xref: /linux/drivers/gpu/drm/i915/gem/i915_gem_context.c (revision 815e260a18a3af4dab59025ee99a7156c0e8b5e0)
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2011-2012 Intel Corporation
4  */
5 
6 /*
7  * This file implements HW context support. On gen5+ a HW context consists of an
8  * opaque GPU object which is referenced at times of context saves and restores.
9  * With RC6 enabled, the context is also referenced as the GPU enters and exists
10  * from RC6 (GPU has it's own internal power context, except on gen5). Though
11  * something like a context does exist for the media ring, the code only
12  * supports contexts for the render ring.
13  *
14  * In software, there is a distinction between contexts created by the user,
15  * and the default HW context. The default HW context is used by GPU clients
16  * that do not request setup of their own hardware context. The default
17  * context's state is never restored to help prevent programming errors. This
18  * would happen if a client ran and piggy-backed off another clients GPU state.
19  * The default context only exists to give the GPU some offset to load as the
20  * current to invoke a save of the context we actually care about. In fact, the
21  * code could likely be constructed, albeit in a more complicated fashion, to
22  * never use the default context, though that limits the driver's ability to
23  * swap out, and/or destroy other contexts.
24  *
25  * All other contexts are created as a request by the GPU client. These contexts
26  * store GPU state, and thus allow GPU clients to not re-emit state (and
27  * potentially query certain state) at any time. The kernel driver makes
28  * certain that the appropriate commands are inserted.
29  *
30  * The context life cycle is semi-complicated in that context BOs may live
31  * longer than the context itself because of the way the hardware, and object
32  * tracking works. Below is a very crude representation of the state machine
33  * describing the context life.
34  *                                         refcount     pincount     active
35  * S0: initial state                          0            0           0
36  * S1: context created                        1            0           0
37  * S2: context is currently running           2            1           X
38  * S3: GPU referenced, but not current        2            0           1
39  * S4: context is current, but destroyed      1            1           0
40  * S5: like S3, but destroyed                 1            0           1
41  *
42  * The most common (but not all) transitions:
43  * S0->S1: client creates a context
44  * S1->S2: client submits execbuf with context
45  * S2->S3: other clients submits execbuf with context
46  * S3->S1: context object was retired
47  * S3->S2: clients submits another execbuf
48  * S2->S4: context destroy called with current context
49  * S3->S5->S0: destroy path
50  * S4->S5->S0: destroy path on current context
51  *
52  * There are two confusing terms used above:
53  *  The "current context" means the context which is currently running on the
54  *  GPU. The GPU has loaded its state already and has stored away the gtt
55  *  offset of the BO. The GPU is not actively referencing the data at this
56  *  offset, but it will on the next context switch. The only way to avoid this
57  *  is to do a GPU reset.
58  *
59  *  An "active context' is one which was previously the "current context" and is
60  *  on the active list waiting for the next context switch to occur. Until this
61  *  happens, the object must remain at the same gtt offset. It is therefore
62  *  possible to destroy a context, but it is still active.
63  *
64  */
65 
66 #include <linux/highmem.h>
67 #include <linux/log2.h>
68 #include <linux/nospec.h>
69 
70 #include <drm/drm_cache.h>
71 #include <drm/drm_print.h>
72 #include <drm/drm_syncobj.h>
73 
74 #include "gt/gen6_ppgtt.h"
75 #include "gt/intel_context.h"
76 #include "gt/intel_context_param.h"
77 #include "gt/intel_engine_heartbeat.h"
78 #include "gt/intel_engine_user.h"
79 #include "gt/intel_gpu_commands.h"
80 #include "gt/intel_ring.h"
81 #include "gt/shmem_utils.h"
82 
83 #include "pxp/intel_pxp.h"
84 
85 #include "i915_file_private.h"
86 #include "i915_gem_context.h"
87 #include "i915_trace.h"
88 #include "i915_user_extensions.h"
89 
90 #define ALL_L3_SLICES(dev) (1 << NUM_L3_SLICES(dev)) - 1
91 
92 static struct kmem_cache *slab_luts;
93 
94 struct i915_lut_handle *i915_lut_handle_alloc(void)
95 {
96 	return kmem_cache_alloc(slab_luts, GFP_KERNEL);
97 }
98 
99 void i915_lut_handle_free(struct i915_lut_handle *lut)
100 {
101 	return kmem_cache_free(slab_luts, lut);
102 }
103 
104 static void lut_close(struct i915_gem_context *ctx)
105 {
106 	struct radix_tree_iter iter;
107 	void __rcu **slot;
108 
109 	mutex_lock(&ctx->lut_mutex);
110 	rcu_read_lock();
111 	radix_tree_for_each_slot(slot, &ctx->handles_vma, &iter, 0) {
112 		struct i915_vma *vma = rcu_dereference_raw(*slot);
113 		struct drm_i915_gem_object *obj = vma->obj;
114 		struct i915_lut_handle *lut;
115 
116 		if (!kref_get_unless_zero(&obj->base.refcount))
117 			continue;
118 
119 		spin_lock(&obj->lut_lock);
120 		list_for_each_entry(lut, &obj->lut_list, obj_link) {
121 			if (lut->ctx != ctx)
122 				continue;
123 
124 			if (lut->handle != iter.index)
125 				continue;
126 
127 			list_del(&lut->obj_link);
128 			break;
129 		}
130 		spin_unlock(&obj->lut_lock);
131 
132 		if (&lut->obj_link != &obj->lut_list) {
133 			i915_lut_handle_free(lut);
134 			radix_tree_iter_delete(&ctx->handles_vma, &iter, slot);
135 			i915_vma_close(vma);
136 			i915_gem_object_put(obj);
137 		}
138 
139 		i915_gem_object_put(obj);
140 	}
141 	rcu_read_unlock();
142 	mutex_unlock(&ctx->lut_mutex);
143 }
144 
145 static struct intel_context *
146 lookup_user_engine(struct i915_gem_context *ctx,
147 		   unsigned long flags,
148 		   const struct i915_engine_class_instance *ci)
149 #define LOOKUP_USER_INDEX BIT(0)
150 {
151 	int idx;
152 
153 	if (!!(flags & LOOKUP_USER_INDEX) != i915_gem_context_user_engines(ctx))
154 		return ERR_PTR(-EINVAL);
155 
156 	if (!i915_gem_context_user_engines(ctx)) {
157 		struct intel_engine_cs *engine;
158 
159 		engine = intel_engine_lookup_user(ctx->i915,
160 						  ci->engine_class,
161 						  ci->engine_instance);
162 		if (!engine)
163 			return ERR_PTR(-EINVAL);
164 
165 		idx = engine->legacy_idx;
166 	} else {
167 		idx = ci->engine_instance;
168 	}
169 
170 	return i915_gem_context_get_engine(ctx, idx);
171 }
172 
173 static int validate_priority(struct drm_i915_private *i915,
174 			     const struct drm_i915_gem_context_param *args)
175 {
176 	s64 priority = args->value;
177 
178 	if (args->size)
179 		return -EINVAL;
180 
181 	if (!(i915->caps.scheduler & I915_SCHEDULER_CAP_PRIORITY))
182 		return -ENODEV;
183 
184 	if (priority > I915_CONTEXT_MAX_USER_PRIORITY ||
185 	    priority < I915_CONTEXT_MIN_USER_PRIORITY)
186 		return -EINVAL;
187 
188 	if (priority > I915_CONTEXT_DEFAULT_PRIORITY &&
189 	    !capable(CAP_SYS_NICE))
190 		return -EPERM;
191 
192 	return 0;
193 }
194 
195 static void proto_context_close(struct drm_i915_private *i915,
196 				struct i915_gem_proto_context *pc)
197 {
198 	int i;
199 
200 	if (pc->pxp_wakeref)
201 		intel_runtime_pm_put(&i915->runtime_pm, pc->pxp_wakeref);
202 	if (pc->vm)
203 		i915_vm_put(pc->vm);
204 	if (pc->user_engines) {
205 		for (i = 0; i < pc->num_user_engines; i++)
206 			kfree(pc->user_engines[i].siblings);
207 		kfree(pc->user_engines);
208 	}
209 	kfree(pc);
210 }
211 
212 static int proto_context_set_persistence(struct drm_i915_private *i915,
213 					 struct i915_gem_proto_context *pc,
214 					 bool persist)
215 {
216 	if (persist) {
217 		/*
218 		 * Only contexts that are short-lived [that will expire or be
219 		 * reset] are allowed to survive past termination. We require
220 		 * hangcheck to ensure that the persistent requests are healthy.
221 		 */
222 		if (!i915->params.enable_hangcheck)
223 			return -EINVAL;
224 
225 		pc->user_flags |= BIT(UCONTEXT_PERSISTENCE);
226 	} else {
227 		/* To cancel a context we use "preempt-to-idle" */
228 		if (!(i915->caps.scheduler & I915_SCHEDULER_CAP_PREEMPTION))
229 			return -ENODEV;
230 
231 		/*
232 		 * If the cancel fails, we then need to reset, cleanly!
233 		 *
234 		 * If the per-engine reset fails, all hope is lost! We resort
235 		 * to a full GPU reset in that unlikely case, but realistically
236 		 * if the engine could not reset, the full reset does not fare
237 		 * much better. The damage has been done.
238 		 *
239 		 * However, if we cannot reset an engine by itself, we cannot
240 		 * cleanup a hanging persistent context without causing
241 		 * collateral damage, and we should not pretend we can by
242 		 * exposing the interface.
243 		 */
244 		if (!intel_has_reset_engine(to_gt(i915)))
245 			return -ENODEV;
246 
247 		pc->user_flags &= ~BIT(UCONTEXT_PERSISTENCE);
248 	}
249 
250 	return 0;
251 }
252 
253 static int proto_context_set_protected(struct drm_i915_private *i915,
254 				       struct i915_gem_proto_context *pc,
255 				       bool protected)
256 {
257 	int ret = 0;
258 
259 	if (!protected) {
260 		pc->uses_protected_content = false;
261 	} else if (!intel_pxp_is_enabled(i915->pxp)) {
262 		ret = -ENODEV;
263 	} else if ((pc->user_flags & BIT(UCONTEXT_RECOVERABLE)) ||
264 		   !(pc->user_flags & BIT(UCONTEXT_BANNABLE))) {
265 		ret = -EPERM;
266 	} else {
267 		pc->uses_protected_content = true;
268 
269 		/*
270 		 * protected context usage requires the PXP session to be up,
271 		 * which in turn requires the device to be active.
