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 <drm/ttm/ttm_bo_api.h>
 29#include <drm/ttm/ttm_bo_driver.h>
 30#include <drm/ttm/ttm_placement.h>
 31#include <drm/ttm/ttm_page_alloc.h>
 32#include <drm/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_fault *vmf)
118{
119	struct ttm_buffer_object *bo;
120	struct virtio_gpu_device *vgdev;
121	int r;
122
123	bo = (struct ttm_buffer_object *)vmf->vma->vm_private_data;
124	if (bo == NULL)
125		return VM_FAULT_NOPAGE;
126	vgdev = virtio_gpu_get_vgdev(bo->bdev);
127	r = ttm_vm_ops->fault(vmf);
128	return r;
129}
130#endif
131
132int virtio_gpu_mmap(struct file *filp, struct vm_area_struct *vma)
133{
134	struct drm_file *file_priv;
135	struct virtio_gpu_device *vgdev;
136	int r;
137
138	file_priv = filp->private_data;
139	vgdev = file_priv->minor->dev->dev_private;
140	if (vgdev == NULL) {
141		DRM_ERROR(
142		 "filp->private_data->minor->dev->dev_private == NULL\n");
143		return -EINVAL;
144	}
145	r = ttm_bo_mmap(filp, vma, &vgdev->mman.bdev);
146#if 0
147	if (unlikely(r != 0))
148		return r;
149	if (unlikely(ttm_vm_ops == NULL)) {
150		ttm_vm_ops = vma->vm_ops;
151		virtio_gpu_ttm_vm_ops = *ttm_vm_ops;
152		virtio_gpu_ttm_vm_ops.fault = &virtio_gpu_ttm_fault;
153	}
154	vma->vm_ops = &virtio_gpu_ttm_vm_ops;
155	return 0;
156#else
157	return r;
158#endif
159}
160
161static int virtio_gpu_invalidate_caches(struct ttm_bo_device *bdev,
162					uint32_t flags)
163{
164	return 0;
165}
166
167static int ttm_bo_man_get_node(struct ttm_mem_type_manager *man,
168			       struct ttm_buffer_object *bo,
169			       const struct ttm_place *place,
170			       struct ttm_mem_reg *mem)
171{
172	mem->mm_node = (void *)1;
173	return 0;
174}
175
176static void ttm_bo_man_put_node(struct ttm_mem_type_manager *man,
177				struct ttm_mem_reg *mem)
178{
179	mem->mm_node = (void *)NULL;
180}
181
182static int ttm_bo_man_init(struct ttm_mem_type_manager *man,
183			   unsigned long p_size)
184{
185	return 0;
186}
187
188static int ttm_bo_man_takedown(struct ttm_mem_type_manager *man)
189{
190	return 0;
191}
192
193static void ttm_bo_man_debug(struct ttm_mem_type_manager *man,
194			     struct drm_printer *printer)
195{
196}
197
198static const struct ttm_mem_type_manager_func virtio_gpu_bo_manager_func = {
199	.init = ttm_bo_man_init,
200	.takedown = ttm_bo_man_takedown,
201	.get_node = ttm_bo_man_get_node,
202	.put_node = ttm_bo_man_put_node,
203	.debug = ttm_bo_man_debug
204};
205
206static int virtio_gpu_init_mem_type(struct ttm_bo_device *bdev, uint32_t type,
207				    struct ttm_mem_type_manager *man)
208{
209	struct virtio_gpu_device *vgdev;
210
211	vgdev = virtio_gpu_get_vgdev(bdev);
212
213	switch (type) {
214	case TTM_PL_SYSTEM:
215		/* System memory */
216		man->flags = TTM_MEMTYPE_FLAG_MAPPABLE;
217		man->available_caching = TTM_PL_MASK_CACHING;
218		man->default_caching = TTM_PL_FLAG_CACHED;
219		break;
220	case TTM_PL_TT:
221		man->func = &virtio_gpu_bo_manager_func;
222		man->flags = TTM_MEMTYPE_FLAG_MAPPABLE;
223		man->available_caching = TTM_PL_MASK_CACHING;
224		man->default_caching = TTM_PL_FLAG_CACHED;
225		break;
226	default:
