1 /*
2  * SPDX-License-Identifier: MIT
3  *
4  * Copyright © 2017 Intel Corporation
5  */
6 
7 #include <linux/prime_numbers.h>
8 
9 #include "gem/i915_gem_pm.h"
10 #include "gt/intel_engine_pm.h"
11 #include "gt/intel_gt.h"
12 #include "gt/intel_gt_requests.h"
13 #include "gt/intel_reset.h"
14 #include "i915_selftest.h"
15 
16 #include "gem/selftests/igt_gem_utils.h"
17 #include "selftests/i915_random.h"
18 #include "selftests/igt_flush_test.h"
19 #include "selftests/igt_live_test.h"
20 #include "selftests/igt_reset.h"
21 #include "selftests/igt_spinner.h"
22 #include "selftests/mock_drm.h"
23 #include "selftests/mock_gem_device.h"
24 
25 #include "huge_gem_object.h"
26 #include "igt_gem_utils.h"
27 
28 #define DW_PER_PAGE (PAGE_SIZE / sizeof(u32))
29 
30 static inline struct i915_address_space *ctx_vm(struct i915_gem_context *ctx)
31 {
32 	/* single threaded, private ctx */
33 	return rcu_dereference_protected(ctx->vm, true);
34 }
35 
36 static int live_nop_switch(void *arg)
37 {
38 	const unsigned int nctx = 1024;
39 	struct drm_i915_private *i915 = arg;
40 	struct intel_engine_cs *engine;
41 	struct i915_gem_context **ctx;
42 	struct igt_live_test t;
43 	struct file *file;
44 	unsigned long n;
45 	int err = -ENODEV;
46 
47 	/*
48 	 * Create as many contexts as we can feasibly get away with
49 	 * and check we can switch between them rapidly.
50 	 *
51 	 * Serves as very simple stress test for submission and HW switching
52 	 * between contexts.
53 	 */
54 
55 	if (!DRIVER_CAPS(i915)->has_logical_contexts)
56 		return 0;
57 
58 	file = mock_file(i915);
59 	if (IS_ERR(file))
60 		return PTR_ERR(file);
61 
62 	ctx = kcalloc(nctx, sizeof(*ctx), GFP_KERNEL);
63 	if (!ctx) {
64 		err = -ENOMEM;
65 		goto out_file;
66 	}
67 
68 	for (n = 0; n < nctx; n++) {
69 		ctx[n] = live_context(i915, file);
70 		if (IS_ERR(ctx[n])) {
71 			err = PTR_ERR(ctx[n]);
72 			goto out_file;
73 		}
74 	}
75 
76 	for_each_uabi_engine(engine, i915) {
77 		struct i915_request *rq = NULL;
78 		unsigned long end_time, prime;
79 		ktime_t times[2] = {};
80 
81 		times[0] = ktime_get_raw();
82 		for (n = 0; n < nctx; n++) {
83 			struct i915_request *this;
84 
85 			this = igt_request_alloc(ctx[n], engine);
86 			if (IS_ERR(this)) {
87 				err = PTR_ERR(this);
88 				goto out_file;
89 			}
90 			if (rq) {
91 				i915_request_await_dma_fence(this, &rq->fence);
92 				i915_request_put(rq);
93 			}
94 			rq = i915_request_get(this);
95 			i915_request_add(this);
96 		}
97 		if (i915_request_wait(rq, 0, HZ / 5) < 0) {
98 			pr_err("Failed to populated %d contexts\n", nctx);
99 			intel_gt_set_wedged(&i915->gt);
100 			i915_request_put(rq);
101 			err = -EIO;
102 			goto out_file;
103 		}
104 		i915_request_put(rq);
105 
106 		times[1] = ktime_get_raw();
107 
108 		pr_info("Populated %d contexts on %s in %lluns\n",
109 			nctx, engine->name, ktime_to_ns(times[1] - times[0]));
110 
111 		err = igt_live_test_begin(&t, i915, __func__, engine->name);
112 		if (err)
113 			goto out_file;
114 
115 		end_time = jiffies + i915_selftest.timeout_jiffies;
116 		for_each_prime_number_from(prime, 2, 8192) {
117 			times[1] = ktime_get_raw();
118 
119 			rq = NULL;
120 			for (n = 0; n < prime; n++) {
121 				struct i915_request *this;
122 
123 				this = igt_request_alloc(ctx[n % nctx], engine);
124 				if (IS_ERR(this)) {
125 					err = PTR_ERR(this);
126 					goto out_file;
127 				}
128 
129 				if (rq) { /* Force submission order */
130 					i915_request_await_dma_fence(this, &rq->fence);
131 					i915_request_put(rq);
132 				}
133 
134 				/*
135 				 * This space is left intentionally blank.