272 		 */
273 		pc->pxp_wakeref = intel_runtime_pm_get(&i915->runtime_pm);
274 
275 		if (!intel_pxp_is_active(i915->pxp))
276 			ret = intel_pxp_start(i915->pxp);
277 	}
278 
279 	return ret;
280 }
281 
282 static struct i915_gem_proto_context *
283 proto_context_create(struct drm_i915_file_private *fpriv,
284 		     struct drm_i915_private *i915, unsigned int flags)
285 {
286 	struct i915_gem_proto_context *pc, *err;
287 
288 	pc = kzalloc(sizeof(*pc), GFP_KERNEL);
289 	if (!pc)
290 		return ERR_PTR(-ENOMEM);
291 
292 	pc->fpriv = fpriv;
293 	pc->num_user_engines = -1;
294 	pc->user_engines = NULL;
295 	pc->user_flags = BIT(UCONTEXT_BANNABLE) |
296 			 BIT(UCONTEXT_RECOVERABLE);
297 	if (i915->params.enable_hangcheck)
298 		pc->user_flags |= BIT(UCONTEXT_PERSISTENCE);
299 	pc->sched.priority = I915_PRIORITY_NORMAL;
300 
301 	if (flags & I915_CONTEXT_CREATE_FLAGS_SINGLE_TIMELINE) {
302 		if (!HAS_EXECLISTS(i915)) {
303 			err = ERR_PTR(-EINVAL);
304 			goto proto_close;
305 		}
306 		pc->single_timeline = true;
307 	}
308 
309 	return pc;
310 
311 proto_close:
312 	proto_context_close(i915, pc);
313 	return err;
314 }
315 
316 static int proto_context_register_locked(struct drm_i915_file_private *fpriv,
317 					 struct i915_gem_proto_context *pc,
318 					 u32 *id)
319 {
320 	int ret;
321 	void *old;
322 
323 	lockdep_assert_held(&fpriv->proto_context_lock);
324 
325 	ret = xa_alloc(&fpriv->context_xa, id, NULL, xa_limit_32b, GFP_KERNEL);
326 	if (ret)
327 		return ret;
328 
329 	old = xa_store(&fpriv->proto_context_xa, *id, pc, GFP_KERNEL);
330 	if (xa_is_err(old)) {
331 		xa_erase(&fpriv->context_xa, *id);
332 		return xa_err(old);
333 	}
334 	WARN_ON(old);
335 
336 	return 0;
337 }
338 
339 static int proto_context_register(struct drm_i915_file_private *fpriv,
340 				  struct i915_gem_proto_context *pc,
341 				  u32 *id)
342 {
343 	int ret;
344 
345 	mutex_lock(&fpriv->proto_context_lock);
346 	ret = proto_context_register_locked(fpriv, pc, id);
347 	mutex_unlock(&fpriv->proto_context_lock);
348 
349 	return ret;
350 }
351 
352 static struct i915_address_space *
353 i915_gem_vm_lookup(struct drm_i915_file_private *file_priv, u32 id)
354 {
355 	struct i915_address_space *vm;
356 
357 	xa_lock(&file_priv->vm_xa);
358 	vm = xa_load(&file_priv->vm_xa, id);
359 	if (vm)
360 		kref_get(&vm->ref);
361 	xa_unlock(&file_priv->vm_xa);
362 
363 	return vm;
364 }
365 
366 static int set_proto_ctx_vm(struct drm_i915_file_private *fpriv,
367 			    struct i915_gem_proto_context *pc,
368 			    const struct drm_i915_gem_context_param *args)
369 {
370 	struct drm_i915_private *i915 = fpriv->i915;
371 	struct i915_address_space *vm;
372 
373 	if (args->size)
374 		return -EINVAL;
375 
376 	if (!HAS_FULL_PPGTT(i915))
377 		return -ENODEV;
378 
379 	if (upper_32_bits(args->value))
380 		return -ENOENT;
381 
382 	vm = i915_gem_vm_lookup(fpriv, args->value);
383 	if (!vm)
384 		return -ENOENT;
385 
386 	if (pc->vm)
387 		i915_vm_put(pc->vm);
388 	pc->vm = vm;
389 
390 	return 0;
391 }
392 
393 struct set_proto_ctx_engines {
394 	struct drm_i915_private *i915;
395 	unsigned num_engines;
396 	struct i915_gem_proto_engine *engines;
397 };
398 
399 static int
400 set_proto_ctx_engines_balance(struct i915_user_extension __user *base,
401 			      void *data)
402 {
403 	struct i915_context_engines_load_balance __user *ext =
404 		container_of_user(base, typeof(*ext), base);
405 	const struct set_proto_ctx_engines *set = data;
406 	struct drm_i915_private *i915 = set->i915;
407 	struct intel_engine_cs **siblings;
408 	u16 num_siblings, idx;
409 	unsigned int n;
410 	int err;
411 
412 	if (!HAS_EXECLISTS(i915))
413 		return -ENODEV;
414 
415 	if (get_user(idx, &ext->engine_index))
416 		return -EFAULT;
417 
418 	if (idx >= set->num_engines) {
419 		drm_dbg(&i915->drm, "Invalid placement value, %d >= %d\n",
420 			idx, set->num_engines);
421 		return -EINVAL;
422 	}
423 
424 	idx = array_index_nospec(idx, set->num_engines);
425 	if (set->engines[idx].type != I915_GEM_ENGINE_TYPE_INVALID) {
426 		drm_dbg(&i915->drm,
427 			"Invalid placement[%d], already occupied\n", idx);
428 		return -EEXIST;
429 	}
430 
431 	if (get_user(num_siblings, &ext->num_siblings))
432 		return -EFAULT;
433 
434 	err = check_user_mbz(&ext->flags);
435 	if (err)
436 		return err;
437 
438 	err = check_user_mbz(&ext->mbz64);
439 	if (err)
440 		return err;
441 
442 	if (num_siblings == 0)
443 		return 0;
444 
445 	siblings = kmalloc_array(num_siblings, sizeof(*siblings), GFP_KERNEL);
446 	if (!siblings)
447 		return -ENOMEM;
448 
449 	for (n = 0; n < num_siblings; n++) {
450 		struct i915_engine_class_instance ci;
451 
452 		if (copy_from_user(&ci, &ext->engines[n], sizeof(ci))) {
453 			err = -EFAULT;
454 			goto err_siblings;
455 		}
456 
457 		siblings[n] = intel_engine_lookup_user(i915,
458 						       ci.engine_class,
459 						       ci.engine_instance);
460 		if (!siblings[n]) {
461 			drm_dbg(&i915->drm,
462 				"Invalid sibling[%d]: { class:%d, inst:%d }\n",
463 				n, ci.engine_class, ci.engine_instance);
464 			err = -EINVAL;
465 			goto err_siblings;
466 		}
467 	}
468 
469 	if (num_siblings == 1) {
470 		set->engines[idx].type = I915_GEM_ENGINE_TYPE_PHYSICAL;
471 		set->engines[idx].engine = siblings[0];
472 		kfree(siblings);
473 	} else {
474 		set->engines[idx].type = I915_GEM_ENGINE_TYPE_BALANCED;
475 		set->engines[idx].num_siblings = num_siblings;
476 		set->engines[idx].siblings = siblings;
477 	}
478 
479 	return 0;
480 
481 err_siblings:
482 	kfree(siblings);
483 
484 	return err;
485 }
486 
487 static int
488 set_proto_ctx_engines_bond(struct i915_user_extension __user *base, void *data)
489 {
490 	struct i915_context_engines_bond __user *ext =
491 		container_of_user(base, typeof(*ext), base);
492 	const struct set_proto_ctx_engines *set = data;
493 	struct drm_i915_private *i915 = set->i915;
494 	struct i915_engine_class_instance ci;
495 	struct intel_engine_cs *master;
496 	u16 idx, num_bonds;
497 	int err, n;
498 
499 	if (GRAPHICS_VER(i915) >= 12 && !IS_TIGERLAKE(i915) &&
500 	    !IS_ROCKETLAKE(i915) && !IS_ALDERLAKE_S(i915)) {
501 		drm_dbg(&i915->drm,
502 			"Bonding not supported on this platform\n");
503 		return -ENODEV;
504 	}
505 
506 	if (get_user(idx, &ext->virtual_index))
507 		return -EFAULT;
508 
509 	if (idx >= set->num_engines) {
510 		drm_dbg(&i915->drm,
511 			"Invalid index for virtual engine: %d >= %d\n",
512 			idx, set->num_engines);
513 		return -EINVAL;
514 	}
515 
516 	idx = array_index_nospec(idx, set->num_engines);
517 	if (set->engines[idx].type == I915_GEM_ENGINE_TYPE_INVALID) {
518 		drm_dbg(&i915->drm, "Invalid engine at %d\n", idx);
519 		return -EINVAL;
520 	}
521 
522 	if (set->engines[idx].type != I915_GEM_ENGINE_TYPE_PHYSICAL) {
523 		drm_dbg(&i915->drm,
524 			"Bonding with virtual engines not allowed\n");
525 		return -EINVAL;
526 	}
527 
528 	err = check_user_mbz(&ext->flags);
529 	if (err)
530 		return err;
531 
532 	for (n = 0; n < ARRAY_SIZE(ext->mbz64); n++) {
533 		err = check_user_mbz(&ext->mbz64[n]);
534 		if (err)
535 			return err;
536 	}
537 
538 	if (copy_from_user(&ci, &ext->master, sizeof(ci)))
539 		return -EFAULT;
540 
541 	master = intel_engine_lookup_user(i915,
542 					  ci.engine_class,
543 					  ci.engine_instance);
544 	if (!master) {
545 		drm_dbg(&i915->drm,
546 			"Unrecognised master engine: { class:%u, instance:%u }\n",
547 			ci.engine_class, ci.engine_instance);
548 		return -EINVAL;
549 	}
550 
551 	if (intel_engine_uses_guc(master)) {
552 		drm_dbg(&i915->drm, "bonding extension not supported with GuC submission");
553 		return -ENODEV;
554 	}
555 
556 	if (get_user(num_bonds, &ext->num_bonds))
557 		return -EFAULT;
558 
559 	for (n = 0; n < num_bonds; n++) {
560 		struct intel_engine_cs *bond;
561 
562 		if (copy_from_user(&ci, &ext->engines[n], sizeof(ci)))
563 			return -EFAULT;
564 
565 		bond = intel_engine_lookup_user(i915,
566 						ci.engine_class,
567 						ci.engine_instance);
568 		if (!bond) {
569 			drm_dbg(&i915->drm,
570 				"Unrecognised engine[%d] for bonding: { class:%d, instance: %d }\n",
571 				n, ci.engine_class, ci.engine_instance);
572 			return -EINVAL;
573 		}
574 	}
575 
576 	return 0;
577 }
578 
579 static int
580 set_proto_ctx_engines_parallel_submit(struct i915_user_extension __user *base,
581 				      void *data)
582 {
583 	struct i915_context_engines_parallel_submit __user *ext =
584 		container_of_user(base, typeof(*ext), base);
585 	const struct set_proto_ctx_engines *set = data;
586 	struct drm_i915_private *i915 = set->i915;
587 	struct i915_engine_class_instance prev_engine;
588 	u64 flags;
589 	int err = 0, n, i, j;
590 	u16 slot, width, num_siblings;
591 	struct intel_engine_cs **siblings = NULL;
592 	intel_engine_mask_t prev_mask;
593 
594 	if (get_user(slot, &ext->engine_index))
595 		return -EFAULT;
596 
597 	if (get_user(width, &ext->width))
598 		return -EFAULT;
599 
600 	if (get_user(num_siblings, &ext->num_siblings))
601 		return -EFAULT;
602 
603 	if (!intel_uc_uses_guc_submission(&to_gt(i915)->uc) &&
604 	    num_siblings != 1) {
605 		drm_dbg(&i915->drm, "Only 1 sibling (%d) supported in non-GuC mode\n",
606 			num_siblings);
607 		return -EINVAL;
608 	}
609 
610 	if (slot >= set->num_engines) {
611 		drm_dbg(&i915->drm, "Invalid placement value, %d >= %d\n",
612 			slot, set->num_engines);
613 		return -EINVAL;
614 	}
615 
616 	if (set->engines[slot].type != I915_GEM_ENGINE_TYPE_INVALID) {
617 		drm_dbg(&i915->drm,
618 			"Invalid placement[%d], already occupied\n", slot);
619 		return -EINVAL;
620 	}
621 
622 	if (get_user(flags, &ext->flags))
623 		return -EFAULT;
624 
625 	if (flags) {
626 		drm_dbg(&i915->drm, "Unknown flags 0x%02llx", flags);
627 		return -EINVAL;
628 	}
629 
630 	for (n = 0; n < ARRAY_SIZE(ext->mbz64); n++) {
631 		err = check_user_mbz(&ext->mbz64[n]);
632 		if (err)
633 			return err;
634 	}
635 
636 	if (width < 2) {
637 		drm_dbg(&i915->drm, "Width (%d) < 2\n", width);
638 		return -EINVAL;
639 	}
640 
641 	if (num_siblings < 1) {
642 		drm_dbg(&i915->drm, "Number siblings (%d) < 1\n",
643 			num_siblings);
644 		return -EINVAL;
645 	}
646 
647 	siblings = kmalloc_array(num_siblings * width,
648 				 sizeof(*siblings),
649 				 GFP_KERNEL);
650 	if (!siblings)
651 		return -ENOMEM;
652 
653 	/* Create contexts / engines */
654 	for (i = 0; i < width; ++i) {
655 		intel_engine_mask_t current_mask = 0;
656 
657 		for (j = 0; j < num_siblings; ++j) {
658 			struct i915_engine_class_instance ci;
659 
660 			n = i * num_siblings + j;
661 			if (copy_from_user(&ci, &ext->engines[n], sizeof(ci))) {
