NULL;
263	mem->bus.offset = 0;
264	mem->bus.size = mem->num_pages << PAGE_SHIFT;
265	mem->bus.base = 0;
266	mem->bus.is_iomem = false;
267	if (!(man->flags & TTM_MEMTYPE_FLAG_MAPPABLE))
268		return -EINVAL;
269	switch (mem->mem_type) {
270	case TTM_PL_SYSTEM:
271	case TTM_PL_TT:
272		/* system memory */
273		return 0;
274	default:
275		return -EINVAL;
276	}
277	return 0;
278}
279
280static void virtio_gpu_ttm_io_mem_free(struct ttm_bo_device *bdev,
281				       struct ttm_mem_reg *mem)
282{
283}
284
285/*
286 * TTM backend functions.
287 */
288struct virtio_gpu_ttm_tt {
289	struct ttm_dma_tt		ttm;
290	struct virtio_gpu_device	*vgdev;
291	u64				offset;
292};
293
294static int virtio_gpu_ttm_backend_bind(struct ttm_tt *ttm,
295				       struct ttm_mem_reg *bo_mem)
296{
297	struct virtio_gpu_ttm_tt *gtt = (void *)ttm;
298
299	gtt->offset = (unsigned long)(bo_mem->start << PAGE_SHIFT);
300	if (!ttm->num_pages)
301		WARN(1, "nothing to bind %lu pages for mreg %p back %p!\n",
302		     ttm->num_pages, bo_mem, ttm);
303
304	/* Not implemented */
305	return 0;
306}
307
308static int virtio_gpu_ttm_backend_unbind(struct ttm_tt *ttm)
309{
310	/* Not implemented */
311	return 0;
312}
313
314static void virtio_gpu_ttm_backend_destroy(struct ttm_tt *ttm)
315{
316	struct virtio_gpu_ttm_tt *gtt = (void *)ttm;
317
318	ttm_dma_tt_fini(&gtt->ttm);
319	kfree(gtt);
320}
321
322static struct ttm_backend_func virtio_gpu_backend_func = {
323	.bind = &virtio_gpu_ttm_backend_bind,
324	.unbind = &virtio_gpu_ttm_backend_unbind,
325	.destroy = &virtio_gpu_ttm_backend_destroy,
326};
327
328static int virtio_gpu_ttm_tt_populate(struct ttm_tt *ttm)
329{
330	if (ttm->state != tt_unpopulated)
331		return 0;
332
333	return ttm_pool_populate(ttm);
334}
335
336static void virtio_gpu_ttm_tt_unpopulate(struct ttm_tt *ttm)
337{
338	ttm_pool_unpopulate(ttm);
339}
340
341static struct ttm_tt *virtio_gpu_ttm_tt_create(struct ttm_bo_device *bdev,
342					       unsigned long size,
343					       uint32_t page_flags,
344					       struct page *dummy_read_page)
345{
346	struct virtio_gpu_device *vgdev;
347	struct virtio_gpu_ttm_tt *gtt;
348
349	vgdev = virtio_gpu_get_vgdev(bdev);
350	gtt = kzalloc(sizeof(struct virtio_gpu_ttm_tt), GFP_KERNEL);
351	if (gtt == NULL)
352		return NULL;
353	gtt->ttm.ttm.func = &virtio_gpu_backend_func;
354	gtt->vgdev = vgdev;
355	if (ttm_dma_tt_init(&gtt->ttm, bdev, size, page_flags,
356			    dummy_read_page)) {
357		kfree(gtt);
358		return NULL;
359	}
360	return &gtt->ttm.ttm;
361}
362
363static void virtio_gpu_move_null(struct ttm_buffer_object *bo,
364				 struct ttm_mem_reg *new_mem)
365{
366	struct ttm_mem_reg *old_mem = &bo->mem;
367
368	BUG_ON(old_mem->mm_node != NULL);
369	*old_mem = *new_mem;
370	new_mem->mm_node = NULL;
371}
372
373static int virtio_gpu_bo_move(struct ttm_buffer_object *bo,
374			      bool evict, bool interruptible,