136 				 *
137 				 * We do not actually want to perform any
138 				 * action with this request, we just want
139 				 * to measure the latency in allocation
140 				 * and submission of our breadcrumbs -
141 				 * ensuring that the bare request is sufficient
142 				 * for the system to work (i.e. proper HEAD
143 				 * tracking of the rings, interrupt handling,
144 				 * etc). It also gives us the lowest bounds
145 				 * for latency.
146 				 */
147 
148 				rq = i915_request_get(this);
149 				i915_request_add(this);
150 			}
151 			GEM_BUG_ON(!rq);
152 			if (i915_request_wait(rq, 0, HZ / 5) < 0) {
153 				pr_err("Switching between %ld contexts timed out\n",
154 				       prime);
155 				intel_gt_set_wedged(&i915->gt);
156 				i915_request_put(rq);
157 				break;
158 			}
159 			i915_request_put(rq);
160 
161 			times[1] = ktime_sub(ktime_get_raw(), times[1]);
162 			if (prime == 2)
163 				times[0] = times[1];
164 
165 			if (__igt_timeout(end_time, NULL))
166 				break;
167 		}
168 
169 		err = igt_live_test_end(&t);
170 		if (err)
171 			goto out_file;
172 
173 		pr_info("Switch latencies on %s: 1 = %lluns, %lu = %lluns\n",
174 			engine->name,
175 			ktime_to_ns(times[0]),
176 			prime - 1, div64_u64(ktime_to_ns(times[1]), prime - 1));
177 	}
178 
179 out_file:
180 	fput(file);
181 	return err;
182 }
183 
184 struct parallel_switch {
185 	struct task_struct *tsk;
186 	struct intel_context *ce[2];
187 };
188 
189 static int __live_parallel_switch1(void *data)
190 {
191 	struct parallel_switch *arg = data;
192 	IGT_TIMEOUT(end_time);
193 	unsigned long count;
194 
195 	count = 0;
196 	do {
197 		struct i915_request *rq = NULL;
198 		int err, n;
199 
200 		err = 0;
201 		for (n = 0; !err && n < ARRAY_SIZE(arg->ce); n++) {
202 			struct i915_request *prev = rq;
203 
204 			rq = i915_request_create(arg->ce[n]);
205 			if (IS_ERR(rq)) {
206 				i915_request_put(prev);
207 				return PTR_ERR(rq);
208 			}
209 
210 			i915_request_get(rq);
211 			if (prev) {
212 				err = i915_request_await_dma_fence(rq, &prev->fence);
213 				i915_request_put(prev);
214 			}
215 
216 			i915_request_add(rq);
217 		}
218 		if (i915_request_wait(rq, 0, HZ / 5) < 0)
219 			err = -ETIME;
220 		i915_request_put(rq);
221 		if (err)
222 			return err;
223 
224 		count++;
225 	} while (!__igt_timeout(end_time, NULL));
226 
227 	pr_info("%s: %lu switches (sync)\n", arg->ce[0]->engine->name, count);
228 	return 0;
229 }
230 
231 static int __live_parallel_switchN(void *data)
232 {
233 	struct parallel_switch *arg = data;
234 	struct i915_request *rq = NULL;
235 	IGT_TIMEOUT(end_time);
236 	unsigned long count;
237 	int n;
238 
239 	count = 0;
240 	do {
241 		for (n = 0; n < ARRAY_SIZE(arg->ce); n++) {
242 			struct i915_request *prev = rq;
243 			int err = 0;
244 
245 			rq = i915_request_create(arg->ce[n]);
246 			if (IS_ERR(rq)) {
247 				i915_request_put(prev);
248 				return PTR_ERR(rq);
249 			}
250 
251 			i915_request_get(rq);
252 			if (prev) {
253 				err = i915_request_await_dma_fence(rq, &prev->fence);
254 				i915_request_put(prev);
255 			}
256 
257 			i915_request_add(rq);
258 			if (err) {
259 				i915_request_put(rq);
260 				return err;
261 			}
262 		}
263 
264 		count++;
265 	} while (!__igt_timeout(end_time, NULL));
266 	i915_request_put(rq);
