1 // SPDX-License-Identifier: GPL-2.0 OR MIT
2 /**************************************************************************
3  *
4  * Copyright 2012-2015 VMware, Inc., Palo Alto, CA., USA
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a
7  * copy of this software and associated documentation files (the
8  * "Software"), to deal in the Software without restriction, including
9  * without limitation the rights to use, copy, modify, merge, publish,
10  * distribute, sub license, and/or sell copies of the Software, and to
11  * permit persons to whom the Software is furnished to do so, subject to
12  * the following conditions:
13  *
14  * The above copyright notice and this permission notice (including the
15  * next paragraph) shall be included in all copies or substantial portions
16  * of the Software.
17  *
18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
21  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
22  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
23  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
24  * USE OR OTHER DEALINGS IN THE SOFTWARE.
25  *
26  **************************************************************************/
27 
28 #include "vmwgfx_drv.h"
29 
30 /*
31  * If we set up the screen target otable, screen objects stop working.
32  */
33 
34 #define VMW_OTABLE_SETUP_SUB ((VMWGFX_ENABLE_SCREEN_TARGET_OTABLE ? 0 : 1))
35 
36 #ifdef CONFIG_64BIT
37 #define VMW_PPN_SIZE 8
38 #define VMW_MOBFMT_PTDEPTH_0 SVGA3D_MOBFMT_PTDEPTH64_0
39 #define VMW_MOBFMT_PTDEPTH_1 SVGA3D_MOBFMT_PTDEPTH64_1
40 #define VMW_MOBFMT_PTDEPTH_2 SVGA3D_MOBFMT_PTDEPTH64_2
41 #else
42 #define VMW_PPN_SIZE 4
43 #define VMW_MOBFMT_PTDEPTH_0 SVGA3D_MOBFMT_PTDEPTH_0
44 #define VMW_MOBFMT_PTDEPTH_1 SVGA3D_MOBFMT_PTDEPTH_1
45 #define VMW_MOBFMT_PTDEPTH_2 SVGA3D_MOBFMT_PTDEPTH_2
46 #endif
47 
48 /*
49  * struct vmw_mob - Structure containing page table and metadata for a
50  * Guest Memory OBject.
51  *
52  * @num_pages       Number of pages that make up the page table.
53  * @pt_level        The indirection level of the page table. 0-2.
54  * @pt_root_page    DMA address of the level 0 page of the page table.
55  */
56 struct vmw_mob {
57 	struct ttm_buffer_object *pt_bo;
58 	unsigned long num_pages;
59 	unsigned pt_level;
60 	dma_addr_t pt_root_page;
61 	uint32_t id;
62 };
63 
64 /*
65  * struct vmw_otable - Guest Memory OBject table metadata
66  *
67  * @size:           Size of the table (page-aligned).
68  * @page_table:     Pointer to a struct vmw_mob holding the page table.
69  */
70 static const struct vmw_otable pre_dx_tables[] = {
71 	{VMWGFX_NUM_MOB * SVGA3D_OTABLE_MOB_ENTRY_SIZE, NULL, true},
72 	{VMWGFX_NUM_GB_SURFACE * SVGA3D_OTABLE_SURFACE_ENTRY_SIZE, NULL, true},
73 	{VMWGFX_NUM_GB_CONTEXT * SVGA3D_OTABLE_CONTEXT_ENTRY_SIZE, NULL, true},
74 	{VMWGFX_NUM_GB_SHADER * SVGA3D_OTABLE_SHADER_ENTRY_SIZE, NULL, true},
75 	{VMWGFX_NUM_GB_SCREEN_TARGET * SVGA3D_OTABLE_SCREEN_TARGET_ENTRY_SIZE,
76 	 NULL, VMWGFX_ENABLE_SCREEN_TARGET_OTABLE}
77 };
78 
79 static const struct vmw_otable dx_tables[] = {
80 	{VMWGFX_NUM_MOB * SVGA3D_OTABLE_MOB_ENTRY_SIZE, NULL, true},