662 				err = -EFAULT;
663 				goto out_err;
664 			}
665 
666 			siblings[n] =
667 				intel_engine_lookup_user(i915, ci.engine_class,
668 							 ci.engine_instance);
669 			if (!siblings[n]) {
670 				drm_dbg(&i915->drm,
671 					"Invalid sibling[%d]: { class:%d, inst:%d }\n",
672 					n, ci.engine_class, ci.engine_instance);
673 				err = -EINVAL;
674 				goto out_err;
675 			}
676 
677 			/*
678 			 * We don't support breadcrumb handshake on these
679 			 * classes
680 			 */
681 			if (siblings[n]->class == RENDER_CLASS ||
682 			    siblings[n]->class == COMPUTE_CLASS) {
683 				err = -EINVAL;
684 				goto out_err;
685 			}
686 
687 			if (n) {
688 				if (prev_engine.engine_class !=
689 				    ci.engine_class) {
690 					drm_dbg(&i915->drm,
691 						"Mismatched class %d, %d\n",
692 						prev_engine.engine_class,
693 						ci.engine_class);
694 					err = -EINVAL;
695 					goto out_err;
696 				}
697 			}
698 
699 			prev_engine = ci;
700 			current_mask |= siblings[n]->logical_mask;
701 		}
702 
703 		if (i > 0) {
704 			if (current_mask != prev_mask << 1) {
705 				drm_dbg(&i915->drm,
706 					"Non contiguous logical mask 0x%x, 0x%x\n",
707 					prev_mask, current_mask);
708 				err = -EINVAL;
709 				goto out_err;
710 			}
711 		}
712 		prev_mask = current_mask;
713 	}
714 
715 	set->engines[slot].type = I915_GEM_ENGINE_TYPE_PARALLEL;
716 	set->engines[slot].num_siblings = num_siblings;
717 	set->engines[slot].width = width;
718 	set->engines[slot].siblings = siblings;
719 
720 	return 0;
721 
722 out_err:
723 	kfree(siblings);
724 
725 	return err;
726 }
727 
728 static const i915_user_extension_fn set_proto_ctx_engines_extensions[] = {
729 	[I915_CONTEXT_ENGINES_EXT_LOAD_BALANCE] = set_proto_ctx_engines_balance,
730 	[I915_CONTEXT_ENGINES_EXT_BOND] = set_proto_ctx_engines_bond,
731 	[I915_CONTEXT_ENGINES_EXT_PARALLEL_SUBMIT] =
732 		set_proto_ctx_engines_parallel_submit,
733 };
734 
735 static int set_proto_ctx_engines(struct drm_i915_file_private *fpriv,
736 			         struct i915_gem_proto_context *pc,
737 			         const struct drm_i915_gem_context_param *args)
738 {
739 	struct drm_i915_private *i915 = fpriv->i915;
740 	struct set_proto_ctx_engines set = { .i915 = i915 };
741 	struct i915_context_param_engines __user *user =
742 		u64_to_user_ptr(args->value);
743 	unsigned int n;
744 	u64 extensions;
745 	int err;
746 
747 	if (pc->num_user_engines >= 0) {
748 		drm_dbg(&i915->drm, "Cannot set engines twice");
749 		return -EINVAL;
750 	}
751 
752 	if (args->size < sizeof(*user) ||
753 	    !IS_ALIGNED(args->size - sizeof(*user), sizeof(*user->engines))) {
754 		drm_dbg(&i915->drm, "Invalid size for engine array: %d\n",
755 			args->size);
756 		return -EINVAL;
757 	}
758 
759 	set.num_engines = (args->size - sizeof(*user)) / sizeof(*user->engines);
760 	/* RING_MASK has no shift so we can use it directly here */
761 	if (set.num_engines > I915_EXEC_RING_MASK + 1)
762 		return -EINVAL;
763 
764 	set.engines = kmalloc_array(set.num_engines, sizeof(*set.engines), GFP_KERNEL);
765 	if (!set.engines)
766 		return -ENOMEM;
767 
768 	for (n = 0; n < set.num_engines; n++) {
769 		struct i915_engine_class_instance ci;
770 		struct intel_engine_cs *engine;
771 
772 		if (copy_from_user(&ci, &user->engines[n], sizeof(ci))) {
773 			kfree(set.engines);
774 			return -EFAULT;
775 		}
776 
777 		memset(&set.engines[n], 0, sizeof(set.engines[n]));
778 
779 		if (ci.engine_class == (u16)I915_ENGINE_CLASS_INVALID &&
780 		    ci.engine_instance == (u16)I915_ENGINE_CLASS_INVALID_NONE)
781 			continue;
782 
783 		engine = intel_engine_lookup_user(i915,
784 						  ci.engine_class,
785 						  ci.engine_instance);
786 		if (!engine) {
787 			drm_dbg(&i915->drm,
788 				"Invalid engine[%d]: { class:%d, instance:%d }\n",
789 				n, ci.engine_class, ci.engine_instance);
790 			kfree(set.engines);
791 			return -ENOENT;
792 		}
793 
794 		set.engines[n].type = I915_GEM_ENGINE_TYPE_PHYSICAL;
795 		set.engines[n].engine = engine;
796 	}
797 
798 	err = -EFAULT;
799 	if (!get_user(extensions, &user->extensions))
800 		err = i915_user_extensions(u64_to_user_ptr(extensions),
801 					   set_proto_ctx_engines_extensions,
802 					   ARRAY_SIZE(set_proto_ctx_engines_extensions),
803 					   &set);
804 	if (err) {
805 		kfree(set.engines);
806 		return err;
807 	}
808 
809 	pc->num_user_engines = set.num_engines;
810 	pc->user_engines = set.engines;
811 
812 	return 0;
813 }
814 
815 static int set_proto_ctx_sseu(struct drm_i915_file_private *fpriv,
816 			      struct i915_gem_proto_context *pc,
817 			      struct drm_i915_gem_context_param *args)
818 {
819 	struct drm_i915_private *i915 = fpriv->i915;
820 	struct drm_i915_gem_context_param_sseu user_sseu;
821 	struct intel_sseu *sseu;
822 	int ret;
823 
824 	if (args->size < sizeof(user_sseu))
825 		return -EINVAL;
826 
827 	if (GRAPHICS_VER(i915) != 11)
828 		return -ENODEV;
829 
830 	if (copy_from_user(&user_sseu, u64_to_user_ptr(args->value),
831 			   sizeof(user_sseu)))
832 		return -EFAULT;
833 
834 	if (user_sseu.rsvd)
835 		return -EINVAL;
836 
837 	if (user_sseu.flags & ~(I915_CONTEXT_SSEU_FLAG_ENGINE_INDEX))
838 		return -EINVAL;
839 
840 	if (!!(user_sseu.flags & I915_CONTEXT_SSEU_FLAG_ENGINE_INDEX) != (pc->num_user_engines >= 0))
841 		return -EINVAL;
842 
843 	if (pc->num_user_engines >= 0) {
844 		int idx = user_sseu.engine.engine_instance;
845 		struct i915_gem_proto_engine *pe;
846 
847 		if (idx >= pc->num_user_engines)
848 			return -EINVAL;
849 
850 		idx = array_index_nospec(idx, pc->num_user_engines);
851 		pe = &pc->user_engines[idx];
852 
853 		/* Only render engine supports RPCS configuration. */
854 		if (pe->engine->class != RENDER_CLASS)
855 			return -EINVAL;
856 
857 		sseu = &pe->sseu;
858 	} else {
859 		/* Only render engine supports RPCS configuration. */
860 		if (user_sseu.engine.engine_class != I915_ENGINE_CLASS_RENDER)
861 			return -EINVAL;
862 
863 		/* There is only one render engine */
864 		if (user_sseu.engine.engine_instance != 0)
865 			return -EINVAL;
866 
867 		sseu = &pc->legacy_rcs_sseu;
868 	}
869 
870 	ret = i915_gem_user_to_context_sseu(to_gt(i915), &user_sseu, sseu);
871 	if (ret)
872 		return ret;
873 
874 	args->size = sizeof(user_sseu);
875 
876 	return 0;
877 }
878 
879 static int set_proto_ctx_param(struct drm_i915_file_private *fpriv,
880 			       struct i915_gem_proto_context *pc,
881 			       struct drm_i915_gem_context_param *args)
882 {
883 	struct drm_i915_private *i915 = fpriv->i915;
884 	int ret = 0;
885 
886 	switch (args->param) {
887 	case I915_CONTEXT_PARAM_NO_ERROR_CAPTURE:
888 		if (args->size)
889 			ret = -EINVAL;
890 		else if (args->value)
891 			pc->user_flags |= BIT(UCONTEXT_NO_ERROR_CAPTURE);
892 		else
893 			pc->user_flags &= ~BIT(UCONTEXT_NO_ERROR_CAPTURE);
894 		break;
895 
896 	case I915_CONTEXT_PARAM_BANNABLE:
897 		if (args->size)
898 			ret = -EINVAL;
899 		else if (!capable(CAP_SYS_ADMIN) && !args->value)
900 			ret = -EPERM;
901 		else if (args->value)
902 			pc->user_flags |= BIT(UCONTEXT_BANNABLE);
903 		else if (pc->uses_protected_content)
904 			ret = -EPERM;
905 		else
906 			pc->user_flags &= ~BIT(UCONTEXT_BANNABLE);
907 		break;
908 
909 	case I915_CONTEXT_PARAM_LOW_LATENCY:
910 		if (intel_uc_uses_guc_submission(&to_gt(i915)->uc))
911 			pc->user_flags |= BIT(UCONTEXT_LOW_LATENCY);
912 		else
913 			ret = -EINVAL;
914 		break;
915 
916 	case I915_CONTEXT_PARAM_RECOVERABLE:
917 		if (args->size)
918 			ret = -EINVAL;
919 		else if (!args->value)
920 			pc->user_flags &= ~BIT(UCONTEXT_RECOVERABLE);
921 		else if (pc->uses_protected_content)
922 			ret = -EPERM;
923 		else
924 			pc->user_flags |= BIT(UCONTEXT_RECOVERABLE);
925 		break;
926 
927 	case I915_CONTEXT_PARAM_PRIORITY:
928 		ret = validate_priority(fpriv->i915, args);
929 		if (!ret)
930 			pc->sched.priority = args->value;
931 		break;
932 
933 	case I915_CONTEXT_PARAM_SSEU:
934 		ret = set_proto_ctx_sseu(fpriv, pc, args);
935 		break;
936 
937 	case I915_CONTEXT_PARAM_VM:
938 		ret = set_proto_ctx_vm(fpriv, pc, args);
939 		break;
940 
941 	case I915_CONTEXT_PARAM_ENGINES:
942 		ret = set_proto_ctx_engines(fpriv, pc, args);
943 		break;
944 
945 	case I915_CONTEXT_PARAM_PERSISTENCE:
946 		if (args->size)
947 			ret = -EINVAL;
948 		else
949 			ret = proto_context_set_persistence(fpriv->i915, pc,
950 							    args->value);
951 		break;
952 
953 	case I915_CONTEXT_PARAM_PROTECTED_CONTENT:
954 		ret = proto_context_set_protected(fpriv->i915, pc,
955 						  args->value);
956 		break;
957 
958 	case I915_CONTEXT_PARAM_NO_ZEROMAP:
959 	case I915_CONTEXT_PARAM_BAN_PERIOD:
960 	case I915_CONTEXT_PARAM_RINGSIZE:
961 	case I915_CONTEXT_PARAM_CONTEXT_IMAGE:
962 	default:
963 		ret = -EINVAL;
964 		break;
965 	}
966 
967 	return ret;
968 }
969 
970 static int intel_context_set_gem(struct intel_context *ce,
971 				 struct i915_gem_context *ctx,
972 				 struct intel_sseu sseu)
973 {
974 	int ret = 0;
975 
976 	GEM_BUG_ON(rcu_access_pointer(ce->gem_context));
977 	RCU_INIT_POINTER(ce->gem_context, ctx);
978 
979 	GEM_BUG_ON(intel_context_is_pinned(ce));
980 
981 	if (ce->engine->class == COMPUTE_CLASS)
982 		ce->ring_size = SZ_512K;
983 	else
984 		ce->ring_size = SZ_16K;
985 
986 	i915_vm_put(ce->vm);
987 	ce->vm = i915_gem_context_get_eb_vm(ctx);
988 
989 	if (ctx->sched.priority >= I915_PRIORITY_NORMAL &&
990 	    intel_engine_has_timeslices(ce->engine) &&
991 	    intel_engine_has_semaphores(ce->engine))
992 		__set_bit(CONTEXT_USE_SEMAPHORES, &ce->flags);
993 
994 	if (CONFIG_DRM_I915_REQUEST_TIMEOUT &&
995 	    ctx->i915->params.request_timeout_ms) {
996 		unsigned int timeout_ms = ctx->i915->params.request_timeout_ms;
997 
998 		intel_context_set_watchdog_us(ce, (u64)timeout_ms * 1000);
999 	}
1000 
1001 	/* A valid SSEU has no zero fields */
1002 	if (sseu.slice_mask && !WARN_ON(ce->engine->class != RENDER_CLASS))
1003 		ret = intel_context_reconfigure_sseu(ce, sseu);
1004 
1005 	if (test_bit(UCONTEXT_LOW_LATENCY, &ctx->user_flags))
1006 		__set_bit(CONTEXT_LOW_LATENCY, &ce->flags);
1007 
1008 	return ret;
1009 }
1010 
1011 static void __unpin_engines(struct i915_gem_engines *e, unsigned int count)
1012 {
1013 	while (count--) {
1014 		struct intel_context *ce = e->engines[count], *child;
1015 
1016 		if (!ce || !test_bit(CONTEXT_PERMA_PIN, &ce->flags))
1017 			continue;
1018 
1019 		for_each_child(ce, child)
1020 			intel_context_unpin(child);
1021 		intel_context_unpin(ce);
1022 	}
1023 }
1024 
1025 static void unpin_engines(struct i915_gem_engines *e)
1026 {
1027 	__unpin_engines(e, e->num_engines);