267 
268 	pr_info("%s: %lu switches (many)\n", arg->ce[0]->engine->name, count);
269 	return 0;
270 }
271 
272 static int live_parallel_switch(void *arg)
273 {
274 	struct drm_i915_private *i915 = arg;
275 	static int (* const func[])(void *arg) = {
276 		__live_parallel_switch1,
277 		__live_parallel_switchN,
278 		NULL,
279 	};
280 	struct parallel_switch *data = NULL;
281 	struct i915_gem_engines *engines;
282 	struct i915_gem_engines_iter it;
283 	int (* const *fn)(void *arg);
284 	struct i915_gem_context *ctx;
285 	struct intel_context *ce;
286 	struct file *file;
287 	int n, m, count;
288 	int err = 0;
289 
290 	/*
291 	 * Check we can process switches on all engines simultaneously.
292 	 */
293 
294 	if (!DRIVER_CAPS(i915)->has_logical_contexts)
295 		return 0;
296 
297 	file = mock_file(i915);
298 	if (IS_ERR(file))
299 		return PTR_ERR(file);
300 
301 	ctx = live_context(i915, file);
302 	if (IS_ERR(ctx)) {
303 		err = PTR_ERR(ctx);
304 		goto out_file;
305 	}
306 
307 	engines = i915_gem_context_lock_engines(ctx);
308 	count = engines->num_engines;
309 
310 	data = kcalloc(count, sizeof(*data), GFP_KERNEL);
311 	if (!data) {
312 		i915_gem_context_unlock_engines(ctx);
313 		err = -ENOMEM;
314 		goto out_file;
315 	}
316 
317 	m = 0; /* Use the first context as our template for the engines */
318 	for_each_gem_engine(ce, engines, it) {
319 		err = intel_context_pin(ce);
320 		if (err) {
321 			i915_gem_context_unlock_engines(ctx);
322 			goto out;
323 		}
324 		data[m++].ce[0] = intel_context_get(ce);
325 	}
326 	i915_gem_context_unlock_engines(ctx);
327 
328 	/* Clone the same set of engines into the other contexts */
329 	for (n = 1; n < ARRAY_SIZE(data->ce); n++) {
330 		ctx = live_context(i915, file);
331 		if (IS_ERR(ctx)) {
332 			err = PTR_ERR(ctx);
333 			goto out;
334 		}
335 
336 		for (m = 0; m < count; m++) {
337 			if (!data[m].ce[0])
338 				continue;
339 
340 			ce = intel_context_create(data[m].ce[0]->engine);
341 			if (IS_ERR(ce))
342 				goto out;
343 
344 			err = intel_context_pin(ce);
345 			if (err) {
346 				intel_context_put(ce);
347 				goto out;
348 			}
349 
350 			data[m].ce[n] = ce;
351 		}
352 	}
353 
354 	for (fn = func; !err && *fn; fn++) {
355 		struct igt_live_test t;
356 		int n;
357 
358 		err = igt_live_test_begin(&t, i915, __func__, "");
359 		if (err)
360 			break;
361 
362 		for (n = 0; n < count; n++) {
363 			if (!data[n].ce[0])
364 				continue;
365 
366 			data[n].tsk = kthread_run(*fn, &data[n],
367 						  "igt/parallel:%s",
368 						  data[n].ce[0]->engine->name);
369 			if (IS_ERR(data[n].tsk)) {
370 				err = PTR_ERR(data[n].tsk);
371 				break;
372 			}
373 			get_task_struct(data[n].tsk);
374 		}
375 
376 		yield(); /* start all threads before we kthread_stop() */
377 
378 		for (n = 0; n < count; n++) {
379 			int status;
380 
381 			if (IS_ERR_OR_NULL(data[n].tsk))
382 				continue;
383 
384 			status = kthread_stop(data[n].tsk);
385 			if (status && !err)
386 				err = status;
387 
388 			put_task_struct(data[n].tsk);
389 			data[n].tsk = NULL;
390 		}
391 
392 		if (igt_live_test_end(&t))
393 			err = -EIO;
394 	}
395 
396 out:
397 	for (n = 0; n < count; n++) {
398 		for (m = 0; m < ARRAY_SIZE(data->ce); m++) {
399 			if (!data[n].ce[m])
400 				continue;