81 	{VMWGFX_NUM_GB_SURFACE * SVGA3D_OTABLE_SURFACE_ENTRY_SIZE, NULL, true},
82 	{VMWGFX_NUM_GB_CONTEXT * SVGA3D_OTABLE_CONTEXT_ENTRY_SIZE, NULL, true},
83 	{VMWGFX_NUM_GB_SHADER * SVGA3D_OTABLE_SHADER_ENTRY_SIZE, NULL, true},
84 	{VMWGFX_NUM_GB_SCREEN_TARGET * SVGA3D_OTABLE_SCREEN_TARGET_ENTRY_SIZE,
85 	 NULL, VMWGFX_ENABLE_SCREEN_TARGET_OTABLE},
86 	{VMWGFX_NUM_DXCONTEXT * sizeof(SVGAOTableDXContextEntry), NULL, true},
87 };
88 
89 static int vmw_mob_pt_populate(struct vmw_private *dev_priv,
90 			       struct vmw_mob *mob);
91 static void vmw_mob_pt_setup(struct vmw_mob *mob,
92 			     struct vmw_piter data_iter,
93 			     unsigned long num_data_pages);
94 
95 /*
96  * vmw_setup_otable_base - Issue an object table base setup command to
97  * the device
98  *
99  * @dev_priv:       Pointer to a device private structure
100  * @type:           Type of object table base
101  * @offset          Start of table offset into dev_priv::otable_bo
102  * @otable          Pointer to otable metadata;
103  *
104  * This function returns -ENOMEM if it fails to reserve fifo space,
105  * and may block waiting for fifo space.
106  */
107 static int vmw_setup_otable_base(struct vmw_private *dev_priv,
108 				 SVGAOTableType type,
109 				 struct ttm_buffer_object *otable_bo,
110 				 unsigned long offset,
111 				 struct vmw_otable *otable)
112 {
113 	struct {
114 		SVGA3dCmdHeader header;
115 		SVGA3dCmdSetOTableBase64 body;
116 	} *cmd;
117 	struct vmw_mob *mob;
118 	const struct vmw_sg_table *vsgt;
119 	struct vmw_piter iter;
120 	int ret;
121 
122 	BUG_ON(otable->page_table != NULL);
123 
124 	vsgt = vmw_bo_sg_table(otable_bo);
125 	vmw_piter_start(&iter, vsgt, offset >> PAGE_SHIFT);
126 	WARN_ON(!vmw_piter_next(&iter));
127 
128 	mob = vmw_mob_create(otable->size >> PAGE_SHIFT);
129 	if (unlikely(mob == NULL)) {
130 		DRM_ERROR("Failed creating OTable page table.\n");
131 		return -ENOMEM;
132 	}
133 
134 	if (otable->size <= PAGE_SIZE) {
135 		mob->pt_level = VMW_MOBFMT_PTDEPTH_0;
136 		mob->pt_root_page = vmw_piter_dma_addr(&iter);
137 	} else if (vsgt->num_regions == 1) {
138 		mob->pt_level = SVGA3D_MOBFMT_RANGE;
139 		mob->pt_root_page = vmw_piter_dma_addr(&iter);
140 	} else {
141 		ret = vmw_mob_pt_populate(dev_priv, mob);
142 		if (unlikely(ret != 0))
143 			goto out_no_populate;
144 
145 		vmw_mob_pt_setup(mob, iter, otable->size >> PAGE_SHIFT);
146 		mob->pt_level += VMW_MOBFMT_PTDEPTH_1 - SVGA3D_MOBFMT_PTDEPTH_1;
147 	}
148 
149 	cmd = vmw_fifo_reserve(dev_priv, sizeof(*cmd));
150 	if (unlikely(cmd == NULL)) {
151 		DRM_ERROR("Failed reserving FIFO space for OTable setup.\n");
152 		ret = -ENOMEM;
153 		goto out_no_fifo;
154 	}
155 
156 	memset(cmd, 0, sizeof(*cmd));
157 	cmd->header.id = SVGA_3D_CMD_SET_OTABLE_BASE64;
158 	cmd->header.size = sizeof(cmd->body);
159 	cmd->body.type = type;
160 	cmd->body.baseAddress = mob->pt_root_page >> PAGE_SHIFT;
161 	cmd->body.sizeInBytes = otable->size;
162 	cmd->body.validSizeInBytes = 0;
163 	cmd->body.ptDepth = mob->pt_level;
164 
165 	/*
166 	 * The device doesn't support this, But the otable size is
167 	 * determined at compile-time, so this BUG shouldn't trigger
168 	 * randomly.