227		DRM_ERROR("Unsupported memory type %u\n", (unsigned int)type);
228		return -EINVAL;
229	}
230	return 0;
231}
232
233static void virtio_gpu_evict_flags(struct ttm_buffer_object *bo,
234				struct ttm_placement *placement)
235{
236	static const struct ttm_place placements = {
237		.fpfn  = 0,
238		.lpfn  = 0,
239		.flags = TTM_PL_MASK_CACHING | TTM_PL_FLAG_SYSTEM,
240	};
241
242	placement->placement = &placements;
243	placement->busy_placement = &placements;
244	placement->num_placement = 1;
245	placement->num_busy_placement = 1;
246}
247
248static int virtio_gpu_verify_access(struct ttm_buffer_object *bo,
249				    struct file *filp)
250{
251	return 0;
252}
253
254static int virtio_gpu_ttm_io_mem_reserve(struct ttm_bo_device *bdev,
255					 struct ttm_mem_reg *mem)
256{
257	struct ttm_mem_type_manager *man = &bdev->man[mem->mem_type];
258
259	mem->bus.addr = NULL;
260	mem->bus.offset = 0;
261	mem->bus.size = mem->num_pages << PAGE_SHIFT;
262	mem->bus.base = 0;
263	mem->bus.is_iomem = false;
264	if (!(man->flags & TTM_MEMTYPE_FLAG_MAPPABLE))
265		return -EINVAL;
266	switch (mem->mem_type) {
267	case TTM_PL_SYSTEM:
268	case TTM_PL_TT:
269		/* system memory */
270		return 0;
271	default:
272		return -EINVAL;
273	}
274	return 0;
275}
276
277static void virtio_gpu_ttm_io_mem_free(struct ttm_bo_device *bdev,
278				       struct ttm_mem_reg *mem)
279{
280}
281
282/*
283 * TTM backend functions.
284 */
285struct virtio_gpu_ttm_tt {
286	struct ttm_dma_tt		ttm;
287	struct virtio_gpu_device	*vgdev;
288	u64				offset;
289};
290
291static int virtio_gpu_ttm_backend_bind(struct ttm_tt *ttm,
292				       struct ttm_mem_reg *bo_mem)
293{
294	struct virtio_gpu_ttm_tt *gtt = (void *)ttm;
295
296	gtt->offset = (unsigned long)(bo_mem->start << PAGE_SHIFT);
297	if (!ttm->num_pages)
298		WARN(1, "nothing to bind %lu pages for mreg %p back %p!\n",
299		     ttm->num_pages, bo_mem, ttm);
300
301	/* Not implemented */
302	return 0;
303}
304
305static int virtio_gpu_ttm_backend_unbind(struct ttm_tt *ttm)
306{
307	/* Not implemented */
308	return 0;
309}
310
311static void virtio_gpu_ttm_backend_destroy(struct ttm_tt *ttm)
312{
313	struct virtio_gpu_ttm_tt *gtt = (void *)ttm;
314
315	ttm_dma_tt_fini(&gtt->ttm);
316	kfree(gtt);
317}
318
319static struct ttm_backend_func virtio_gpu_backend_func = {
320	.bind = &virtio_gpu_ttm_backend_bind,
321	.unbind = &virtio_gpu_ttm_backend_unbind,
322	.destroy = &virtio_gpu_ttm_backend_destroy,
323};
324
325static struct ttm_tt *virtio_gpu_ttm_tt_create(struct ttm_buffer_object *bo,
326					       uint32_t page_flags)
327{
328	struct virtio_gpu_device *vgdev;
329	struct virtio_gpu_ttm_tt *gtt;
330
331	vgdev = virtio_gpu_get_vgdev(bo->bdev);
332	gtt = kzalloc(sizeof(struct virtio_gpu_ttm_tt), GFP_KERNEL);
333	if (gtt == NULL)
334		return NULL;
335	gtt->ttm.ttm.func = &virtio_gpu_backend_func;
336	gtt->vgdev = vgdev;
337	if (ttm_dma_tt_init(&gtt->ttm, bo, page_flags)) {
338		kfree(gtt);
339		return NULL;
340	}
341	return &gtt->ttm.ttm;
342}
343
344static void virtio_gpu_move_null(struct ttm_buffer_object *bo,
345				 struct ttm_mem_reg *new_mem)
346{
347	struct ttm_mem_reg *old_mem = &bo->mem;
348