1028 }
1029 
1030 static void __free_engines(struct i915_gem_engines *e, unsigned int count)
1031 {
1032 	while (count--) {
1033 		if (!e->engines[count])
1034 			continue;
1035 
1036 		intel_context_put(e->engines[count]);
1037 	}
1038 	kfree(e);
1039 }
1040 
1041 static void free_engines(struct i915_gem_engines *e)
1042 {
1043 	__free_engines(e, e->num_engines);
1044 }
1045 
1046 static void free_engines_rcu(struct rcu_head *rcu)
1047 {
1048 	struct i915_gem_engines *engines =
1049 		container_of(rcu, struct i915_gem_engines, rcu);
1050 
1051 	i915_sw_fence_fini(&engines->fence);
1052 	free_engines(engines);
1053 }
1054 
1055 static void accumulate_runtime(struct i915_drm_client *client,
1056 			       struct i915_gem_engines *engines)
1057 {
1058 	struct i915_gem_engines_iter it;
1059 	struct intel_context *ce;
1060 
1061 	if (!client)
1062 		return;
1063 
1064 	/* Transfer accumulated runtime to the parent GEM context. */
1065 	for_each_gem_engine(ce, engines, it) {
1066 		unsigned int class = ce->engine->uabi_class;
1067 
1068 		GEM_BUG_ON(class >= ARRAY_SIZE(client->past_runtime));
1069 		atomic64_add(intel_context_get_total_runtime_ns(ce),
1070 			     &client->past_runtime[class]);
1071 	}
1072 }
1073 
1074 static int
1075 engines_notify(struct i915_sw_fence *fence, enum i915_sw_fence_notify state)
1076 {
1077 	struct i915_gem_engines *engines =
1078 		container_of(fence, typeof(*engines), fence);
1079 	struct i915_gem_context *ctx = engines->ctx;
1080 
1081 	switch (state) {
1082 	case FENCE_COMPLETE:
1083 		if (!list_empty(&engines->link)) {
1084 			unsigned long flags;
1085 
1086 			spin_lock_irqsave(&ctx->stale.lock, flags);
1087 			list_del(&engines->link);
1088 			spin_unlock_irqrestore(&ctx->stale.lock, flags);
1089 		}
1090 		accumulate_runtime(ctx->client, engines);
1091 		i915_gem_context_put(ctx);
1092 
1093 		break;
1094 
1095 	case FENCE_FREE:
1096 		init_rcu_head(&engines->rcu);
1097 		call_rcu(&engines->rcu, free_engines_rcu);
1098 		break;
1099 	}
1100 
1101 	return NOTIFY_DONE;
1102 }
1103 
1104 static struct i915_gem_engines *alloc_engines(unsigned int count)
1105 {
1106 	struct i915_gem_engines *e;
1107 
1108 	e = kzalloc(struct_size(e, engines, count), GFP_KERNEL);
1109 	if (!e)
1110 		return NULL;
1111 
1112 	i915_sw_fence_init(&e->fence, engines_notify);
1113 	return e;
1114 }
1115 
1116 static struct i915_gem_engines *default_engines(struct i915_gem_context *ctx,
1117 						struct intel_sseu rcs_sseu)
1118 {
1119 	const unsigned int max = I915_NUM_ENGINES;
1120 	struct intel_engine_cs *engine;
1121 	struct i915_gem_engines *e, *err;
1122 
1123 	e = alloc_engines(max);
1124 	if (!e)
1125 		return ERR_PTR(-ENOMEM);
1126 
1127 	for_each_uabi_engine(engine, ctx->i915) {
1128 		struct intel_context *ce;
1129 		struct intel_sseu sseu = {};
1130 		int ret;
1131 
1132 		if (engine->legacy_idx == INVALID_ENGINE)
1133 			continue;
1134 
1135 		GEM_BUG_ON(engine->legacy_idx >= max);
1136 		GEM_BUG_ON(e->engines[engine->legacy_idx]);
1137 
1138 		ce = intel_context_create(engine);
1139 		if (IS_ERR(ce)) {
1140 			err = ERR_CAST(ce);
1141 			goto free_engines;
1142 		}
1143 
1144 		e->engines[engine->legacy_idx] = ce;
1145 		e->num_engines = max(e->num_engines, engine->legacy_idx + 1);
1146 
1147 		if (engine->class == RENDER_CLASS)
1148 			sseu = rcs_sseu;
1149 
1150 		ret = intel_context_set_gem(ce, ctx, sseu);
1151 		if (ret) {
1152 			err = ERR_PTR(ret);
1153 			goto free_engines;
1154 		}
1155 
1156 	}
1157 
1158 	return e;
1159 
1160 free_engines:
1161 	free_engines(e);
1162 	return err;
1163 }
1164 
1165 static int perma_pin_contexts(struct intel_context *ce)
1166 {
1167 	struct intel_context *child;
1168 	int i = 0, j = 0, ret;
1169 
1170 	GEM_BUG_ON(!intel_context_is_parent(ce));
1171 
1172 	ret = intel_context_pin(ce);
1173 	if (unlikely(ret))
1174 		return ret;
1175 
1176 	for_each_child(ce, child) {
1177 		ret = intel_context_pin(child);
1178 		if (unlikely(ret))
1179 			goto unwind;
1180 		++i;
1181 	}
1182 
1183 	set_bit(CONTEXT_PERMA_PIN, &ce->flags);
1184 
1185 	return 0;
1186 
1187 unwind:
1188 	intel_context_unpin(ce);
1189 	for_each_child(ce, child) {
1190 		if (j++ < i)
1191 			intel_context_unpin(child);
1192 		else
1193 			break;
1194 	}
1195 
1196 	return ret;
1197 }
1198 
1199 static struct i915_gem_engines *user_engines(struct i915_gem_context *ctx,
1200 					     unsigned int num_engines,
1201 					     struct i915_gem_proto_engine *pe)
1202 {
1203 	struct i915_gem_engines *e, *err;
1204 	unsigned int n;
1205 
1206 	e = alloc_engines(num_engines);
1207 	if (!e)
1208 		return ERR_PTR(-ENOMEM);
1209 	e->num_engines = num_engines;
1210 
1211 	for (n = 0; n < num_engines; n++) {
1212 		struct intel_context *ce, *child;
1213 		int ret;
1214 
1215 		switch (pe[n].type) {
1216 		case I915_GEM_ENGINE_TYPE_PHYSICAL:
1217 			ce = intel_context_create(pe[n].engine);
1218 			break;
1219 
1220 		case I915_GEM_ENGINE_TYPE_BALANCED:
1221 			ce = intel_engine_create_virtual(pe[n].siblings,
1222 							 pe[n].num_siblings, 0);
1223 			break;
1224 
1225 		case I915_GEM_ENGINE_TYPE_PARALLEL:
1226 			ce = intel_engine_create_parallel(pe[n].siblings,
1227 							  pe[n].num_siblings,
1228 							  pe[n].width);
1229 			break;
1230 
1231 		case I915_GEM_ENGINE_TYPE_INVALID:
1232 		default:
1233 			GEM_WARN_ON(pe[n].type != I915_GEM_ENGINE_TYPE_INVALID);
1234 			continue;
1235 		}
1236 
1237 		if (IS_ERR(ce)) {
1238 			err = ERR_CAST(ce);
1239 			goto free_engines;
1240 		}
1241 
1242 		e->engines[n] = ce;
1243 
1244 		ret = intel_context_set_gem(ce, ctx, pe->sseu);
1245 		if (ret) {
1246 			err = ERR_PTR(ret);
1247 			goto free_engines;
1248 		}
1249 		for_each_child(ce, child) {
1250 			ret = intel_context_set_gem(child, ctx, pe->sseu);
1251 			if (ret) {
1252 				err = ERR_PTR(ret);
1253 				goto free_engines;
1254 			}
1255 		}
1256 
1257 		/*
1258 		 * XXX: Must be done after calling intel_context_set_gem as that
1259 		 * function changes the ring size. The ring is allocated when
1260 		 * the context is pinned. If the ring size is changed after
1261 		 * allocation we have a mismatch of the ring size and will cause
1262 		 * the context to hang. Presumably with a bit of reordering we
1263 		 * could move the perma-pin step to the backend function
1264 		 * intel_engine_create_parallel.
1265 		 */
1266 		if (pe[n].type == I915_GEM_ENGINE_TYPE_PARALLEL) {
1267 			ret = perma_pin_contexts(ce);
1268 			if (ret) {
1269 				err = ERR_PTR(ret);
1270 				goto free_engines;
1271 			}
1272 		}
1273 	}
1274 
1275 	return e;
1276 
1277 free_engines:
1278 	free_engines(e);
1279 	return err;
1280 }
1281 
1282 static void i915_gem_context_release_work(struct work_struct *work)
1283 {
1284 	struct i915_gem_context *ctx = container_of(work, typeof(*ctx),
1285 						    release_work);
1286 	struct i915_address_space *vm;
1287 
1288 	trace_i915_context_free(ctx);
1289 	GEM_BUG_ON(!i915_gem_context_is_closed(ctx));
1290 
1291 	spin_lock(&ctx->i915->gem.contexts.lock);
1292 	list_del(&ctx->link);
1293 	spin_unlock(&ctx->i915->gem.contexts.lock);
1294 
1295 	if (ctx->syncobj)
1296 		drm_syncobj_put(ctx->syncobj);
1297 
1298 	vm = ctx->vm;
1299 	if (vm)
1300 		i915_vm_put(vm);
1301 
1302 	if (ctx->pxp_wakeref)
1303 		intel_runtime_pm_put(&ctx->i915->runtime_pm, ctx->pxp_wakeref);
1304 
1305 	if (ctx->client)
1306 		i915_drm_client_put(ctx->client);
1307 
1308 	mutex_destroy(&ctx->engines_mutex);
1309 	mutex_destroy(&ctx->lut_mutex);
1310 
1311 	put_pid(ctx->pid);
1312 	mutex_destroy(&ctx->mutex);
1313 
1314 	kfree_rcu(ctx, rcu);
1315 }
1316 
1317 void i915_gem_context_release(struct kref *ref)
1318 {
1319 	struct i915_gem_context *ctx = container_of(ref, typeof(*ctx), ref);
1320 
1321 	queue_work(ctx->i915->wq, &ctx->release_work);
1322 }
1323 
1324 static inline struct i915_gem_engines *
1325 __context_engines_static(const struct i915_gem_context *ctx)
1326 {
1327 	return rcu_dereference_protected(ctx->engines, true);
1328 }
1329 
1330 static void __reset_context(struct i915_gem_context *ctx,
1331 			    struct intel_engine_cs *engine)
1332 {
1333 	intel_gt_handle_error(engine->gt, engine->mask, 0,
1334 			      "context closure in %s", ctx->name);
1335 }
1336 
1337 static bool __cancel_engine(struct intel_engine_cs *engine)
1338 {
1339 	/*
1340 	 * Send a "high priority pulse" down the engine to cause the
1341 	 * current request to be momentarily preempted. (If it fails to
1342 	 * be preempted, it will be reset). As we have marked our context
1343 	 * as banned, any incomplete request, including any running, will
1344 	 * be skipped following the preemption.
1345 	 *
1346 	 * If there is no hangchecking (one of the reasons why we try to
1347 	 * cancel the context) and no forced preemption, there may be no
1348 	 * means by which we reset the GPU and evict the persistent hog.
1349 	 * Ergo if we are unable to inject a preemptive pulse that can
1350 	 * kill the banned context, we fallback to doing a local reset
1351 	 * instead.
1352 	 */
1353 	return intel_engine_pulse(engine) == 0;
1354 }
1355 
1356 static struct intel_engine_cs *active_engine(struct intel_context *ce)
1357 {
1358 	struct intel_engine_cs *engine = NULL;
1359 	struct i915_request *rq;
1360 
1361 	if (intel_context_has_inflight(ce))
1362 		return intel_context_inflight(ce);
1363 
1364 	if (!ce->timeline)
1365 		return NULL;
1366 
1367 	/*
1368 	 * rq->link is only SLAB_TYPESAFE_BY_RCU, we need to hold a reference
1369 	 * to the request to prevent it being transferred to a new timeline
1370 	 * (and onto a new timeline->requests list).
1371 	 */
1372 	rcu_read_lock();
1373 	list_for_each_entry_reverse(rq, &ce->timeline->requests, link) {
1374 		bool found;
1375 
1376 		/* timeline is already completed upto this point? */
1377 		if (!i915_request_get_rcu(rq))
1378 			break;
1379 
1380 		/* Check with the backend if the request is inflight */
1381 		found = true;
1382 		if (likely(rcu_access_pointer(rq->timeline) == ce->timeline))
1383 			found = i915_request_active_engine(rq, &engine);
1384 
1385 		i915_request_put(rq);
1386 		if (found)
1387 			break;
1388 	}
1389 	rcu_read_unlock();
1390 
1391 	return engine;
1392 }
1393 
1394 static void
1395 kill_engines(struct i915_gem_engines *engines, bool exit, bool persistent)
1396 {
1397 	struct i915_gem_engines_iter it;
1398 	struct intel_context *ce;
1399 
1400 	/*
1401 	 * Map the user's engine back to the actual engines; one virtual
1402 	 * engine will be mapped to multiple engines, and using ctx->engine[]
1403 	 * the same engine may be have multiple instances in the user's map.