169 	 */
170 	BUG_ON(mob->pt_level == VMW_MOBFMT_PTDEPTH_2);
171 
172 	vmw_fifo_commit(dev_priv, sizeof(*cmd));
173 	otable->page_table = mob;
174 
175 	return 0;
176 
177 out_no_fifo:
178 out_no_populate:
179 	vmw_mob_destroy(mob);
180 	return ret;
181 }
182 
183 /*
184  * vmw_takedown_otable_base - Issue an object table base takedown command
185  * to the device
186  *
187  * @dev_priv:       Pointer to a device private structure
188  * @type:           Type of object table base
189  *
190  */
191 static void vmw_takedown_otable_base(struct vmw_private *dev_priv,
192 				     SVGAOTableType type,
193 				     struct vmw_otable *otable)
194 {
195 	struct {
196 		SVGA3dCmdHeader header;
197 		SVGA3dCmdSetOTableBase body;
198 	} *cmd;
199 	struct ttm_buffer_object *bo;
200 
201 	if (otable->page_table == NULL)
202 		return;
203 
204 	bo = otable->page_table->pt_bo;
205 	cmd = vmw_fifo_reserve(dev_priv, sizeof(*cmd));
206 	if (unlikely(cmd == NULL)) {
207 		DRM_ERROR("Failed reserving FIFO space for OTable "
208 			  "takedown.\n");
209 		return;
210 	}
211 
212 	memset(cmd, 0, sizeof(*cmd));
213 	cmd->header.id = SVGA_3D_CMD_SET_OTABLE_BASE;
214 	cmd->header.size = sizeof(cmd->body);
215 	cmd->body.type = type;
216 	cmd->body.baseAddress = 0;
217 	cmd->body.sizeInBytes = 0;
218 	cmd->body.validSizeInBytes = 0;
219 	cmd->body.ptDepth = SVGA3D_MOBFMT_INVALID;
220 	vmw_fifo_commit(dev_priv, sizeof(*cmd));
221 
222 	if (bo) {
223 		int ret;
224 
225 		ret = ttm_bo_reserve(bo, false, true, NULL);
226 		BUG_ON(ret != 0);
227 
228 		vmw_bo_fence_single(bo, NULL);
229 		ttm_bo_unreserve(bo);
230 	}
231 
232 	vmw_mob_destroy(otable->page_table);
233 	otable->page_table = NULL;
234 }
235 
236 
237 static int vmw_otable_batch_setup(struct vmw_private *dev_priv,
238 				  struct vmw_otable_batch *batch)
239 {
240 	unsigned long offset;
241 	unsigned long bo_size;
242 	struct vmw_otable *otables = batch->otables;
243 	struct ttm_operation_ctx ctx = {
244 		.interruptible = false,
245 		.no_wait_gpu = false
246 	};
247 	SVGAOTableType i;
248 	int ret;
249 
250 	bo_size = 0;
251 	for (i = 0; i < batch->num_otables; ++i) {
252 		if (!otables[i].enabled)
253 			continue;
254 
255 		otables[i].size =
256 			(otables[i].size + PAGE_SIZE - 1) & PAGE_MASK;
257 		bo_size += otables[i].size;
258 	}
259 
260 	ret = ttm_bo_create(&dev_priv->bdev, bo_size,
261 			    ttm_bo_type_device,
262 			    &vmw_sys_ne_placement,
263 			    0, false, &batch->otable_bo);
264 
265 	if (unlikely(ret != 0))
266 		goto out_no_bo;
267 
268 	ret = ttm_bo_reserve(batch->otable_bo, false, true, NULL);
269 	BUG_ON(ret != 0);
270 	ret = vmw_bo_driver.ttm_tt_populate(batch->otable_bo->ttm, &ctx);
271 	if (unlikely(ret != 0))
272 		goto out_unreserve;
273 	ret = vmw_bo_map_dma(batch->otable_bo);
274 	if (unlikely(ret != 0))
275 		goto out_unreserve;
276 
277 	ttm_bo_unreserve(batch->otable_bo);
278 
279 	offset = 0;
280 	for (i = 0; i < batch->num_otables; ++i) {
281 		if (!batch->otables[i].enabled)
282 			continue;
283 
284 		ret = vmw_setup_otable_base(dev_priv, i, batch->otable_bo,
285 					    offset,
286 					    &otables[i]);
287 		if (unlikely(ret != 0))
288 			goto out_no_setup;
289 		offset += otables[i].size;
290 	}
291 
292 	return 0;
293 
294 out_unreserve:
295 	ttm_bo_unreserve(batch->otable_bo);
296 out_no_setup:
297 	for (i = 0; i < batch->num_otables; ++i) {
298 		if (batch->otables[i].enabled)
299 			vmw_takedown_otable_base(dev_priv, i,
300 						 &batch->otables[i]);
301 	}
302 
303 	ttm_bo_unref(&batch->otable_bo);
304 out_no_bo:
305 	return ret;
306 }
307 
308 /*
309  * vmw_otables_setup - Set up guest backed memory object tables
310  *
311  * @dev_priv:       Pointer to a device private structure
312  *
313  * Takes care of the device guest backed surface
314  * initialization, by setting up the guest backed memory object tables.
