1 // SPDX-License-Identifier: GPL-2.0 OR MIT
2 /**************************************************************************
3  *
4  * Copyright 2014-2023 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,
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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,
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23  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
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26  **************************************************************************/
27 /*
28  * Treat context OTables as resources to make use of the resource
29  * backing MOB eviction mechanism, that is used to read back the COTable
30  * whenever the backing MOB is evicted.
31  */
32 
33 #include "vmwgfx_bo.h"
34 #include "vmwgfx_drv.h"
35 #include "vmwgfx_mksstat.h"
36 #include "vmwgfx_resource_priv.h"
37 #include "vmwgfx_so.h"
38 
39 #include <drm/ttm/ttm_placement.h>
40 
41 /**
42  * struct vmw_cotable - Context Object Table resource
43  *
44  * @res: struct vmw_resource we are deriving from.
45  * @ctx: non-refcounted pointer to the owning context.
46  * @size_read_back: Size of data read back during eviction.
47  * @seen_entries: Seen entries in command stream for this cotable.
48  * @type: The cotable type.
49  * @scrubbed: Whether the cotable has been scrubbed.
50  * @resource_list: List of resources in the cotable.
51  */
52 struct vmw_cotable {
53 	struct vmw_resource res;
54 	struct vmw_resource *ctx;
55 	size_t size_read_back;
56 	int seen_entries;
57 	u32 type;
58 	bool scrubbed;
59 	struct list_head resource_list;
60 };
61 
62 /**
63  * struct vmw_cotable_info - Static info about cotable types
64  *
65  * @min_initial_entries: Min number of initial intries at cotable allocation
66  * for this cotable type.
67  * @size: Size of each entry.
68  * @unbind_func: Unbind call-back function.
69  */
70 struct vmw_cotable_info {
71 	u32 min_initial_entries;
72 	u32 size;
73 	void (*unbind_func)(struct vmw_private *, struct list_head *,
74 			    bool);
75 };
76 
77 
78 /*
79  * Getting the initial size right is difficult because it all depends
80  * on what the userspace is doing. The sizes will be aligned up to
81  * a PAGE_SIZE so we just want to make sure that for majority of apps
82  * the initial number of entries doesn't require an immediate resize.
83  * For all cotables except SVGACOTableDXElementLayoutEntry and
84  * SVGACOTableDXBlendStateEntry the initial number of entries fits
85  * within the PAGE_SIZE. For SVGACOTableDXElementLayoutEntry and
86  * SVGACOTableDXBlendStateEntry we want to reserve two pages,
87  * because that's what all apps will require initially.
88  */
89 static const struct vmw_cotable_info co_info[] = {
90 	{1, sizeof(SVGACOTableDXRTViewEntry), &vmw_view_cotable_list_destroy},
91 	{1, sizeof(SVGACOTableDXDSViewEntry), &vmw_view_cotable_list_destroy},
92 	{1, sizeof(SVGACOTableDXSRViewEntry), &vmw_view_cotable_list_destroy},
93 	{PAGE_SIZE/sizeof(SVGACOTableDXElementLayoutEntry) + 1, sizeof(SVGACOTableDXElementLayoutEntry), NULL},
94 	{PAGE_SIZE/sizeof(SVGACOTableDXBlendStateEntry) + 1, sizeof(SVGACOTableDXBlendStateEntry), NULL},
95 	{1, sizeof(SVGACOTableDXDepthStencilEntry), NULL},
96 	{1, sizeof(SVGACOTableDXRasterizerStateEntry), NULL},
97 	{1, sizeof(SVGACOTableDXSamplerEntry), NULL},
98 	{1, sizeof(SVGACOTableDXStreamOutputEntry), &vmw_dx_streamoutput_cotable_list_scrub},
99 	{1, sizeof(SVGACOTableDXQueryEntry), NULL},
100 	{1, sizeof(SVGACOTableDXShaderEntry), &vmw_dx_shader_cotable_list_scrub},
101 	{1, sizeof(SVGACOTableDXUAViewEntry), &vmw_view_cotable_list_destroy}
102 };
103 
104 /*
105  * Cotables with bindings that we remove must be scrubbed first,
106  * otherwise, the device will swap in an invalid context when we remove
107  * bindings before scrubbing a cotable...