1404 	 * However, we only care about pending requests, so only include
1405 	 * engines on which there are incomplete requests.
1406 	 */
1407 	for_each_gem_engine(ce, engines, it) {
1408 		struct intel_engine_cs *engine;
1409 
1410 		if ((exit || !persistent) && intel_context_revoke(ce))
1411 			continue; /* Already marked. */
1412 
1413 		/*
1414 		 * Check the current active state of this context; if we
1415 		 * are currently executing on the GPU we need to evict
1416 		 * ourselves. On the other hand, if we haven't yet been
1417 		 * submitted to the GPU or if everything is complete,
1418 		 * we have nothing to do.
1419 		 */
1420 		engine = active_engine(ce);
1421 
1422 		/* First attempt to gracefully cancel the context */
1423 		if (engine && !__cancel_engine(engine) && (exit || !persistent))
1424 			/*
1425 			 * If we are unable to send a preemptive pulse to bump
1426 			 * the context from the GPU, we have to resort to a full
1427 			 * reset. We hope the collateral damage is worth it.
1428 			 */
1429 			__reset_context(engines->ctx, engine);
1430 	}
1431 }
1432 
1433 static void kill_context(struct i915_gem_context *ctx)
1434 {
1435 	struct i915_gem_engines *pos, *next;
1436 
1437 	spin_lock_irq(&ctx->stale.lock);
1438 	GEM_BUG_ON(!i915_gem_context_is_closed(ctx));
1439 	list_for_each_entry_safe(pos, next, &ctx->stale.engines, link) {
1440 		if (!i915_sw_fence_await(&pos->fence)) {
1441 			list_del_init(&pos->link);
1442 			continue;
1443 		}
1444 
1445 		spin_unlock_irq(&ctx->stale.lock);
1446 
1447 		kill_engines(pos, !ctx->i915->params.enable_hangcheck,
1448 			     i915_gem_context_is_persistent(ctx));
1449 
1450 		spin_lock_irq(&ctx->stale.lock);
1451 		GEM_BUG_ON(i915_sw_fence_signaled(&pos->fence));
1452 		list_safe_reset_next(pos, next, link);
1453 		list_del_init(&pos->link); /* decouple from FENCE_COMPLETE */
1454 
1455 		i915_sw_fence_complete(&pos->fence);
1456 	}
1457 	spin_unlock_irq(&ctx->stale.lock);
1458 }
1459 
1460 static void engines_idle_release(struct i915_gem_context *ctx,
1461 				 struct i915_gem_engines *engines)
1462 {
1463 	struct i915_gem_engines_iter it;
1464 	struct intel_context *ce;
1465 
1466 	INIT_LIST_HEAD(&engines->link);
1467 
1468 	engines->ctx = i915_gem_context_get(ctx);
1469 
1470 	for_each_gem_engine(ce, engines, it) {
1471 		int err;
1472 
1473 		/* serialises with execbuf */
1474 		intel_context_close(ce);
1475 		if (!intel_context_pin_if_active(ce))
1476 			continue;
1477 
1478 		/* Wait until context is finally scheduled out and retired */
1479 		err = i915_sw_fence_await_active(&engines->fence,
1480 						 &ce->active,
1481 						 I915_ACTIVE_AWAIT_BARRIER);
1482 		intel_context_unpin(ce);
1483 		if (err)
1484 			goto kill;
1485 	}
1486 
1487 	spin_lock_irq(&ctx->stale.lock);
1488 	if (!i915_gem_context_is_closed(ctx))
1489 		list_add_tail(&engines->link, &ctx->stale.engines);
1490 	spin_unlock_irq(&ctx->stale.lock);
1491 
1492 kill:
1493 	if (list_empty(&engines->link)) /* raced, already closed */
1494 		kill_engines(engines, true,
1495 			     i915_gem_context_is_persistent(ctx));
1496 
1497 	i915_sw_fence_commit(&engines->fence);
1498 }
1499 
1500 static void set_closed_name(struct i915_gem_context *ctx)
1501 {
1502 	char *s;
1503 
1504 	/* Replace '[]' with '<>' to indicate closed in debug prints */
1505 
1506 	s = strrchr(ctx->name, '[');
1507 	if (!s)
1508 		return;
1509 
1510 	*s = '<';
1511 
1512 	s = strchr(s + 1, ']');
1513 	if (s)
1514 		*s = '>';
1515 }
1516 
1517 static void context_close(struct i915_gem_context *ctx)
1518 {
1519 	struct i915_drm_client *client;
1520 
1521 	/* Flush any concurrent set_engines() */
1522 	mutex_lock(&ctx->engines_mutex);
1523 	unpin_engines(__context_engines_static(ctx));
1524 	engines_idle_release(ctx, rcu_replace_pointer(ctx->engines, NULL, 1));
1525 	i915_gem_context_set_closed(ctx);
1526 	mutex_unlock(&ctx->engines_mutex);
1527 
1528 	mutex_lock(&ctx->mutex);
1529 
1530 	set_closed_name(ctx);
1531 
1532 	/*
1533 	 * The LUT uses the VMA as a backpointer to unref the object,
1534 	 * so we need to clear the LUT before we close all the VMA (inside
1535 	 * the ppgtt).
1536 	 */
1537 	lut_close(ctx);
1538 
1539 	ctx->file_priv = ERR_PTR(-EBADF);
1540 
1541 	client = ctx->client;
1542 	if (client) {
1543 		spin_lock(&client->ctx_lock);
1544 		list_del_rcu(&ctx->client_link);
1545 		spin_unlock(&client->ctx_lock);
1546 	}
1547 
1548 	mutex_unlock(&ctx->mutex);
1549 
1550 	/*
1551 	 * If the user has disabled hangchecking, we can not be sure that
1552 	 * the batches will ever complete after the context is closed,
1553 	 * keeping the context and all resources pinned forever. So in this
1554 	 * case we opt to forcibly kill off all remaining requests on
1555 	 * context close.
1556 	 */
1557 	kill_context(ctx);
1558 
1559 	i915_gem_context_put(ctx);
1560 }
1561 
1562 static int __context_set_persistence(struct i915_gem_context *ctx, bool state)
1563 {
1564 	if (i915_gem_context_is_persistent(ctx) == state)
1565 		return 0;
1566 
1567 	if (state) {
1568 		/*
1569 		 * Only contexts that are short-lived [that will expire or be
1570 		 * reset] are allowed to survive past termination. We require
1571 		 * hangcheck to ensure that the persistent requests are healthy.
1572 		 */
1573 		if (!ctx->i915->params.enable_hangcheck)
1574 			return -EINVAL;
1575 
1576 		i915_gem_context_set_persistence(ctx);
1577 	} else {
1578 		/* To cancel a context we use "preempt-to-idle" */
1579 		if (!(ctx->i915->caps.scheduler & I915_SCHEDULER_CAP_PREEMPTION))
1580 			return -ENODEV;
1581 
1582 		/*
1583 		 * If the cancel fails, we then need to reset, cleanly!
1584 		 *
1585 		 * If the per-engine reset fails, all hope is lost! We resort
1586 		 * to a full GPU reset in that unlikely case, but realistically
1587 		 * if the engine could not reset, the full reset does not fare
1588 		 * much better. The damage has been done.
1589 		 *
1590 		 * However, if we cannot reset an engine by itself, we cannot
1591 		 * cleanup a hanging persistent context without causing
1592 		 * collateral damage, and we should not pretend we can by
1593 		 * exposing the interface.
1594 		 */
1595 		if (!intel_has_reset_engine(to_gt(ctx->i915)))
1596 			return -ENODEV;
1597 
1598 		i915_gem_context_clear_persistence(ctx);
1599 	}
1600 
1601 	return 0;
1602 }
1603 
1604 static struct i915_gem_context *
1605 i915_gem_create_context(struct drm_i915_private *i915,
1606 			const struct i915_gem_proto_context *pc)
1607 {
1608 	struct i915_gem_context *ctx;
1609 	struct i915_address_space *vm = NULL;
1610 	struct i915_gem_engines *e;
1611 	int err;
1612 	int i;
1613 
1614 	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
1615 	if (!ctx)
1616 		return ERR_PTR(-ENOMEM);
1617 
1618 	kref_init(&ctx->ref);
1619 	ctx->i915 = i915;
1620 	ctx->sched = pc->sched;
1621 	mutex_init(&ctx->mutex);
1622 	INIT_LIST_HEAD(&ctx->link);
1623 	INIT_WORK(&ctx->release_work, i915_gem_context_release_work);
1624 
1625 	spin_lock_init(&ctx->stale.lock);
1626 	INIT_LIST_HEAD(&ctx->stale.engines);
1627 
1628 	if (pc->vm) {
1629 		vm = i915_vm_get(pc->vm);
1630 	} else if (HAS_FULL_PPGTT(i915)) {
1631 		struct i915_ppgtt *ppgtt;
1632 
1633 		ppgtt = i915_ppgtt_create(to_gt(i915), 0);
1634 		if (IS_ERR(ppgtt)) {
1635 			drm_dbg(&i915->drm, "PPGTT setup failed (%ld)\n",
1636 				PTR_ERR(ppgtt));
1637 			err = PTR_ERR(ppgtt);
1638 			goto err_ctx;
1639 		}
1640 		ppgtt->vm.fpriv = pc->fpriv;
1641 		vm = &ppgtt->vm;
1642 	}
1643 	if (vm)
1644 		ctx->vm = vm;
1645 
1646 	/* Assign early so intel_context_set_gem can access these flags */
1647 	ctx->user_flags = pc->user_flags;
1648 
1649 	mutex_init(&ctx->engines_mutex);
1650 	if (pc->num_user_engines >= 0) {
1651 		i915_gem_context_set_user_engines(ctx);
1652 		e = user_engines(ctx, pc->num_user_engines, pc->user_engines);
1653 	} else {
1654 		i915_gem_context_clear_user_engines(ctx);
1655 		e = default_engines(ctx, pc->legacy_rcs_sseu);
1656 	}
1657 	if (IS_ERR(e)) {
1658 		err = PTR_ERR(e);
1659 		goto err_vm;
1660 	}
1661 	RCU_INIT_POINTER(ctx->engines, e);
1662 
1663 	INIT_RADIX_TREE(&ctx->handles_vma, GFP_KERNEL);
1664 	mutex_init(&ctx->lut_mutex);
1665 
1666 	/* NB: Mark all slices as needing a remap so that when the context first
1667 	 * loads it will restore whatever remap state already exists. If there
1668 	 * is no remap info, it will be a NOP. */
1669 	ctx->remap_slice = ALL_L3_SLICES(i915);
1670 
1671 	for (i = 0; i < ARRAY_SIZE(ctx->hang_timestamp); i++)
1672 		ctx->hang_timestamp[i] = jiffies - CONTEXT_FAST_HANG_JIFFIES;
1673 
1674 	if (pc->single_timeline) {
1675 		err = drm_syncobj_create(&ctx->syncobj,
1676 					 DRM_SYNCOBJ_CREATE_SIGNALED,
1677 					 NULL);
1678 		if (err)
1679 			goto err_engines;
1680 	}
1681 
1682 	if (pc->uses_protected_content) {
1683 		ctx->pxp_wakeref = intel_runtime_pm_get(&i915->runtime_pm);
1684 		ctx->uses_protected_content = true;
1685 	}
1686 
1687 	trace_i915_context_create(ctx);
1688 
1689 	return ctx;
1690 
1691 err_engines:
1692 	free_engines(e);
1693 err_vm:
1694 	if (ctx->vm)
1695 		i915_vm_put(ctx->vm);
1696 err_ctx:
1697 	kfree(ctx);
1698 	return ERR_PTR(err);
1699 }
1700 
1701 static void init_contexts(struct i915_gem_contexts *gc)
1702 {
1703 	spin_lock_init(&gc->lock);
1704 	INIT_LIST_HEAD(&gc->list);
1705 }
1706 
1707 void i915_gem_init__contexts(struct drm_i915_private *i915)
1708 {
1709 	init_contexts(&i915->gem.contexts);
1710 }
1711 
1712 /*
1713  * Note that this implicitly consumes the ctx reference, by placing
1714  * the ctx in the context_xa.