401 
402 			intel_context_unpin(data[n].ce[m]);
403 			intel_context_put(data[n].ce[m]);
404 		}
405 	}
406 	kfree(data);
407 out_file:
408 	fput(file);
409 	return err;
410 }
411 
412 static unsigned long real_page_count(struct drm_i915_gem_object *obj)
413 {
414 	return huge_gem_object_phys_size(obj) >> PAGE_SHIFT;
415 }
416 
417 static unsigned long fake_page_count(struct drm_i915_gem_object *obj)
418 {
419 	return huge_gem_object_dma_size(obj) >> PAGE_SHIFT;
420 }
421 
422 static int gpu_fill(struct intel_context *ce,
423 		    struct drm_i915_gem_object *obj,
424 		    unsigned int dw)
425 {
426 	struct i915_vma *vma;
427 	int err;
428 
429 	GEM_BUG_ON(obj->base.size > ce->vm->total);
430 	GEM_BUG_ON(!intel_engine_can_store_dword(ce->engine));
431 
432 	vma = i915_vma_instance(obj, ce->vm, NULL);
433 	if (IS_ERR(vma))
434 		return PTR_ERR(vma);
435 
436 	err = i915_vma_pin(vma, 0, 0, PIN_HIGH | PIN_USER);
437 	if (err)
438 		return err;
439 
440 	/*
441 	 * Within the GTT the huge objects maps every page onto
442 	 * its 1024 real pages (using phys_pfn = dma_pfn % 1024).
443 	 * We set the nth dword within the page using the nth
444 	 * mapping via the GTT - this should exercise the GTT mapping
445 	 * whilst checking that each context provides a unique view
446 	 * into the object.
447 	 */
448 	err = igt_gpu_fill_dw(ce, vma,
449 			      (dw * real_page_count(obj)) << PAGE_SHIFT |
450 			      (dw * sizeof(u32)),
451 			      real_page_count(obj),
452 			      dw);
453 	i915_vma_unpin(vma);
454 
455 	return err;
456 }
457 
458 static int cpu_fill(struct drm_i915_gem_object *obj, u32 value)
459 {
460 	const bool has_llc = HAS_LLC(to_i915(obj->base.dev));
461 	unsigned int n, m, need_flush;
462 	int err;
463 
464 	i915_gem_object_lock(obj, NULL);
465 	err = i915_gem_object_prepare_write(obj, &need_flush);
466 	if (err)
467 		goto out;
468 
469 	for (n = 0; n < real_page_count(obj); n++) {
470 		u32 *map;
471 
472 		map = kmap_atomic(i915_gem_object_get_page(obj, n));
473 		for (m = 0; m < DW_PER_PAGE; m++)
474 			map[m] = value;
475 		if (!has_llc)
476 			drm_clflush_virt_range(map, PAGE_SIZE);
477 		kunmap_atomic(map);
478 	}
479 
480 	i915_gem_object_finish_access(obj);
481 	obj->read_domains = I915_GEM_DOMAIN_GTT | I915_GEM_DOMAIN_CPU;
482 	obj->write_domain = 0;
483 out:
484 	i915_gem_object_unlock(obj);
485 	return err;
486 }
487 
488 static noinline int cpu_check(struct drm_i915_gem_object *obj,
489 			      unsigned int idx, unsigned int max)
490 {
491 	unsigned int n, m, needs_flush;
492 	int err;
493 
494 	i915_gem_object_lock(obj, NULL);
495 	err = i915_gem_object_prepare_read(obj, &needs_flush);
496 	if (err)
497 		goto out_unlock;
498 
499 	for (n = 0; n < real_page_count(obj); n++) {
500 		u32 *map;
501 
502 		map = kmap_atomic(i915_gem_object_get_page(obj, n));
503 		if (needs_flush & CLFLUSH_BEFORE)
504 			drm_clflush_virt_range(map, PAGE_SIZE);
505 
506 		for (m = 0; m < max; m++) {
507 			if (map[m] != m) {
508 				pr_err("%pS: Invalid value at object %d page %d/%ld, offset %d/%d: found %x expected %x\n",
509 				       __builtin_return_address(0), idx,
510 				       n, real_page_count(obj), m, max,
511 				       map[m], m);
512 				err = -EINVAL;
513 				goto out_unmap;
514 			}
515 		}
516 