315  * Returns 0 on success and various error codes on failure. A successful return
316  * means the object tables can be taken down using the vmw_otables_takedown
317  * function.
318  */
319 int vmw_otables_setup(struct vmw_private *dev_priv)
320 {
321 	struct vmw_otable **otables = &dev_priv->otable_batch.otables;
322 	int ret;
323 
324 	if (dev_priv->has_dx) {
325 		*otables = kmemdup(dx_tables, sizeof(dx_tables), GFP_KERNEL);
326 		if (!(*otables))
327 			return -ENOMEM;
328 
329 		dev_priv->otable_batch.num_otables = ARRAY_SIZE(dx_tables);
330 	} else {
331 		*otables = kmemdup(pre_dx_tables, sizeof(pre_dx_tables),
332 				   GFP_KERNEL);
333 		if (!(*otables))
334 			return -ENOMEM;
335 
336 		dev_priv->otable_batch.num_otables = ARRAY_SIZE(pre_dx_tables);
337 	}
338 
339 	ret = vmw_otable_batch_setup(dev_priv, &dev_priv->otable_batch);
340 	if (unlikely(ret != 0))
341 		goto out_setup;
342 
343 	return 0;
344 
345 out_setup:
346 	kfree(*otables);
347 	return ret;
348 }
349 
350 static void vmw_otable_batch_takedown(struct vmw_private *dev_priv,
351 			       struct vmw_otable_batch *batch)
352 {
353 	SVGAOTableType i;
354 	struct ttm_buffer_object *bo = batch->otable_bo;
355 	int ret;
356 
357 	for (i = 0; i < batch->num_otables; ++i)
358 		if (batch->otables[i].enabled)
359 			vmw_takedown_otable_base(dev_priv, i,
360 						 &batch->otables[i]);
361 
362 	ret = ttm_bo_reserve(bo, false, true, NULL);
363 	BUG_ON(ret != 0);
364 
365 	vmw_bo_fence_single(bo, NULL);
366 	ttm_bo_unreserve(bo);
367 
368 	ttm_bo_unref(&batch->otable_bo);
369 }
370 
371 /*
372  * vmw_otables_takedown - Take down guest backed memory object tables
373  *
374  * @dev_priv:       Pointer to a device private structure
375  *
376  * Take down the Guest Memory Object tables.
377  */
378 void vmw_otables_takedown(struct vmw_private *dev_priv)
379 {
380 	vmw_otable_batch_takedown(dev_priv, &dev_priv->otable_batch);
381 	kfree(dev_priv->otable_batch.otables);
382 }
383 
384 /*
385  * vmw_mob_calculate_pt_pages - Calculate the number of page table pages
386  * needed for a guest backed memory object.
387  *
388  * @data_pages:  Number of data pages in the memory object buffer.