108  */
109 const SVGACOTableType vmw_cotable_scrub_order[] = {
110 	SVGA_COTABLE_RTVIEW,
111 	SVGA_COTABLE_DSVIEW,
112 	SVGA_COTABLE_SRVIEW,
113 	SVGA_COTABLE_DXSHADER,
114 	SVGA_COTABLE_ELEMENTLAYOUT,
115 	SVGA_COTABLE_BLENDSTATE,
116 	SVGA_COTABLE_DEPTHSTENCIL,
117 	SVGA_COTABLE_RASTERIZERSTATE,
118 	SVGA_COTABLE_SAMPLER,
119 	SVGA_COTABLE_STREAMOUTPUT,
120 	SVGA_COTABLE_DXQUERY,
121 	SVGA_COTABLE_UAVIEW,
122 };
123 
124 static int vmw_cotable_bind(struct vmw_resource *res,
125 			    struct ttm_validate_buffer *val_buf);
126 static int vmw_cotable_unbind(struct vmw_resource *res,
127 			      bool readback,
128 			      struct ttm_validate_buffer *val_buf);
129 static int vmw_cotable_create(struct vmw_resource *res);
130 static int vmw_cotable_destroy(struct vmw_resource *res);
131 
132 static const struct vmw_res_func vmw_cotable_func = {
133 	.res_type = vmw_res_cotable,
134 	.needs_guest_memory = true,
135 	.may_evict = true,
136 	.prio = 3,
137 	.dirty_prio = 3,
138 	.type_name = "context guest backed object tables",
139 	.domain = VMW_BO_DOMAIN_MOB,
140 	.busy_domain = VMW_BO_DOMAIN_MOB,
141 	.create = vmw_cotable_create,
142 	.destroy = vmw_cotable_destroy,
143 	.bind = vmw_cotable_bind,
144 	.unbind = vmw_cotable_unbind,
145 };
146 
147 /**
148  * vmw_cotable - Convert a struct vmw_resource pointer to a struct
149  * vmw_cotable pointer
150  *
151  * @res: Pointer to the resource.
152  */
153 static struct vmw_cotable *vmw_cotable(struct vmw_resource *res)
154 {
155 	return container_of(res, struct vmw_cotable, res);
156 }
157 
158 /**
159  * vmw_cotable_destroy - Cotable resource destroy callback
160  *
161  * @res: Pointer to the cotable resource.
162  *
163  * There is no device cotable destroy command, so this function only
164  * makes sure that the resource id is set to invalid.
165  */
166 static int vmw_cotable_destroy(struct vmw_resource *res)
167 {
168 	res->id = -1;
169 	return 0;
170 }
171 
172 /**
173  * vmw_cotable_unscrub - Undo a cotable unscrub operation
174  *
175  * @res: Pointer to the cotable resource
176  *
177  * This function issues commands to (re)bind the cotable to
178  * its backing mob, which needs to be validated and reserved at this point.
179  * This is identical to bind() except the function interface looks different.