517 		for (; m < DW_PER_PAGE; m++) {
518 			if (map[m] != STACK_MAGIC) {
519 				pr_err("%pS: Invalid value at object %d page %d, offset %d: found %x expected %x (uninitialised)\n",
520 				       __builtin_return_address(0), idx, n, m,
521 				       map[m], STACK_MAGIC);
522 				err = -EINVAL;
523 				goto out_unmap;
524 			}
525 		}
526 
527 out_unmap:
528 		kunmap_atomic(map);
529 		if (err)
530 			break;
531 	}
532 
533 	i915_gem_object_finish_access(obj);
534 out_unlock:
535 	i915_gem_object_unlock(obj);
536 	return err;
537 }
538 
539 static int file_add_object(struct file *file, struct drm_i915_gem_object *obj)
540 {
541 	int err;
542 
543 	GEM_BUG_ON(obj->base.handle_count);
544 
545 	/* tie the object to the drm_file for easy reaping */
546 	err = idr_alloc(&to_drm_file(file)->object_idr,
547 			&obj->base, 1, 0, GFP_KERNEL);
548 	if (err < 0)
549 		return err;
550 
551 	i915_gem_object_get(obj);
552 	obj->base.handle_count++;
553 	return 0;
554 }
555 
556 static struct drm_i915_gem_object *
557 create_test_object(struct i915_address_space *vm,
558 		   struct file *file,
559 		   struct list_head *objects)
560 {
561 	struct drm_i915_gem_object *obj;
562 	u64 size;
563 	int err;
564 
565 	/* Keep in GEM's good graces */
566 	intel_gt_retire_requests(vm->gt);
567 
568 	size = min(vm->total / 2, 1024ull * DW_PER_PAGE * PAGE_SIZE);
569 	size = round_down(size, DW_PER_PAGE * PAGE_SIZE);
570 
571 	obj = huge_gem_object(vm->i915, DW_PER_PAGE * PAGE_SIZE, size);
572 	if (IS_ERR(obj))
573 		return obj;
574 
575 	err = file_add_object(file, obj);
576 	i915_gem_object_put(obj);
577 	if (err)
578 		return ERR_PTR(err);
579 
580 	err = cpu_fill(obj, STACK_MAGIC);
581 	if (err) {
582 		pr_err("Failed to fill object with cpu, err=%d\n",
583 		       err);
584 		return ERR_PTR(err);
585 	}
586 
587 	list_add_tail(&obj->st_link, objects);
588 	return obj;
589 }
590 
591 static unsigned long max_dwords(struct drm_i915_gem_object *obj)
592 {
593 	unsigned long npages = fake_page_count(obj);
594 
595 	GEM_BUG_ON(!IS_ALIGNED(npages, DW_PER_PAGE));
596 	return npages / DW_PER_PAGE;
597 }
598 
599 static void throttle_release(struct i915_request **q, int count)
600 {
601 	int i;
602 
603 	for (i = 0; i < count; i++) {
604 		if (IS_ERR_OR_NULL(q[i]))
605 			continue;
606 
607 		i915_request_put(fetch_and_zero(&q[i]));
608 	}
609 }
610 
611 static int throttle(struct intel_context *ce,
612 		    struct i915_request **q, int count)
613 {
614 	int i;
615 
616 	if (!IS_ERR_OR_NULL(q[0])) {
617 		if (i915_request_wait(q[0],
618 				      I915_WAIT_INTERRUPTIBLE,
619 				      MAX_SCHEDULE_TIMEOUT) < 0)
620 			return -EINTR;
621 
622 		i915_request_put(q[0]);
623 	}
624 
625 	for (i = 0; i < count - 1; i++)
626 		q[i] = q[i + 1];
627 
628 	q[i] = intel_context_create_request(ce);
629 	if (IS_ERR(q[i]))
630 		return PTR_ERR(q[i]);
631 
632 	i915_request_get(q[i]);
633 	i915_request_add(q[i]);
634 
635 	return 0;
636 }
637 
638 static int igt_ctx_exec(void *arg)
639 {
640 	struct drm_i915_private *i915 = arg;
641 	struct intel_engine_cs *engine;
642 	int err = -ENODEV;
643 
644 	/*
645 	 * Create a few different contexts (with different mm) and write
646 	 * through each ctx/mm using the GPU making sure those writes end
647 	 * up in the expected pages of our obj.