375			      bool no_wait_gpu,
376			      struct ttm_mem_reg *new_mem)
377{
378	virtio_gpu_move_null(bo, new_mem);
379	return 0;
380}
381
382static void virtio_gpu_bo_move_notify(struct ttm_buffer_object *tbo,
383				      struct ttm_mem_reg *new_mem)
384{
385	struct virtio_gpu_object *bo;
386	struct virtio_gpu_device *vgdev;
387
388	bo = container_of(tbo, struct virtio_gpu_object, tbo);
389	vgdev = (struct virtio_gpu_device *)bo->gem_base.dev->dev_private;
390
391	if (!new_mem || (new_mem->placement & TTM_PL_FLAG_SYSTEM)) {
392		if (bo->hw_res_handle)
393			virtio_gpu_cmd_resource_inval_backing(vgdev,
394							   bo->hw_res_handle);
395
396	} else if (new_mem->placement & TTM_PL_FLAG_TT) {
397		if (bo->hw_res_handle) {
398			virtio_gpu_object_attach(vgdev, bo, bo->hw_res_handle,
399						 NULL);
400		}
401	}
402}
403
404static void virtio_gpu_bo_swap_notify(struct ttm_buffer_object *tbo)
405{
406	struct virtio_gpu_object *bo;
407	struct virtio_gpu_device *vgdev;
408
409	bo = container_of(tbo, struct virtio_gpu_object, tbo);
410	vgdev = (struct virtio_gpu_device *)bo->gem_base.dev->dev_private;
411
412	if (bo->pages)
413		virtio_gpu_object_free_sg_table(bo);
414}
415
416static struct ttm_bo_driver virtio_gpu_bo_driver = {
417	.ttm_tt_create = &virtio_gpu_ttm_tt_create,
418	.ttm_tt_populate = &virtio_gpu_ttm_tt_populate,
419	.ttm_tt_unpopulate = &virtio_gpu_ttm_tt_unpopulate,
420	.invalidate_caches = &virtio_gpu_invalidate_caches,
421	.init_mem_type = &virtio_gpu_init_mem_type,
422	.evict_flags = &virtio_gpu_evict_flags,
423	.move = &virtio_gpu_bo_move,
424	.verify_access = &virtio_gpu_verify_access,
425	.io_mem_reserve = &virtio_gpu_ttm_io_mem_reserve,
426	.io_mem_free = &virtio_gpu_ttm_io_mem_free,
427	.move_notify = &virtio_gpu_bo_move_notify,
428	.swap_notify = &virtio_gpu_bo_swap_notify,
429};
430
431int virtio_gpu_ttm_init(struct virtio_gpu_device *vgdev)
432{
433	int r;
434
435	r = virtio_gpu_ttm_global_init(vgdev);
436	if (r)
437		return r;
438	/* No others user of address space so set it to 0 */
439	r = ttm_bo_device_init(&vgdev->mman.bdev,
440			       vgdev->mman.bo_global_ref.ref.object,
441			       &virtio_gpu_bo_driver,
442			       vgdev->ddev->anon_inode->i_mapping,
443			       DRM_FILE_PAGE_OFFSET, 0);
444	if (r) {
445		DRM_ERROR("failed initializing buffer object driver(%d).\n", r);
446		goto err_dev_init;
447	}
448
449	r = ttm_bo_init_mm(&vgdev->mman.bdev, TTM_PL_TT, 0);
450	if (r) {
451		DRM_ERROR("Failed initializing GTT heap.\n");
452		goto err_mm_init;
453	}
454	return 0;
455
456err_mm_init:
457	ttm_bo_device_release(&vgdev->mman.bdev);
458err_dev_init:
459	virtio_gpu_ttm_global_fini(vgdev);
460	return r;
461}
462
463void virtio_gpu_ttm_fini(struct virtio_gpu_device *vgdev)
464{
465	ttm_bo_device_release(&vgdev->mman.bdev);
466	virtio_gpu_ttm_global_fini(vgdev);
467	DRM_INFO("virtio_gpu: ttm finalized\n");
468}