389  */
390 static unsigned long vmw_mob_calculate_pt_pages(unsigned long data_pages)
391 {
392 	unsigned long data_size = data_pages * PAGE_SIZE;
393 	unsigned long tot_size = 0;
394 
395 	while (likely(data_size > PAGE_SIZE)) {
396 		data_size = DIV_ROUND_UP(data_size, PAGE_SIZE);
397 		data_size *= VMW_PPN_SIZE;
398 		tot_size += (data_size + PAGE_SIZE - 1) & PAGE_MASK;
399 	}
400 
401 	return tot_size >> PAGE_SHIFT;
402 }
403 
404 /*
405  * vmw_mob_create - Create a mob, but don't populate it.
406  *
407  * @data_pages:  Number of data pages of the underlying buffer object.
408  */
409 struct vmw_mob *vmw_mob_create(unsigned long data_pages)
410 {
411 	struct vmw_mob *mob = kzalloc(sizeof(*mob), GFP_KERNEL);
412 
413 	if (unlikely(!mob))
414 		return NULL;
415 
416 	mob->num_pages = vmw_mob_calculate_pt_pages(data_pages);
417 
418 	return mob;
419 }
420 
421 /*
422  * vmw_mob_pt_populate - Populate the mob pagetable
423  *
424  * @mob:         Pointer to the mob the pagetable of which we want to
425  *               populate.
426  *
427  * This function allocates memory to be used for the pagetable, and
428  * adjusts TTM memory accounting accordingly. Returns ENOMEM if
429  * memory resources aren't sufficient and may cause TTM buffer objects
430  * to be swapped out by using the TTM memory accounting function.
431  */
432 static int vmw_mob_pt_populate(struct vmw_private *dev_priv,
433 			       struct vmw_mob *mob)
434 {
435 	int ret;
436 	struct ttm_operation_ctx ctx = {
437 		.interruptible = false,
438 		.no_wait_gpu = false
439 	};
440 
441 	BUG_ON(mob->pt_bo != NULL);
442 
443 	ret = ttm_bo_create(&dev_priv->bdev, mob->num_pages * PAGE_SIZE,
444 			    ttm_bo_type_device,
445 			    &vmw_sys_ne_placement,
446 			    0, false, &mob->pt_bo);
447 	if (unlikely(ret != 0))
448 		return ret;
449 
450 	ret = ttm_bo_reserve(mob->pt_bo, false, true, NULL);
451 
452 	BUG_ON(ret != 0);
453 	ret = vmw_bo_driver.ttm_tt_populate(mob->pt_bo->ttm, &ctx);
454 	if (unlikely(ret != 0))
455 		goto out_unreserve;
456 	ret = vmw_bo_map_dma(mob->pt_bo);
457 	if (unlikely(ret != 0))
458 		goto out_unreserve;
459 
460 	ttm_bo_unreserve(mob->pt_bo);
461 
462 	return 0;
463 
464 out_unreserve:
465 	ttm_bo_unreserve(mob->pt_bo);
466 	ttm_bo_unref(&mob->pt_bo);
467 
468 	return ret;
469 }
470 
471 /**
472  * vmw_mob_assign_ppn - Assign a value to a page table entry
473  *
474  * @addr: Pointer to pointer to page table entry.
475  * @val: The page table entry
476  *
477  * Assigns a value to a page table entry pointed to by *@addr and increments
478  * *@addr according to the page table entry size.
479  */
480 #if (VMW_PPN_SIZE == 8)
481 static void vmw_mob_assign_ppn(u32 **addr, dma_addr_t val)
482 {
483 	*((u64 *) *addr) = val >> PAGE_SHIFT;
484 	*addr += 2;
485 }
486 #else
487 static void vmw_mob_assign_ppn(u32 **addr, dma_addr_t val)
488 {
489 	*(*addr)++ = val >> PAGE_SHIFT;
490 }
491 #endif
492 
493 /*
494  * vmw_mob_build_pt - Build a pagetable
495  *
496  * @data_addr:      Array of DMA addresses to the underlying buffer
497  *                  object's data pages.
498  * @num_data_pages: Number of buffer object data pages.
499  * @pt_pages:       Array of page pointers to the page table pages.
500  *
501  * Returns the number of page table pages actually used.
502  * Uses atomic kmaps of highmem pages to avoid TLB thrashing.