180  */
181 static int vmw_cotable_unscrub(struct vmw_resource *res)
182 {
183 	struct vmw_cotable *vcotbl = vmw_cotable(res);
184 	struct vmw_private *dev_priv = res->dev_priv;
185 	struct ttm_buffer_object *bo = &res->guest_memory_bo->tbo;
186 	struct {
187 		SVGA3dCmdHeader header;
188 		SVGA3dCmdDXSetCOTable body;
189 	} *cmd;
190 
191 	WARN_ON_ONCE(bo->resource->mem_type != VMW_PL_MOB);
192 	dma_resv_assert_held(bo->base.resv);
193 
194 	cmd = VMW_CMD_RESERVE(dev_priv, sizeof(*cmd));
195 	if (!cmd)
196 		return -ENOMEM;
197 
198 	WARN_ON(vcotbl->ctx->id == SVGA3D_INVALID_ID);
199 	WARN_ON(bo->resource->mem_type != VMW_PL_MOB);
200 	cmd->header.id = SVGA_3D_CMD_DX_SET_COTABLE;
201 	cmd->header.size = sizeof(cmd->body);
202 	cmd->body.cid = vcotbl->ctx->id;
203 	cmd->body.type = vcotbl->type;
204 	cmd->body.mobid = bo->resource->start;
205 	cmd->body.validSizeInBytes = vcotbl->size_read_back;
206 
207 	vmw_cmd_commit_flush(dev_priv, sizeof(*cmd));
208 	vcotbl->scrubbed = false;
209 
210 	return 0;
211 }
212 
213 /**
214  * vmw_cotable_bind - Undo a cotable unscrub operation
215  *
216  * @res: Pointer to the cotable resource
217  * @val_buf: Pointer to a struct ttm_validate_buffer prepared by the caller
218  * for convenience / fencing.
219  *
220  * This function issues commands to (re)bind the cotable to
221  * its backing mob, which needs to be validated and reserved at this point.
222  */
223 static int vmw_cotable_bind(struct vmw_resource *res,
224 			    struct ttm_validate_buffer *val_buf)
225 {
226 	/*
227 	 * The create() callback may have changed @res->backup without
228 	 * the caller noticing, and with val_buf->bo still pointing to
229 	 * the old backup buffer. Although hackish, and not used currently,
230 	 * take the opportunity to correct the value here so that it's not
231 	 * misused in the future.
232 	 */
233 	val_buf->bo = &res->guest_memory_bo->tbo;
234 
235 	return vmw_cotable_unscrub(res);
236 }
237 
238 /**
239  * vmw_cotable_scrub - Scrub the cotable from the device.
240  *
241  * @res: Pointer to the cotable resource.
242  * @readback: Whether initiate a readback of the cotable data to the backup
243  * buffer.
244  *
245  * In some situations (context swapouts) it might be desirable to make the
246  * device forget about the cotable without performing a full unbind. A full
247  * unbind requires reserved backup buffers and it might not be possible to
248  * reserve them due to locking order violation issues. The vmw_cotable_scrub
249  * function implements a partial unbind() without that requirement but with the
250  * following restrictions.
251  * 1) Before the cotable is again used by the GPU, vmw_cotable_unscrub() must
252  *    be called.
253  * 2) Before the cotable backing buffer is used by the CPU, or during the
254  *    resource destruction, vmw_cotable_unbind() must be called.
255  */
256 int vmw_cotable_scrub(struct vmw_resource *res, bool readback)
257 {
258 	struct vmw_cotable *vcotbl = vmw_cotable(res);
259 	struct vmw_private *dev_priv = res->dev_priv;
260 	size_t submit_size;
261 
262 	struct {
263 		SVGA3dCmdHeader header;
264 		SVGA3dCmdDXReadbackCOTable body;
265 	} *cmd0;
266 	struct {
267 		SVGA3dCmdHeader header;
268 		SVGA3dCmdDXSetCOTable body;
269 	} *cmd1;
270 
271 	if (vcotbl->scrubbed)
272 		return 0;
273 
274 	if (co_info[vcotbl->type].unbind_func)
275 		co_info[vcotbl->type].unbind_func(dev_priv,
276 						  &vcotbl->resource_list,
277 						  readback);
278 	submit_size = sizeof(*cmd1);
279 	if (readback)
280 		submit_size += sizeof(*cmd0);
281 
282 	cmd1 = VMW_CMD_RESERVE(dev_priv, submit_size);
283 	if (!cmd1)
284 		return -ENOMEM;
285 
286 	vcotbl->size_read_back = 0;
287 	if (readback) {
288 		cmd0 = (void *) cmd1;
289 		cmd0->header.id = SVGA_3D_CMD_DX_READBACK_COTABLE;
290 		cmd0->header.size = sizeof(cmd0->body);
291 		cmd0->body.cid = vcotbl->ctx->id;
292 		cmd0->body.type = vcotbl->type;
293 		cmd1 = (void *) &cmd0[1];
294 		vcotbl->size_read_back = res->guest_memory_size;
295 	}
296 	cmd1->header.id = SVGA_3D_CMD_DX_SET_COTABLE;
297 	cmd1->header.size = sizeof(cmd1->body);
298 	cmd1->body.cid = vcotbl->ctx->id;
299 	cmd1->body.type = vcotbl->type;
300 	cmd1->body.mobid = SVGA3D_INVALID_ID;
301 	cmd1->body.validSizeInBytes = 0;
302 	vmw_cmd_commit_flush(dev_priv, submit_size);
303 	vcotbl->scrubbed = true;
304 
305 	/* Trigger a create() on next validate. */
306 	res->id = -1;
307 
308 	return 0;
309 }
310 
311 /**
312  * vmw_cotable_unbind - Cotable resource unbind callback
313  *
314  * @res: Pointer to the cotable resource.