1715  */
1716 static void gem_context_register(struct i915_gem_context *ctx,
1717 				 struct drm_i915_file_private *fpriv,
1718 				 u32 id)
1719 {
1720 	struct drm_i915_private *i915 = ctx->i915;
1721 	void *old;
1722 
1723 	ctx->file_priv = fpriv;
1724 
1725 	ctx->pid = get_task_pid(current, PIDTYPE_PID);
1726 	ctx->client = i915_drm_client_get(fpriv->client);
1727 
1728 	snprintf(ctx->name, sizeof(ctx->name), "%s[%d]",
1729 		 current->comm, pid_nr(ctx->pid));
1730 
1731 	spin_lock(&ctx->client->ctx_lock);
1732 	list_add_tail_rcu(&ctx->client_link, &ctx->client->ctx_list);
1733 	spin_unlock(&ctx->client->ctx_lock);
1734 
1735 	spin_lock(&i915->gem.contexts.lock);
1736 	list_add_tail(&ctx->link, &i915->gem.contexts.list);
1737 	spin_unlock(&i915->gem.contexts.lock);
1738 
1739 	/* And finally expose ourselves to userspace via the idr */
1740 	old = xa_store(&fpriv->context_xa, id, ctx, GFP_KERNEL);
1741 	WARN_ON(old);
1742 }
1743 
1744 int i915_gem_context_open(struct drm_i915_private *i915,
1745 			  struct drm_file *file)
1746 {
1747 	struct drm_i915_file_private *file_priv = file->driver_priv;
1748 	struct i915_gem_proto_context *pc;
1749 	struct i915_gem_context *ctx;
1750 	int err;
1751 
1752 	mutex_init(&file_priv->proto_context_lock);
1753 	xa_init_flags(&file_priv->proto_context_xa, XA_FLAGS_ALLOC);
1754 
1755 	/* 0 reserved for the default context */
1756 	xa_init_flags(&file_priv->context_xa, XA_FLAGS_ALLOC1);
1757 
1758 	/* 0 reserved for invalid/unassigned ppgtt */
1759 	xa_init_flags(&file_priv->vm_xa, XA_FLAGS_ALLOC1);
1760 
1761 	pc = proto_context_create(file_priv, i915, 0);
1762 	if (IS_ERR(pc)) {
1763 		err = PTR_ERR(pc);
1764 		goto err;
1765 	}
1766 
1767 	ctx = i915_gem_create_context(i915, pc);
1768 	proto_context_close(i915, pc);
1769 	if (IS_ERR(ctx)) {
1770 		err = PTR_ERR(ctx);
1771 		goto err;
1772 	}
1773 
1774 	gem_context_register(ctx, file_priv, 0);
1775 
1776 	return 0;
1777 
1778 err:
1779 	xa_destroy(&file_priv->vm_xa);
1780 	xa_destroy(&file_priv->context_xa);
1781 	xa_destroy(&file_priv->proto_context_xa);
1782 	mutex_destroy(&file_priv->proto_context_lock);
1783 	return err;
1784 }
1785 
1786 void i915_gem_context_close(struct drm_file *file)
1787 {
1788 	struct drm_i915_file_private *file_priv = file->driver_priv;
1789 	struct i915_gem_proto_context *pc;
1790 	struct i915_address_space *vm;
1791 	struct i915_gem_context *ctx;
1792 	unsigned long idx;
1793 
1794 	xa_for_each(&file_priv->proto_context_xa, idx, pc)
1795 		proto_context_close(file_priv->i915, pc);
1796 	xa_destroy(&file_priv->proto_context_xa);
1797 	mutex_destroy(&file_priv->proto_context_lock);
1798 
1799 	xa_for_each(&file_priv->context_xa, idx, ctx)
1800 		context_close(ctx);
1801 	xa_destroy(&file_priv->context_xa);
1802 
1803 	xa_for_each(&file_priv->vm_xa, idx, vm)
1804 		i915_vm_put(vm);
1805 	xa_destroy(&file_priv->vm_xa);
1806 }
1807 
1808 int i915_gem_vm_create_ioctl(struct drm_device *dev, void *data,
1809 			     struct drm_file *file)
1810 {
1811 	struct drm_i915_private *i915 = to_i915(dev);
1812 	struct drm_i915_gem_vm_control *args = data;
1813 	struct drm_i915_file_private *file_priv = file->driver_priv;
1814 	struct i915_ppgtt *ppgtt;
1815 	u32 id;
1816 	int err;
1817 
1818 	if (!HAS_FULL_PPGTT(i915))
1819 		return -ENODEV;
1820 
1821 	if (args->flags)
1822 		return -EINVAL;
1823 
1824 	ppgtt = i915_ppgtt_create(to_gt(i915), 0);
1825 	if (IS_ERR(ppgtt))
1826 		return PTR_ERR(ppgtt);
1827 
1828 	if (args->extensions) {
1829 		err = i915_user_extensions(u64_to_user_ptr(args->extensions),
1830 					   NULL, 0,
1831 					   ppgtt);
1832 		if (err)
1833 			goto err_put;
1834 	}
1835 
1836 	err = xa_alloc(&file_priv->vm_xa, &id, &ppgtt->vm,
1837 		       xa_limit_32b, GFP_KERNEL);
1838 	if (err)
1839 		goto err_put;
1840 
1841 	GEM_BUG_ON(id == 0); /* reserved for invalid/unassigned ppgtt */
1842 	args->vm_id = id;
1843 	ppgtt->vm.fpriv = file_priv;
1844 	return 0;
1845 
1846 err_put:
1847 	i915_vm_put(&ppgtt->vm);
1848 	return err;
1849 }
1850 
1851 int i915_gem_vm_destroy_ioctl(struct drm_device *dev, void *data,
1852 			      struct drm_file *file)
1853 {
1854 	struct drm_i915_file_private *file_priv = file->driver_priv;
1855 	struct drm_i915_gem_vm_control *args = data;
1856 	struct i915_address_space *vm;
1857 
1858 	if (args->flags)
1859 		return -EINVAL;
1860 
1861 	if (args->extensions)
1862 		return -EINVAL;
1863 
1864 	vm = xa_erase(&file_priv->vm_xa, args->vm_id);
1865 	if (!vm)
1866 		return -ENOENT;
1867 
1868 	i915_vm_put(vm);
1869 	return 0;
1870 }
1871 
1872 static int get_ppgtt(struct drm_i915_file_private *file_priv,
1873 		     struct i915_gem_context *ctx,
1874 		     struct drm_i915_gem_context_param *args)
1875 {
1876 	struct i915_address_space *vm;
1877 	int err;
1878 	u32 id;
1879 
1880 	if (!i915_gem_context_has_full_ppgtt(ctx))
1881 		return -ENODEV;
1882 
1883 	vm = ctx->vm;
1884 	GEM_BUG_ON(!vm);
1885 
1886 	/*
1887 	 * Get a reference for the allocated handle.  Once the handle is
1888 	 * visible in the vm_xa table, userspace could try to close it
1889 	 * from under our feet, so we need to hold the extra reference
1890 	 * first.
1891 	 */
1892 	i915_vm_get(vm);
1893 
1894 	err = xa_alloc(&file_priv->vm_xa, &id, vm, xa_limit_32b, GFP_KERNEL);
1895 	if (err) {
1896 		i915_vm_put(vm);
1897 		return err;
1898 	}
1899 
1900 	GEM_BUG_ON(id == 0); /* reserved for invalid/unassigned ppgtt */
1901 	args->value = id;
1902 	args->size = 0;
1903 
1904 	return err;
1905 }
1906 
1907 int
1908 i915_gem_user_to_context_sseu(struct intel_gt *gt,
1909 			      const struct drm_i915_gem_context_param_sseu *user,
1910 			      struct intel_sseu *context)
1911 {
1912 	const struct sseu_dev_info *device = &gt->info.sseu;
1913 	struct drm_i915_private *i915 = gt->i915;
1914 	unsigned int dev_subslice_mask = intel_sseu_get_hsw_subslices(device, 0);
1915 
1916 	/* No zeros in any field. */
1917 	if (!user->slice_mask || !user->subslice_mask ||
1918 	    !user->min_eus_per_subslice || !user->max_eus_per_subslice)
1919 		return -EINVAL;
1920 
1921 	/* Max > min. */
1922 	if (user->max_eus_per_subslice < user->min_eus_per_subslice)
1923 		return -EINVAL;
1924 
1925 	/*
1926 	 * Some future proofing on the types since the uAPI is wider than the
1927 	 * current internal implementation.
1928 	 */
1929 	if (overflows_type(user->slice_mask, context->slice_mask) ||
1930 	    overflows_type(user->subslice_mask, context->subslice_mask) ||
1931 	    overflows_type(user->min_eus_per_subslice,
1932 			   context->min_eus_per_subslice) ||
1933 	    overflows_type(user->max_eus_per_subslice,
1934 			   context->max_eus_per_subslice))
1935 		return -EINVAL;
1936 
1937 	/* Check validity against hardware. */
1938 	if (user->slice_mask & ~device->slice_mask)
1939 		return -EINVAL;
1940 
1941 	if (user->subslice_mask & ~dev_subslice_mask)
1942 		return -EINVAL;
1943 
1944 	if (user->max_eus_per_subslice > device->max_eus_per_subslice)
1945 		return -EINVAL;
1946 
1947 	context->slice_mask = user->slice_mask;
1948 	context->subslice_mask = user->subslice_mask;
1949 	context->min_eus_per_subslice = user->min_eus_per_subslice;
1950 	context->max_eus_per_subslice = user->max_eus_per_subslice;
1951 
1952 	/* Part specific restrictions. */
1953 	if (GRAPHICS_VER(i915) == 11) {
1954 		unsigned int hw_s = hweight8(device->slice_mask);
1955 		unsigned int hw_ss_per_s = hweight8(dev_subslice_mask);
1956 		unsigned int req_s = hweight8(context->slice_mask);
1957 		unsigned int req_ss = hweight8(context->subslice_mask);
1958 
1959 		/*
1960 		 * Only full subslice enablement is possible if more than one
1961 		 * slice is turned on.
1962 		 */
1963 		if (req_s > 1 && req_ss != hw_ss_per_s)
1964 			return -EINVAL;
1965 
1966 		/*
1967 		 * If more than four (SScount bitfield limit) subslices are
1968 		 * requested then the number has to be even.
1969 		 */
1970 		if (req_ss > 4 && (req_ss & 1))
1971 			return -EINVAL;
1972 
1973 		/*
1974 		 * If only one slice is enabled and subslice count is below the
1975 		 * device full enablement, it must be at most half of the all
1976 		 * available subslices.
1977 		 */
1978 		if (req_s == 1 && req_ss < hw_ss_per_s &&
1979 		    req_ss > (hw_ss_per_s / 2))
1980 			return -EINVAL;
1981 
1982 		/* ABI restriction - VME use case only. */
1983 
1984 		/* All slices or one slice only. */
1985 		if (req_s != 1 && req_s != hw_s)
1986 			return -EINVAL;
1987 
1988 		/*
1989 		 * Half subslices or full enablement only when one slice is
1990 		 * enabled.