503  */
504 static unsigned long vmw_mob_build_pt(struct vmw_piter *data_iter,
505 				      unsigned long num_data_pages,
506 				      struct vmw_piter *pt_iter)
507 {
508 	unsigned long pt_size = num_data_pages * VMW_PPN_SIZE;
509 	unsigned long num_pt_pages = DIV_ROUND_UP(pt_size, PAGE_SIZE);
510 	unsigned long pt_page;
511 	u32 *addr, *save_addr;
512 	unsigned long i;
513 	struct page *page;
514 
515 	for (pt_page = 0; pt_page < num_pt_pages; ++pt_page) {
516 		page = vmw_piter_page(pt_iter);
517 
518 		save_addr = addr = kmap_atomic(page);
519 
520 		for (i = 0; i < PAGE_SIZE / VMW_PPN_SIZE; ++i) {
521 			vmw_mob_assign_ppn(&addr,
522 					   vmw_piter_dma_addr(data_iter));
523 			if (unlikely(--num_data_pages == 0))
524 				break;
525 			WARN_ON(!vmw_piter_next(data_iter));
526 		}
527 		kunmap_atomic(save_addr);
528 		vmw_piter_next(pt_iter);
529 	}
530 
531 	return num_pt_pages;
532 }
533 
534 /*
535  * vmw_mob_build_pt - Set up a multilevel mob pagetable
536  *
537  * @mob:            Pointer to a mob whose page table needs setting up.
538  * @data_addr       Array of DMA addresses to the buffer object's data
539  *                  pages.
540  * @num_data_pages: Number of buffer object data pages.
541  *
542  * Uses tail recursion to set up a multilevel mob page table.
543  */
544 static void vmw_mob_pt_setup(struct vmw_mob *mob,
545 			     struct vmw_piter data_iter,
546 			     unsigned long num_data_pages)
547 {
548 	unsigned long num_pt_pages = 0;
549 	struct ttm_buffer_object *bo = mob->pt_bo;
550 	struct vmw_piter save_pt_iter;
551 	struct vmw_piter pt_iter;
552 	const struct vmw_sg_table *vsgt;
553 	int ret;
554 
555 	ret = ttm_bo_reserve(bo, false, true, NULL);
556 	BUG_ON(ret != 0);
557 
558 	vsgt = vmw_bo_sg_table(bo);
559 	vmw_piter_start(&pt_iter, vsgt, 0);
560 	BUG_ON(!vmw_piter_next(&pt_iter));
561 	mob->pt_level = 0;
562 	while (likely(num_data_pages > 1)) {
563 		++mob->pt_level;
564 		BUG_ON(mob->pt_level > 2);
565 		save_pt_iter = pt_iter;
566 		num_pt_pages = vmw_mob_build_pt(&data_iter, num_data_pages,
567 						&pt_iter);
568 		data_iter = save_pt_iter;
569 		num_data_pages = num_pt_pages;
570 	}
571 
572 	mob->pt_root_page = vmw_piter_dma_addr(&save_pt_iter);
573 	ttm_bo_unreserve(bo);
574 }
575 
576 /*
577  * vmw_mob_destroy - Destroy a mob, unpopulating first if necessary.
578  *
579  * @mob:            Pointer to a mob to destroy.
580  */
581 void vmw_mob_destroy(struct vmw_mob *mob)
582 {
583 	if (mob->pt_bo)
584 		ttm_bo_unref(&mob->pt_bo);
585 	kfree(mob);
586 }
587 
588 /*
589  * vmw_mob_unbind - Hide a mob from the device.
590  *
591  * @dev_priv:       Pointer to a device private.
592  * @mob_id:         Device id of the mob to unbind.
593  */
594 void vmw_mob_unbind(struct vmw_private *dev_priv,
595 		    struct vmw_mob *mob)
596 {
597 	struct {
598 		SVGA3dCmdHeader header;
599 		SVGA3dCmdDestroyGBMob body;
600 	} *cmd;
601 	int ret;
602 	struct ttm_buffer_object *bo = mob->pt_bo;
603 
604 	if (bo) {
605 		ret = ttm_bo_reserve(bo, false, true, NULL);
606 		/*
607 		 * Noone else should be using this buffer.