349	BUG_ON(old_mem->mm_node != NULL);
350	*old_mem = *new_mem;
351	new_mem->mm_node = NULL;
352}
353
354static int virtio_gpu_bo_move(struct ttm_buffer_object *bo, bool evict,
355			      struct ttm_operation_ctx *ctx,
356			      struct ttm_mem_reg *new_mem)
357{
358	int ret;
359
360	ret = ttm_bo_wait(bo, ctx->interruptible, ctx->no_wait_gpu);
361	if (ret)
362		return ret;
363
364	virtio_gpu_move_null(bo, new_mem);
365	return 0;
366}
367
368static void virtio_gpu_bo_move_notify(struct ttm_buffer_object *tbo,
369				      bool evict,
370				      struct ttm_mem_reg *new_mem)
371{
372	struct virtio_gpu_object *bo;
373	struct virtio_gpu_device *vgdev;
374
375	bo = container_of(tbo, struct virtio_gpu_object, tbo);
376	vgdev = (struct virtio_gpu_device *)bo->gem_base.dev->dev_private;
377
378	if (!new_mem || (new_mem->placement & TTM_PL_FLAG_SYSTEM)) {
379		if (bo->hw_res_handle)
380			virtio_gpu_cmd_resource_inval_backing(vgdev,
381							   bo->hw_res_handle);
382
383	} else if (new_mem->placement & TTM_PL_FLAG_TT) {
384		if (bo->hw_res_handle) {
385			virtio_gpu_object_attach(vgdev, bo, bo->hw_res_handle,
386						 NULL);
387		}
388	}
389}
390
391static void virtio_gpu_bo_swap_notify(struct ttm_buffer_object *tbo)
392{
393	struct virtio_gpu_object *bo;
394	struct virtio_gpu_device *vgdev;
395
396	bo = container_of(tbo, struct virtio_gpu_object, tbo);
397	vgdev = (struct virtio_gpu_device *)bo->gem_base.dev->dev_private;
398
399	if (bo->pages)
400		virtio_gpu_object_free_sg_table(bo);
401}
402
403static struct ttm_bo_driver virtio_gpu_bo_driver = {
404	.ttm_tt_create = &virtio_gpu_ttm_tt_create,
405	.invalidate_caches = &virtio_gpu_invalidate_caches,
406	.init_mem_type = &virtio_gpu_init_mem_type,
407	.eviction_valuable = ttm_bo_eviction_valuable,
408	.evict_flags = &virtio_gpu_evict_flags,
409	.move = &virtio_gpu_bo_move,
410	.verify_access = &virtio_gpu_verify_access,
411	.io_mem_reserve = &virtio_gpu_ttm_io_mem_reserve,
412	.io_mem_free = &virtio_gpu_ttm_io_mem_free,
413	.move_notify = &virtio_gpu_bo_move_notify,
414	.swap_notify = &virtio_gpu_bo_swap_notify,
415};
416
417int virtio_gpu_ttm_init(struct virtio_gpu_device *vgdev)
418{
419	int r;
420
421	r = virtio_gpu_ttm_global_init(vgdev);
422	if (r)
423		return r;
424	/* No others user of address space so set it to 0 */
425	r = ttm_bo_device_init(&vgdev->mman.bdev,
426			       vgdev->mman.bo_global_ref.ref.object,
427			       &virtio_gpu_bo_driver,
428			       vgdev->ddev->anon_inode->i_mapping,
429			       DRM_FILE_PAGE_OFFSET, 0);
430	if (r) {
431		DRM_ERROR("failed initializing buffer object driver(%d).\n", r);
432		goto err_dev_init;
433	}
434
435	r = ttm_bo_init_mm(&vgdev->mman.bdev, TTM_PL_TT, 0);
436	if (r) {
437		DRM_ERROR("Failed initializing GTT heap.\n");
438		goto err_mm_init;
439	}
440	return 0;
441
442err_mm_init:
443	ttm_bo_device_release(&vgdev->mman.bdev);
444err_dev_init:
445	virtio_gpu_ttm_global_fini(vgdev);
446	return r;
447}
448
449void virtio_gpu_ttm_fini(struct virtio_gpu_device *vgdev)
450{
451	ttm_bo_device_release(&vgdev->mman.bdev);
452	virtio_gpu_ttm_global_fini(vgdev);
453	DRM_INFO("virtio_gpu: ttm finalized\n");
454}