1991 		 */
1992 		if (req_s == 1 &&
1993 		    (req_ss != hw_ss_per_s && req_ss != (hw_ss_per_s / 2)))
1994 			return -EINVAL;
1995 
1996 		/* No EU configuration changes. */
1997 		if ((user->min_eus_per_subslice !=
1998 		     device->max_eus_per_subslice) ||
1999 		    (user->max_eus_per_subslice !=
2000 		     device->max_eus_per_subslice))
2001 			return -EINVAL;
2002 	}
2003 
2004 	return 0;
2005 }
2006 
2007 static int set_sseu(struct i915_gem_context *ctx,
2008 		    struct drm_i915_gem_context_param *args)
2009 {
2010 	struct drm_i915_private *i915 = ctx->i915;
2011 	struct drm_i915_gem_context_param_sseu user_sseu;
2012 	struct intel_context *ce;
2013 	struct intel_sseu sseu;
2014 	unsigned long lookup;
2015 	int ret;
2016 
2017 	if (args->size < sizeof(user_sseu))
2018 		return -EINVAL;
2019 
2020 	if (GRAPHICS_VER(i915) != 11)
2021 		return -ENODEV;
2022 
2023 	if (copy_from_user(&user_sseu, u64_to_user_ptr(args->value),
2024 			   sizeof(user_sseu)))
2025 		return -EFAULT;
2026 
2027 	if (user_sseu.rsvd)
2028 		return -EINVAL;
2029 
2030 	if (user_sseu.flags & ~(I915_CONTEXT_SSEU_FLAG_ENGINE_INDEX))
2031 		return -EINVAL;
2032 
2033 	lookup = 0;
2034 	if (user_sseu.flags & I915_CONTEXT_SSEU_FLAG_ENGINE_INDEX)
2035 		lookup |= LOOKUP_USER_INDEX;
2036 
2037 	ce = lookup_user_engine(ctx, lookup, &user_sseu.engine);
2038 	if (IS_ERR(ce))
2039 		return PTR_ERR(ce);
2040 
2041 	/* Only render engine supports RPCS configuration. */
2042 	if (ce->engine->class != RENDER_CLASS) {
2043 		ret = -ENODEV;
2044 		goto out_ce;
2045 	}
2046 
2047 	ret = i915_gem_user_to_context_sseu(ce->engine->gt, &user_sseu, &sseu);
2048 	if (ret)
2049 		goto out_ce;
2050 
2051 	ret = intel_context_reconfigure_sseu(ce, sseu);
2052 	if (ret)
2053 		goto out_ce;
2054 
2055 	args->size = sizeof(user_sseu);
2056 
2057 out_ce:
2058 	intel_context_put(ce);
2059 	return ret;
2060 }
2061 
2062 static int
2063 set_persistence(struct i915_gem_context *ctx,
2064 		const struct drm_i915_gem_context_param *args)
2065 {
2066 	if (args->size)
2067 		return -EINVAL;
2068 
2069 	return __context_set_persistence(ctx, args->value);
2070 }
2071 
2072 static int set_priority(struct i915_gem_context *ctx,
2073 			const struct drm_i915_gem_context_param *args)
2074 {
2075 	struct i915_gem_engines_iter it;
2076 	struct intel_context *ce;
2077 	int err;
2078 
2079 	err = validate_priority(ctx->i915, args);
2080 	if (err)
2081 		return err;
2082 
2083 	ctx->sched.priority = args->value;
2084 
2085 	for_each_gem_engine(ce, i915_gem_context_lock_engines(ctx), it) {
2086 		if (!intel_engine_has_timeslices(ce->engine))
2087 			continue;
2088 
2089 		if (ctx->sched.priority >= I915_PRIORITY_NORMAL &&
2090 		    intel_engine_has_semaphores(ce->engine))
2091 			intel_context_set_use_semaphores(ce);
2092 		else
2093 			intel_context_clear_use_semaphores(ce);
2094 	}
2095 	i915_gem_context_unlock_engines(ctx);
2096 
2097 	return 0;
2098 }
2099 
2100 static int get_protected(struct i915_gem_context *ctx,
2101 			 struct drm_i915_gem_context_param *args)
2102 {
2103 	args->size = 0;
2104 	args->value = i915_gem_context_uses_protected_content(ctx);
2105 
2106 	return 0;
2107 }
2108 
2109 static int set_context_image(struct i915_gem_context *ctx,
2110 			     struct drm_i915_gem_context_param *args)
2111 {
2112 	struct i915_gem_context_param_context_image user;
2113 	struct intel_context *ce;
2114 	struct file *shmem_state;
2115 	unsigned long lookup;
2116 	void *state;
2117 	int ret = 0;
2118 
2119 	if (!IS_ENABLED(CONFIG_DRM_I915_REPLAY_GPU_HANGS_API))
2120 		return -EINVAL;
2121 
2122 	if (!ctx->i915->params.enable_debug_only_api)
2123 		return -EINVAL;
2124 
2125 	if (args->size < sizeof(user))
2126 		return -EINVAL;
2127 
2128 	if (copy_from_user(&user, u64_to_user_ptr(args->value), sizeof(user)))
2129 		return -EFAULT;
2130 
2131 	if (user.mbz)
2132 		return -EINVAL;
2133 
2134 	if (user.flags & ~(I915_CONTEXT_IMAGE_FLAG_ENGINE_INDEX))
2135 		return -EINVAL;
2136 
2137 	lookup = 0;
2138 	if (user.flags & I915_CONTEXT_IMAGE_FLAG_ENGINE_INDEX)
2139 		lookup |= LOOKUP_USER_INDEX;
2140 
2141 	ce = lookup_user_engine(ctx, lookup, &user.engine);
2142 	if (IS_ERR(ce))
2143 		return PTR_ERR(ce);
2144 
2145 	if (user.size < ce->engine->context_size) {
2146 		ret = -EINVAL;
2147 		goto out_ce;
2148 	}
2149 
2150 	if (drm_WARN_ON_ONCE(&ctx->i915->drm,
2151 			     test_bit(CONTEXT_ALLOC_BIT, &ce->flags))) {
2152 		/*
2153 		 * This is racy but for a debug only API, if userspace is keen
2154 		 * to create and configure contexts, while simultaneously using
2155 		 * them from a second thread, let them suffer by potentially not
2156 		 * executing with the context image they just raced to apply.
2157 		 */
2158 		ret = -EBUSY;
2159 		goto out_ce;
2160 	}
2161 
2162 	state = memdup_user(u64_to_user_ptr(user.image), ce->engine->context_size);
2163 	if (IS_ERR(state)) {
2164 		ret = PTR_ERR(state);
2165 		goto out_ce;
2166 	}
2167 
2168 	shmem_state = shmem_create_from_data(ce->engine->name,
2169 					     state, ce->engine->context_size);
2170 	if (IS_ERR(shmem_state)) {
2171 		ret = PTR_ERR(shmem_state);
2172 		goto out_state;
2173 	}
2174 
2175 	if (intel_context_set_own_state(ce)) {
2176 		ret = -EBUSY;
2177 		fput(shmem_state);
2178 		goto out_state;
2179 	}
2180 
2181 	ce->default_state = shmem_state;
2182 
2183 	args->size = sizeof(user);
2184 
2185 out_state:
2186 	kfree(state);
2187 out_ce:
2188 	intel_context_put(ce);
2189 	return ret;
2190 }
2191 
2192 static int ctx_setparam(struct drm_i915_file_private *fpriv,
2193 			struct i915_gem_context *ctx,
2194 			struct drm_i915_gem_context_param *args)
2195 {
2196 	int ret = 0;
2197 
2198 	switch (args->param) {
2199 	case I915_CONTEXT_PARAM_NO_ERROR_CAPTURE:
2200 		if (args->size)
2201 			ret = -EINVAL;
2202 		else if (args->value)
2203 			i915_gem_context_set_no_error_capture(ctx);
2204 		else
2205 			i915_gem_context_clear_no_error_capture(ctx);
2206 		break;
2207 
2208 	case I915_CONTEXT_PARAM_BANNABLE:
2209 		if (args->size)
2210 			ret = -EINVAL;
2211 		else if (!capable(CAP_SYS_ADMIN) && !args->value)
2212 			ret = -EPERM;
2213 		else if (args->value)
2214 			i915_gem_context_set_bannable(ctx);
2215 		else if (i915_gem_context_uses_protected_content(ctx))
2216 			ret = -EPERM; /* can't clear this for protected contexts */
2217 		else
2218 			i915_gem_context_clear_bannable(ctx);
2219 		break;
2220 
2221 	case I915_CONTEXT_PARAM_RECOVERABLE:
2222 		if (args->size)
2223 			ret = -EINVAL;
2224 		else if (!args->value)
2225 			i915_gem_context_clear_recoverable(ctx);
2226 		else if (i915_gem_context_uses_protected_content(ctx))
2227 			ret = -EPERM; /* can't set this for protected contexts */
2228 		else
2229 			i915_gem_context_set_recoverable(ctx);
2230 		break;
2231 
2232 	case I915_CONTEXT_PARAM_PRIORITY:
2233 		ret = set_priority(ctx, args);
2234 		break;
2235 
2236 	case I915_CONTEXT_PARAM_SSEU:
2237 		ret = set_sseu(ctx, args);
2238 		break;
2239 
2240 	case I915_CONTEXT_PARAM_PERSISTENCE:
2241 		ret = set_persistence(ctx, args);
2242 		break;
2243 
2244 	case I915_CONTEXT_PARAM_CONTEXT_IMAGE:
2245 		ret = set_context_image(ctx, args);
2246 		break;
2247 
2248 	case I915_CONTEXT_PARAM_PROTECTED_CONTENT:
2249 	case I915_CONTEXT_PARAM_NO_ZEROMAP:
2250 	case I915_CONTEXT_PARAM_BAN_PERIOD:
2251 	case I915_CONTEXT_PARAM_RINGSIZE:
2252 	case I915_CONTEXT_PARAM_VM:
2253 	case I915_CONTEXT_PARAM_ENGINES:
2254 	default:
2255 		ret = -EINVAL;
2256 		break;
2257 	}
2258 
2259 	return ret;
2260 }
2261 
2262 struct create_ext {
2263 	struct i915_gem_proto_context *pc;
2264 	struct drm_i915_file_private *fpriv;
2265 };
2266 
2267 static int create_setparam(struct i915_user_extension __user *ext, void *data)
2268 {
2269 	struct drm_i915_gem_context_create_ext_setparam local;
2270 	const struct create_ext *arg = data;
2271 
2272 	if (copy_from_user(&local, ext, sizeof(local)))
2273 		return -EFAULT;
2274 
2275 	if (local.param.ctx_id)
2276 		return -EINVAL;
2277 
2278 	return set_proto_ctx_param(arg->fpriv, arg->pc, &local.param);
2279 }
2280 
2281 static int invalid_ext(struct i915_user_extension __user *ext, void *data)
2282 {
2283 	return -EINVAL;
2284 }
2285 
2286 static const i915_user_extension_fn create_extensions[] = {
2287 	[I915_CONTEXT_CREATE_EXT_SETPARAM] = create_setparam,
2288 	[I915_CONTEXT_CREATE_EXT_CLONE] = invalid_ext,
2289 };
2290 
2291 static bool client_is_banned(struct drm_i915_file_private *file_priv)
2292 {
2293 	return atomic_read(&file_priv->ban_score) >= I915_CLIENT_SCORE_BANNED;
2294 }
2295 
2296 static inline struct i915_gem_context *
2297 __context_lookup(struct drm_i915_file_private *file_priv, u32 id)
2298 {
2299 	struct i915_gem_context *ctx;
2300 
2301 	rcu_read_lock();
2302 	ctx = xa_load(&file_priv->context_xa, id);
2303 	if (ctx && !kref_get_unless_zero(&ctx->ref))
2304 		ctx = NULL;
2305 	rcu_read_unlock();
2306 
2307 	return ctx;
2308 }
2309 
2310 static struct i915_gem_context *
2311 finalize_create_context_locked(struct drm_i915_file_private *file_priv,
2312 			       struct i915_gem_proto_context *pc, u32 id)
2313 {
2314 	struct i915_gem_context *ctx;
2315 	void *old;
2316 
2317 	lockdep_assert_held(&file_priv->proto_context_lock);
2318 
2319 	ctx = i915_gem_create_context(file_priv->i915, pc);
2320 	if (IS_ERR(ctx))
2321 		return ctx;
2322 
2323 	/*
2324 	 * One for the xarray and one for the caller.  We need to grab
2325 	 * the reference *prior* to making the ctx visible to userspace
2326 	 * in gem_context_register(), as at any point after that
2327 	 * userspace can try to race us with another thread destroying
2328 	 * the context under our feet.
2329 	 */
2330 	i915_gem_context_get(ctx);
2331 
2332 	gem_context_register(ctx, file_priv, id);
2333 
2334 	old = xa_erase(&file_priv->proto_context_xa, id);
2335 	GEM_BUG_ON(old != pc);
2336 	proto_context_close(file_priv->i915, pc);
2337 
2338 	return ctx;
2339 }
2340 
2341 struct i915_gem_context *
2342 i915_gem_context_lookup(struct drm_i915_file_private *file_priv, u32 id)
2343 {
2344 	struct i915_gem_proto_context *pc;
2345 	struct i915_gem_context *ctx;
2346 
2347 	ctx = __context_lookup(file_priv, id);
2348 	if (ctx)
2349 		return ctx;
2350 
2351 	mutex_lock(&file_priv->proto_context_lock);
2352 	/* Try one more time under the lock */
2353 	ctx = __context_lookup(file_priv, id);
2354 	if (!ctx) {
2355 		pc = xa_load(&file_priv->proto_context_xa, id);
2356 		if (!pc)
2357 			ctx = ERR_PTR(-ENOENT);
2358 		else
2359 			ctx = finalize_create_context_locked(file_priv, pc, id);
2360 	}
2361 	mutex_unlock(&file_priv->proto_context_lock);
2362 
2363 	return ctx;
2364 }
2365 
2366 int i915_gem_context_create_ioctl(struct drm_device *dev, void *data,
2367 				  struct drm_file *file)
2368 {
2369 	struct drm_i915_private *i915 = to_i915(dev);
2370 	struct drm_i915_gem_context_create_ext *args = data;
2371 	struct create_ext ext_data;
2372 	int ret;
2373 	u32 id;
2374 
2375 	if (!DRIVER_CAPS(i915)->has_logical_contexts)
2376 		return -ENODEV;
2377 
2378 	if (args->flags & I915_CONTEXT_CREATE_FLAGS_UNKNOWN)
2379 		return -EINVAL;
2380 
2381 	ret = intel_gt_terminally_wedged(to_gt(i915));
2382 	if (ret)
2383 		return ret;
2384 
2385 	ext_data.fpriv = file->driver_priv;
2386 	if (client_is_banned(ext_data.fpriv)) {
2387 		drm_dbg(&i915->drm,
2388 			"client %s[%d] banned from creating ctx\n",
2389 			current->comm, task_pid_nr(current));
2390 		return -EIO;
2391 	}
2392 
2393 	ext_data.pc = proto_context_create(file->driver_priv, i915,
2394 					   args->flags);
2395 	if (IS_ERR(ext_data.pc))
2396 		return PTR_ERR(ext_data.pc);
2397 
2398 	if (args->flags & I915_CONTEXT_CREATE_FLAGS_USE_EXTENSIONS) {
2399 		ret = i915_user_extensions(u64_to_user_ptr(args->extensions),
2400 					   create_extensions,
2401 					   ARRAY_SIZE(create_extensions),
2402 					   &ext_data);
2403 		if (ret)
2404 			goto err_pc;
2405 	}
2406 
2407 	if (GRAPHICS_VER(i915) > 12) {
2408 		struct i915_gem_context *ctx;
2409 
2410 		/* Get ourselves a context ID */
2411 		ret = xa_alloc(&ext_data.fpriv->context_xa, &id, NULL,
2412 			       xa_limit_32b, GFP_KERNEL);
2413 		if (ret)
2414 			goto err_pc;
2415 
2416 		ctx = i915_gem_create_context(i915, ext_data.pc);
2417 		if (IS_ERR(ctx)) {
2418 			ret = PTR_ERR(ctx);
2419 			goto err_pc;
2420 		}
2421 
2422 		proto_context_close(i915, ext_data.pc);
2423 		gem_context_register(ctx, ext_data.fpriv, id);
2424 	} else {
2425 		ret = proto_context_register(ext_data.fpriv, ext_data.pc, &id);
2426 		if (ret < 0)
2427 			goto err_pc;
2428 	}
2429 
2430 	args->ctx_id = id;
2431 
2432 	return 0;
2433 
2434 err_pc:
2435 	proto_context_close(i915, ext_data.pc);
2436 	return ret;
2437 }
2438 
2439 int i915_gem_context_destroy_ioctl(struct drm_device *dev, void *data,
2440 				   struct drm_file *file)
2441 {
2442 	struct drm_i915_gem_context_destroy *args = data;
2443 	struct drm_i915_file_private *file_priv = file->driver_priv;
2444 	struct i915_gem_proto_context *pc;
2445 	struct i915_gem_context *ctx;
2446 
2447 	if (args->pad != 0)
2448 		return -EINVAL;
2449 
2450 	if (!args->ctx_id)
2451 		return -ENOENT;
2452 
2453 	/* We need to hold the proto-context lock here to prevent races
2454 	 * with finalize_create_context_locked().