608 		 */
609 		BUG_ON(ret != 0);
610 	}
611 
612 	cmd = vmw_fifo_reserve(dev_priv, sizeof(*cmd));
613 	if (unlikely(cmd == NULL)) {
614 		DRM_ERROR("Failed reserving FIFO space for Memory "
615 			  "Object unbinding.\n");
616 	} else {
617 		cmd->header.id = SVGA_3D_CMD_DESTROY_GB_MOB;
618 		cmd->header.size = sizeof(cmd->body);
619 		cmd->body.mobid = mob->id;
620 		vmw_fifo_commit(dev_priv, sizeof(*cmd));
621 	}
622 	if (bo) {
623 		vmw_bo_fence_single(bo, NULL);
624 		ttm_bo_unreserve(bo);
625 	}
626 	vmw_fifo_resource_dec(dev_priv);
627 }
628 
629 /*
630  * vmw_mob_bind - Make a mob visible to the device after first
631  *                populating it if necessary.
632  *
633  * @dev_priv:       Pointer to a device private.
634  * @mob:            Pointer to the mob we're making visible.
635  * @data_addr:      Array of DMA addresses to the data pages of the underlying
636  *                  buffer object.
637  * @num_data_pages: Number of data pages of the underlying buffer
638  *                  object.
639  * @mob_id:         Device id of the mob to bind
640  *
641  * This function is intended to be interfaced with the ttm_tt backend
642  * code.
643  */
644 int vmw_mob_bind(struct vmw_private *dev_priv,
645 		 struct vmw_mob *mob,
646 		 const struct vmw_sg_table *vsgt,
647 		 unsigned long num_data_pages,
648 		 int32_t mob_id)
649 {
650 	int ret;
651 	bool pt_set_up = false;
652 	struct vmw_piter data_iter;
653 	struct {
654 		SVGA3dCmdHeader header;
655 		SVGA3dCmdDefineGBMob64 body;
656 	} *cmd;
657 
658 	mob->id = mob_id;
659 	vmw_piter_start(&data_iter, vsgt, 0);
660 	if (unlikely(!vmw_piter_next(&data_iter)))
661 		return 0;
662 
663 	if (likely(num_data_pages == 1)) {
664 		mob->pt_level = VMW_MOBFMT_PTDEPTH_0;
665 		mob->pt_root_page = vmw_piter_dma_addr(&data_iter);
666 	} else if (vsgt->num_regions == 1) {
667 		mob->pt_level = SVGA3D_MOBFMT_RANGE;
668 		mob->pt_root_page = vmw_piter_dma_addr(&data_iter);
669 	} else if (unlikely(mob->pt_bo == NULL)) {
670 		ret = vmw_mob_pt_populate(dev_priv, mob);
671 		if (unlikely(ret != 0))
672 			return ret;
673 
674 		vmw_mob_pt_setup(mob, data_iter, num_data_pages);
675 		pt_set_up = true;
676 		mob->pt_level += VMW_MOBFMT_PTDEPTH_1 - SVGA3D_MOBFMT_PTDEPTH_1;
677 	}
678 
679 	vmw_fifo_resource_inc(dev_priv);
680 
681 	cmd = vmw_fifo_reserve(dev_priv, sizeof(*cmd));
682 	if (unlikely(cmd == NULL)) {
683 		DRM_ERROR("Failed reserving FIFO space for Memory "
684 			  "Object binding.\n");
685 		goto out_no_cmd_space;
686 	}
687 
688 	cmd->header.id = SVGA_3D_CMD_DEFINE_GB_MOB64;
689 	cmd->header.size = sizeof(cmd->body);
690 	cmd->body.mobid = mob_id;
691 	cmd->body.ptDepth = mob->pt_level;
692 	cmd->body.base = mob->pt_root_page >> PAGE_SHIFT;
693 	cmd->body.sizeInBytes = num_data_pages * PAGE_SIZE;
694 
695 	vmw_fifo_commit(dev_priv, sizeof(*cmd));
696 
697 	return 0;
698 
699 out_no_cmd_space:
700 	vmw_fifo_resource_dec(dev_priv);
701 	if (pt_set_up)
702 		ttm_bo_unref(&mob->pt_bo);
703 
704 	return -ENOMEM;
705 }
706