315  * @readback: Whether to read back cotable data to the backup buffer.
316  * @val_buf: Pointer to a struct ttm_validate_buffer prepared by the caller
317  * for convenience / fencing.
318  *
319  * Unbinds the cotable from the device and fences the backup buffer.
320  */
321 static int vmw_cotable_unbind(struct vmw_resource *res,
322 			      bool readback,
323 			      struct ttm_validate_buffer *val_buf)
324 {
325 	struct vmw_cotable *vcotbl = vmw_cotable(res);
326 	struct vmw_private *dev_priv = res->dev_priv;
327 	struct ttm_buffer_object *bo = val_buf->bo;
328 	struct vmw_fence_obj *fence;
329 
330 	if (!vmw_resource_mob_attached(res))
331 		return 0;
332 
333 	WARN_ON_ONCE(bo->resource->mem_type != VMW_PL_MOB);
334 	dma_resv_assert_held(bo->base.resv);
335 
336 	mutex_lock(&dev_priv->binding_mutex);
337 	if (!vcotbl->scrubbed)
338 		vmw_dx_context_scrub_cotables(vcotbl->ctx, readback);
339 	mutex_unlock(&dev_priv->binding_mutex);
340 	(void) vmw_execbuf_fence_commands(NULL, dev_priv, &fence, NULL);
341 	vmw_bo_fence_single(bo, fence);
342 	if (likely(fence != NULL))
343 		vmw_fence_obj_unreference(&fence);
344 
345 	return 0;
346 }
347 
348 /**
349  * vmw_cotable_readback - Read back a cotable without unbinding.
350  *
351  * @res: The cotable resource.
352  *
353  * Reads back a cotable to its backing mob without scrubbing the MOB from
354  * the cotable. The MOB is fenced for subsequent CPU access.
355  */
356 static int vmw_cotable_readback(struct vmw_resource *res)
357 {
358 	struct vmw_cotable *vcotbl = vmw_cotable(res);
359 	struct vmw_private *dev_priv = res->dev_priv;
360 
361 	struct {
362 		SVGA3dCmdHeader header;
363 		SVGA3dCmdDXReadbackCOTable body;
364 	} *cmd;
365 	struct vmw_fence_obj *fence;
366 
367 	if (!vcotbl->scrubbed) {
368 		cmd = VMW_CMD_RESERVE(dev_priv, sizeof(*cmd));
369 		if (!cmd)
370 			return -ENOMEM;
371 
372 		cmd->header.id = SVGA_3D_CMD_DX_READBACK_COTABLE;
373 		cmd->header.size = sizeof(cmd->body);
374 		cmd->body.cid = vcotbl->ctx->id;
375 		cmd->body.type = vcotbl->type;
376 		vcotbl->size_read_back = res->guest_memory_size;
377 		vmw_cmd_commit(dev_priv, sizeof(*cmd));
378 	}
379 
380 	(void) vmw_execbuf_fence_commands(NULL, dev_priv, &fence, NULL);
381 	vmw_bo_fence_single(&res->guest_memory_bo->tbo, fence);
382 	vmw_fence_obj_unreference(&fence);
383 
384 	return 0;
385 }
386 
387 /**
388  * vmw_cotable_resize - Resize a cotable.