648 	 */
649 
650 	if (!DRIVER_CAPS(i915)->has_logical_contexts)
651 		return 0;
652 
653 	for_each_uabi_engine(engine, i915) {
654 		struct drm_i915_gem_object *obj = NULL;
655 		unsigned long ncontexts, ndwords, dw;
656 		struct i915_request *tq[5] = {};
657 		struct igt_live_test t;
658 		IGT_TIMEOUT(end_time);
659 		LIST_HEAD(objects);
660 		struct file *file;
661 
662 		if (!intel_engine_can_store_dword(engine))
663 			continue;
664 
665 		if (!engine->context_size)
666 			continue; /* No logical context support in HW */
667 
668 		file = mock_file(i915);
669 		if (IS_ERR(file))
670 			return PTR_ERR(file);
671 
672 		err = igt_live_test_begin(&t, i915, __func__, engine->name);
673 		if (err)
674 			goto out_file;
675 
676 		ncontexts = 0;
677 		ndwords = 0;
678 		dw = 0;
679 		while (!time_after(jiffies, end_time)) {
680 			struct i915_gem_context *ctx;
681 			struct intel_context *ce;
682 
683 			ctx = kernel_context(i915, NULL);
684 			if (IS_ERR(ctx)) {
685 				err = PTR_ERR(ctx);
686 				goto out_file;
687 			}
688 
689 			ce = i915_gem_context_get_engine(ctx, engine->legacy_idx);
690 			GEM_BUG_ON(IS_ERR(ce));
691 
692 			if (!obj) {
693 				obj = create_test_object(ce->vm, file, &objects);
694 				if (IS_ERR(obj)) {
695 					err = PTR_ERR(obj);
696 					intel_context_put(ce);
697 					kernel_context_close(ctx);
698 					goto out_file;
699 				}
700 			}
701 
702 			err = gpu_fill(ce, obj, dw);
703 			if (err) {
704 				pr_err("Failed to fill dword %lu [%lu/%lu] with gpu (%s) [full-ppgtt? %s], err=%d\n",
705 				       ndwords, dw, max_dwords(obj),
706 				       engine->name,
707 				       yesno(!!rcu_access_pointer(ctx->vm)),
708 				       err);
709 				intel_context_put(ce);
710 				kernel_context_close(ctx);
711 				goto out_file;
712 			}
713 
714 			err = throttle(ce, tq, ARRAY_SIZE(tq));
715 			if (err) {
716 				intel_context_put(ce);
717 				kernel_context_close(ctx);
718 				goto out_file;
719 			}
720 
721 			if (++dw == max_dwords(obj)) {
722 				obj = NULL;
723 				dw = 0;
724 			}
725 
726 			ndwords++;
727 			ncontexts++;
728 
729 			intel_context_put(ce);
730 			kernel_context_close(ctx);
731 		}
732 
733 		pr_info("Submitted %lu contexts to %s, filling %lu dwords\n",
734 			ncontexts, engine->name, ndwords);
735 
736 		ncontexts = dw = 0;
737 		list_for_each_entry(obj, &objects, st_link) {
738 			unsigned int rem =
739 				min_t(unsigned int, ndwords - dw, max_dwords(obj));
740 
741 			err = cpu_check(obj, ncontexts++, rem);
742 			if (err)
743 				break;
744 
745 			dw += rem;
746 		}
747 
748 out_file:
749 		throttle_release(tq, ARRAY_SIZE(tq));
750 		if (igt_live_test_end(&t))
751 			err = -EIO;
752 
753 		fput(file);
754 		if (err)
755 			return err;
756 
757 		i915_gem_drain_freed_objects(i915);
758 	}
759 
760 	return 0;
761 }
762 
763 static int igt_shared_ctx_exec(void *arg)
764 {
765 	struct drm_i915_private *i915 = arg;
766 	struct i915_request *tq[5] = {};
767 	struct i915_gem_context *parent;
768 	struct intel_engine_cs *engine;
769 	struct igt_live_test t;
770 	struct file *file;
771 	int err = 0;
772 
773 	/*
774 	 * Create a few different contexts with the same mm and write
775 	 * through each ctx using the GPU making sure those writes end
776 	 * up in the expected pages of our obj.