2455 	 */
2456 	mutex_lock(&file_priv->proto_context_lock);
2457 	ctx = xa_erase(&file_priv->context_xa, args->ctx_id);
2458 	pc = xa_erase(&file_priv->proto_context_xa, args->ctx_id);
2459 	mutex_unlock(&file_priv->proto_context_lock);
2460 
2461 	if (!ctx && !pc)
2462 		return -ENOENT;
2463 	GEM_WARN_ON(ctx && pc);
2464 
2465 	if (pc)
2466 		proto_context_close(file_priv->i915, pc);
2467 
2468 	if (ctx)
2469 		context_close(ctx);
2470 
2471 	return 0;
2472 }
2473 
2474 static int get_sseu(struct i915_gem_context *ctx,
2475 		    struct drm_i915_gem_context_param *args)
2476 {
2477 	struct drm_i915_gem_context_param_sseu user_sseu;
2478 	struct intel_context *ce;
2479 	unsigned long lookup;
2480 	int err;
2481 
2482 	if (args->size == 0)
2483 		goto out;
2484 	else if (args->size < sizeof(user_sseu))
2485 		return -EINVAL;
2486 
2487 	if (copy_from_user(&user_sseu, u64_to_user_ptr(args->value),
2488 			   sizeof(user_sseu)))
2489 		return -EFAULT;
2490 
2491 	if (user_sseu.rsvd)
2492 		return -EINVAL;
2493 
2494 	if (user_sseu.flags & ~(I915_CONTEXT_SSEU_FLAG_ENGINE_INDEX))
2495 		return -EINVAL;
2496 
2497 	lookup = 0;
2498 	if (user_sseu.flags & I915_CONTEXT_SSEU_FLAG_ENGINE_INDEX)
2499 		lookup |= LOOKUP_USER_INDEX;
2500 
2501 	ce = lookup_user_engine(ctx, lookup, &user_sseu.engine);
2502 	if (IS_ERR(ce))
2503 		return PTR_ERR(ce);
2504 
2505 	err = intel_context_lock_pinned(ce); /* serialises with set_sseu */
2506 	if (err) {
2507 		intel_context_put(ce);
2508 		return err;
2509 	}
2510 
2511 	user_sseu.slice_mask = ce->sseu.slice_mask;
2512 	user_sseu.subslice_mask = ce->sseu.subslice_mask;
2513 	user_sseu.min_eus_per_subslice = ce->sseu.min_eus_per_subslice;
2514 	user_sseu.max_eus_per_subslice = ce->sseu.max_eus_per_subslice;
2515 
2516 	intel_context_unlock_pinned(ce);
2517 	intel_context_put(ce);
2518 
2519 	if (copy_to_user(u64_to_user_ptr(args->value), &user_sseu,
2520 			 sizeof(user_sseu)))
2521 		return -EFAULT;
2522 
2523 out:
2524 	args->size = sizeof(user_sseu);
2525 
2526 	return 0;
2527 }
2528 
2529 int i915_gem_context_getparam_ioctl(struct drm_device *dev, void *data,
2530 				    struct drm_file *file)
2531 {
2532 	struct drm_i915_file_private *file_priv = file->driver_priv;
2533 	struct drm_i915_gem_context_param *args = data;
2534 	struct i915_gem_context *ctx;
2535 	struct i915_address_space *vm;
2536 	int ret = 0;
2537 
2538 	ctx = i915_gem_context_lookup(file_priv, args->ctx_id);
2539 	if (IS_ERR(ctx))
2540 		return PTR_ERR(ctx);
2541 
2542 	switch (args->param) {
2543 	case I915_CONTEXT_PARAM_GTT_SIZE:
2544 		args->size = 0;
2545 		vm = i915_gem_context_get_eb_vm(ctx);
2546 		args->value = vm->total;
2547 		i915_vm_put(vm);
2548 
2549 		break;
2550 
2551 	case I915_CONTEXT_PARAM_NO_ERROR_CAPTURE:
2552 		args->size = 0;
2553 		args->value = i915_gem_context_no_error_capture(ctx);
2554 		break;
2555 
2556 	case I915_CONTEXT_PARAM_BANNABLE:
2557 		args->size = 0;
2558 		args->value = i915_gem_context_is_bannable(ctx);
2559 		break;
2560 
2561 	case I915_CONTEXT_PARAM_RECOVERABLE:
2562 		args->size = 0;
2563 		args->value = i915_gem_context_is_recoverable(ctx);
2564 		break;
2565 
2566 	case I915_CONTEXT_PARAM_PRIORITY:
2567 		args->size = 0;
2568 		args->value = ctx->sched.priority;
2569 		break;
2570 
2571 	case I915_CONTEXT_PARAM_SSEU:
2572 		ret = get_sseu(ctx, args);
2573 		break;
2574 
2575 	case I915_CONTEXT_PARAM_VM:
2576 		ret = get_ppgtt(file_priv, ctx, args);
2577 		break;
2578 
2579 	case I915_CONTEXT_PARAM_PERSISTENCE:
2580 		args->size = 0;
2581 		args->value = i915_gem_context_is_persistent(ctx);
2582 		break;
2583 
2584 	case I915_CONTEXT_PARAM_PROTECTED_CONTENT:
2585 		ret = get_protected(ctx, args);
2586 		break;
2587 
2588 	case I915_CONTEXT_PARAM_NO_ZEROMAP:
2589 	case I915_CONTEXT_PARAM_BAN_PERIOD:
2590 	case I915_CONTEXT_PARAM_ENGINES:
2591 	case I915_CONTEXT_PARAM_RINGSIZE:
2592 	case I915_CONTEXT_PARAM_CONTEXT_IMAGE:
2593 	default:
2594 		ret = -EINVAL;
2595 		break;
2596 	}
2597 
2598 	i915_gem_context_put(ctx);
2599 	return ret;
2600 }
2601 
2602 int i915_gem_context_setparam_ioctl(struct drm_device *dev, void *data,
2603 				    struct drm_file *file)
2604 {
2605 	struct drm_i915_file_private *file_priv = file->driver_priv;
2606 	struct drm_i915_gem_context_param *args = data;
2607 	struct i915_gem_proto_context *pc;
2608 	struct i915_gem_context *ctx;
2609 	int ret = 0;
2610 
2611 	mutex_lock(&file_priv->proto_context_lock);
2612 	ctx = __context_lookup(file_priv, args->ctx_id);
2613 	if (!ctx) {
2614 		pc = xa_load(&file_priv->proto_context_xa, args->ctx_id);
2615 		if (pc) {
2616 			/* Contexts should be finalized inside
2617 			 * GEM_CONTEXT_CREATE starting with graphics
2618 			 * version 13.
2619 			 */
2620 			WARN_ON(GRAPHICS_VER(file_priv->i915) > 12);
2621 			ret = set_proto_ctx_param(file_priv, pc, args);
2622 		} else {
2623 			ret = -ENOENT;
2624 		}
2625 	}
2626 	mutex_unlock(&file_priv->proto_context_lock);
2627 
2628 	if (ctx) {
2629 		ret = ctx_setparam(file_priv, ctx, args);
2630 		i915_gem_context_put(ctx);
2631 	}
2632 
2633 	return ret;
2634 }
2635 
2636 int i915_gem_context_reset_stats_ioctl(struct drm_device *dev,
2637 				       void *data, struct drm_file *file)
2638 {
2639 	struct drm_i915_private *i915 = to_i915(dev);
2640 	struct drm_i915_reset_stats *args = data;
2641 	struct i915_gem_context *ctx;
2642 
2643 	if (args->flags || args->pad)
2644 		return -EINVAL;
2645 
2646 	ctx = i915_gem_context_lookup(file->driver_priv, args->ctx_id);
2647 	if (IS_ERR(ctx))
2648 		return PTR_ERR(ctx);
2649 
2650 	/*
2651 	 * We opt for unserialised reads here. This may result in tearing
2652 	 * in the extremely unlikely event of a GPU hang on this context
2653 	 * as we are querying them. If we need that extra layer of protection,
2654 	 * we should wrap the hangstats with a seqlock.
2655 	 */
2656 
2657 	if (capable(CAP_SYS_ADMIN))
2658 		args->reset_count = i915_reset_count(&i915->gpu_error);
2659 	else
2660 		args->reset_count = 0;
2661 
2662 	args->batch_active = atomic_read(&ctx->guilty_count);
2663 	args->batch_pending = atomic_read(&ctx->active_count);
2664 
2665 	i915_gem_context_put(ctx);
2666 	return 0;
2667 }
2668 
2669 /* GEM context-engines iterator: for_each_gem_engine() */
2670 struct intel_context *
2671 i915_gem_engines_iter_next(struct i915_gem_engines_iter *it)
2672 {
2673 	const struct i915_gem_engines *e = it->engines;
2674 	struct intel_context *ctx;
2675 
2676 	if (unlikely(!e))
2677 		return NULL;
2678 
2679 	do {
2680 		if (it->idx >= e->num_engines)
2681 			return NULL;
2682 
2683 		ctx = e->engines[it->idx++];
2684 	} while (!ctx);
2685 
2686 	return ctx;
2687 }
2688 
2689 #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
2690 #include "selftests/mock_context.c"
2691 #include "selftests/i915_gem_context.c"
2692 #endif
2693 
2694 void i915_gem_context_module_exit(void)
2695 {
2696 	kmem_cache_destroy(slab_luts);
2697 }
2698 
2699 int __init i915_gem_context_module_init(void)
2700 {
2701 	slab_luts = KMEM_CACHE(i915_lut_handle, 0);
2702 	if (!slab_luts)
2703 		return -ENOMEM;
2704 
2705 	if (IS_ENABLED(CONFIG_DRM_I915_REPLAY_GPU_HANGS_API)) {
2706 		pr_notice("**************************************************************\n");
2707 		pr_notice("**     NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE     **\n");
2708 		pr_notice("**                                                          **\n");
2709 		if (i915_modparams.enable_debug_only_api)
2710 			pr_notice("** i915.enable_debug_only_api is intended to be set         **\n");
2711 		else
2712 			pr_notice("** CONFIG_DRM_I915_REPLAY_GPU_HANGS_API builds are intended **\n");
2713 		pr_notice("** for specific userspace graphics stack developers only!   **\n");
2714 		pr_notice("**                                                          **\n");
2715 		pr_notice("** If you are seeing this message please report this to the **\n");
2716 		pr_notice("** provider of your kernel build.                           **\n");
2717 		pr_notice("**                                                          **\n");
2718 		pr_notice("**     NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE     **\n");
2719 		pr_notice("**************************************************************\n");
2720 	}
2721 
2722 	return 0;
2723 }
2724