389  *
390  * @res: The cotable resource.
391  * @new_size: The new size.
392  *
393  * Resizes a cotable and binds the new backup buffer.
394  * On failure the cotable is left intact.
395  * Important! This function may not fail once the MOB switch has been
396  * committed to hardware. That would put the device context in an
397  * invalid state which we can't currently recover from.
398  */
399 static int vmw_cotable_resize(struct vmw_resource *res, size_t new_size)
400 {
401 	struct ttm_operation_ctx ctx = { false, false };
402 	struct vmw_private *dev_priv = res->dev_priv;
403 	struct vmw_cotable *vcotbl = vmw_cotable(res);
404 	struct vmw_bo *buf, *old_buf = res->guest_memory_bo;
405 	struct ttm_buffer_object *bo, *old_bo = &res->guest_memory_bo->tbo;
406 	size_t old_size = res->guest_memory_size;
407 	size_t old_size_read_back = vcotbl->size_read_back;
408 	size_t cur_size_read_back;
409 	struct ttm_bo_kmap_obj old_map, new_map;
410 	int ret;
411 	size_t i;
412 	struct vmw_bo_params bo_params = {
413 		.domain = VMW_BO_DOMAIN_MOB,
414 		.busy_domain = VMW_BO_DOMAIN_MOB,
415 		.bo_type = ttm_bo_type_device,
416 		.size = new_size,
417 		.pin = true
418 	};
419 
420 	MKS_STAT_TIME_DECL(MKSSTAT_KERN_COTABLE_RESIZE);
421 	MKS_STAT_TIME_PUSH(MKSSTAT_KERN_COTABLE_RESIZE);
422 
423 	ret = vmw_cotable_readback(res);
424 	if (ret)
425 		goto out_done;
426 
427 	cur_size_read_back = vcotbl->size_read_back;
428 	vcotbl->size_read_back = old_size_read_back;
429 
430 	/*
431 	 * While device is processing, Allocate and reserve a buffer object
432 	 * for the new COTable. Initially pin the buffer object to make sure
433 	 * we can use tryreserve without failure.
434 	 */
435 	ret = vmw_gem_object_create(dev_priv, &bo_params, &buf);
436 	if (ret) {
437 		DRM_ERROR("Failed initializing new cotable MOB.\n");
438 		goto out_done;
439 	}
440 
441 	bo = &buf->tbo;
442 	WARN_ON_ONCE(ttm_bo_reserve(bo, false, true, NULL));
443 
444 	ret = ttm_bo_wait(old_bo, false, false);
445 	if (unlikely(ret != 0)) {
446 		DRM_ERROR("Failed waiting for cotable unbind.\n");
447 		goto out_wait;
448 	}
449 
450 	/*
451 	 * Do a page by page copy of COTables. This eliminates slow vmap()s.
452 	 * This should really be a TTM utility.
453 	 */
454 	for (i = 0; i < PFN_UP(old_bo->resource->size); ++i) {
455 		bool dummy;
456 
457 		ret = ttm_bo_kmap(old_bo, i, 1, &old_map);
458 		if (unlikely(ret != 0)) {
459 			DRM_ERROR("Failed mapping old COTable on resize.\n");
460 			goto out_wait;
461 		}
462 		ret = ttm_bo_kmap(bo, i, 1, &new_map);
463 		if (unlikely(ret != 0)) {
464 			DRM_ERROR("Failed mapping new COTable on resize.\n");
465 			goto out_map_new;
466 		}
467 		memcpy(ttm_kmap_obj_virtual(&new_map, &dummy),
468 		       ttm_kmap_obj_virtual(&old_map, &dummy),
469 		       PAGE_SIZE);
470 		ttm_bo_kunmap(&new_map);
471 		ttm_bo_kunmap(&old_map);
472 	}
473 
474 	/* Unpin new buffer, and switch backup buffers. */
475 	vmw_bo_placement_set(buf,
476 			     VMW_BO_DOMAIN_MOB,
477 			     VMW_BO_DOMAIN_MOB);
478 	ret = ttm_bo_validate(bo, &buf->placement, &ctx);
479 	if (unlikely(ret != 0)) {
480 		DRM_ERROR("Failed validating new COTable backup buffer.\n");
481 		goto out_wait;
482 	}
483 
484 	vmw_resource_mob_detach(res);
485 	res->guest_memory_bo = buf;
486 	res->guest_memory_size = new_size;
487 	vcotbl->size_read_back = cur_size_read_back;
488 
489 	/*
490 	 * Now tell the device to switch. If this fails, then we need to
491 	 * revert the full resize.
492 	 */
493 	ret = vmw_cotable_unscrub(res);
494 	if (ret) {
495 		DRM_ERROR("Failed switching COTable backup buffer.\n");
496 		res->guest_memory_bo = old_buf;
497 		res->guest_memory_size = old_size;
498 		vcotbl->size_read_back = old_size_read_back;
499 		vmw_resource_mob_attach(res);
500 		goto out_wait;
501 	}
502 
503 	vmw_resource_mob_attach(res);
504 	/* Let go of the old mob. */
505 	vmw_user_bo_unref(&old_buf);
506 	res->id = vcotbl->type;
507 
508 	ret = dma_resv_reserve_fences(bo->base.resv, 1);
509 	if (unlikely(ret))
510 		goto out_wait;
511 
512 	/* Release the pin acquired in vmw_bo_create */
513 	ttm_bo_unpin(bo);
514 
515 	MKS_STAT_TIME_POP(MKSSTAT_KERN_COTABLE_RESIZE);
516 
517 	return 0;
518 
519 out_map_new:
520 	ttm_bo_kunmap(&old_map);
521 out_wait:
522 	ttm_bo_unpin(bo);
523 	ttm_bo_unreserve(bo);
524 	vmw_user_bo_unref(&buf);
525 
526 out_done:
527 	MKS_STAT_TIME_POP(MKSSTAT_KERN_COTABLE_RESIZE);
528 
529 	return ret;
530 }
531 
532 /**
533  * vmw_cotable_create - Cotable resource create callback
534  *
535  * @res: Pointer to a cotable resource.
536  *
537  * There is no separate create command for cotables, so this callback, which
538  * is called before bind() in the validation sequence is instead used for two
539  * things.
540  * 1) Unscrub the cotable if it is scrubbed and still attached to a backup
541  *    buffer.
542  * 2) Resize the cotable if needed.
543  */
544 static int vmw_cotable_create(struct vmw_resource *res)
545 {
546 	struct vmw_cotable *vcotbl = vmw_cotable(res);
547 	size_t new_size = res->guest_memory_size;
548 	size_t needed_size;
549 	int ret;
550 
551 	/* Check whether we need to resize the cotable */
552 	needed_size = (vcotbl->seen_entries + 1) * co_info[vcotbl->type].size;
553 	while (needed_size > new_size)
554 		new_size *= 2;
555 
556 	if (likely(new_size <= res->guest_memory_size)) {
557 		if (vcotbl->scrubbed && vmw_resource_mob_attached(res)) {
558 			ret = vmw_cotable_unscrub(res);
559 			if (ret)
560 				return ret;
561 		}
562 		res->id = vcotbl->type;
563 		return 0;
564 	}
565 
566 	return vmw_cotable_resize(res, new_size);
567 }
568 
569 /**
570  * vmw_hw_cotable_destroy - Cotable hw_destroy callback
571  *
572  * @res: Pointer to a cotable resource.
573  *
574  * The final (part of resource destruction) destroy callback.
575  */
576 static void vmw_hw_cotable_destroy(struct vmw_resource *res)
577 {
578 	(void) vmw_cotable_destroy(res);
579 }
580 
581 /**
582  * vmw_cotable_free - Cotable resource destructor
583  *
584  * @res: Pointer to a cotable resource.
585  */
586 static void vmw_cotable_free(struct vmw_resource *res)
587 {
588 	kfree(res);
589 }
590 
591 /**
592  * vmw_cotable_alloc - Create a cotable resource
593  *
594  * @dev_priv: Pointer to a device private struct.
595  * @ctx: Pointer to the context resource.
596  * The cotable resource will not add a refcount.
597  * @type: The cotable type.
598  */
599 struct vmw_resource *vmw_cotable_alloc(struct vmw_private *dev_priv,
600 				       struct vmw_resource *ctx,
601 				       u32 type)
602 {
603 	struct vmw_cotable *vcotbl;
604 	int ret;
605 	u32 num_entries;
606 
607 	vcotbl = kzalloc(sizeof(*vcotbl), GFP_KERNEL);
608 	if (unlikely(!vcotbl)) {
609 		ret = -ENOMEM;
610 		goto out_no_alloc;
611 	}
612 
613 	ret = vmw_resource_init(dev_priv, &vcotbl->res, true,
614 				vmw_cotable_free, &vmw_cotable_func);
615 	if (unlikely(ret != 0))
616 		goto out_no_init;
617 
618 	INIT_LIST_HEAD(&vcotbl->resource_list);
619 	vcotbl->res.id = type;
620 	vcotbl->res.guest_memory_size = PAGE_SIZE;
621 	num_entries = PAGE_SIZE / co_info[type].size;
622 	if (num_entries < co_info[type].min_initial_entries) {
623 		vcotbl->res.guest_memory_size = co_info[type].min_initial_entries *
624 			co_info[type].size;
625 		vcotbl->res.guest_memory_size = PFN_ALIGN(vcotbl->res.guest_memory_size);
626 	}
627 
628 	vcotbl->scrubbed = true;
629 	vcotbl->seen_entries = -1;
630 	vcotbl->type = type;
631 	vcotbl->ctx = ctx;
632 
633 	vcotbl->res.hw_destroy = vmw_hw_cotable_destroy;
634 
635 	return &vcotbl->res;
636 
637 out_no_init:
638 	kfree(vcotbl);
639 out_no_alloc:
640 	return ERR_PTR(ret);
641 }
642 
643 /**
644  * vmw_cotable_notify - Notify the cotable about an item creation
645  *
646  * @res: Pointer to a cotable resource.
647  * @id: Item id.
648  */
649 int vmw_cotable_notify(struct vmw_resource *res, int id)
650 {
651 	struct vmw_cotable *vcotbl = vmw_cotable(res);
652 
653 	if (id < 0 || id >= SVGA_COTABLE_MAX_IDS) {
654 		DRM_ERROR("Illegal COTable id. Type is %u. Id is %d\n",
655 			  (unsigned) vcotbl->type, id);
656 		return -EINVAL;
657 	}
658 
659 	if (vcotbl->seen_entries < id) {
660 		/* Trigger a call to create() on next validate */
661 		res->id = -1;
662 		vcotbl->seen_entries = id;
663 	}
664 
665 	return 0;
666 }
667 
668 /**
669  * vmw_cotable_add_resource - add a view to the cotable's list of active views.
670  *
671  * @res: pointer struct vmw_resource representing the cotable.
672  * @head: pointer to the struct list_head member of the resource, dedicated
673  * to the cotable active resource list.
674  */
675 void vmw_cotable_add_resource(struct vmw_resource *res, struct list_head *head)
676 {
677 	struct vmw_cotable *vcotbl =
678 		container_of(res, struct vmw_cotable, res);
679 
680 	list_add_tail(head, &vcotbl->resource_list);
681 }
682