777 	 */
778 	if (!DRIVER_CAPS(i915)->has_logical_contexts)
779 		return 0;
780 
781 	file = mock_file(i915);
782 	if (IS_ERR(file))
783 		return PTR_ERR(file);
784 
785 	parent = live_context(i915, file);
786 	if (IS_ERR(parent)) {
787 		err = PTR_ERR(parent);
788 		goto out_file;
789 	}
790 
791 	if (!parent->vm) { /* not full-ppgtt; nothing to share */
792 		err = 0;
793 		goto out_file;
794 	}
795 
796 	err = igt_live_test_begin(&t, i915, __func__, "");
797 	if (err)
798 		goto out_file;
799 
800 	for_each_uabi_engine(engine, i915) {
801 		unsigned long ncontexts, ndwords, dw;
802 		struct drm_i915_gem_object *obj = NULL;
803 		IGT_TIMEOUT(end_time);
804 		LIST_HEAD(objects);
805 
806 		if (!intel_engine_can_store_dword(engine))
807 			continue;
808 
809 		dw = 0;
810 		ndwords = 0;
811 		ncontexts = 0;
812 		while (!time_after(jiffies, end_time)) {
813 			struct i915_gem_context *ctx;
814 			struct intel_context *ce;
815 
816 			ctx = kernel_context(i915, ctx_vm(parent));
817 			if (IS_ERR(ctx)) {
818 				err = PTR_ERR(ctx);
819 				goto out_test;
820 			}
821 
822 			ce = i915_gem_context_get_engine(ctx, engine->legacy_idx);
823 			GEM_BUG_ON(IS_ERR(ce));
824 
825 			if (!obj) {
826 				obj = create_test_object(ctx_vm(parent),
827 							 file, &objects);
828 				if (IS_ERR(obj)) {
829 					err = PTR_ERR(obj);
830 					intel_context_put(ce);
831 					kernel_context_close(ctx);
832 					goto out_test;
833 				}
834 			}
835 
836 			err = gpu_fill(ce, obj, dw);
837 			if (err) {
838 				pr_err("Failed to fill dword %lu [%lu/%lu] with gpu (%s) [full-ppgtt? %s], err=%d\n",
839 				       ndwords, dw, max_dwords(obj),
840 				       engine->name,
841 				       yesno(!!rcu_access_pointer(ctx->vm)),
842 				       err);
843 				intel_context_put(ce);
844 				kernel_context_close(ctx);
845 				goto out_test;
846 			}
847 
848 			err = throttle(ce, tq, ARRAY_SIZE(tq));
849 			if (err) {
850 				intel_context_put(ce);
851 				kernel_context_close(ctx);
852 				goto out_test;
853 			}
854 
855 			if (++dw == max_dwords(obj)) {
856 				obj = NULL;
857 				dw = 0;
858 			}
859 
860 			ndwords++;
861 			ncontexts++;
862 
863 			intel_context_put(ce);
864 			kernel_context_close(ctx);
865 		}
866 		pr_info("Submitted %lu contexts to %s, filling %lu dwords\n",
867 			ncontexts, engine->name, ndwords);
868 
869 		ncontexts = dw = 0;
870 		list_for_each_entry(obj, &objects, st_link) {
871 			unsigned int rem =
872 				min_t(unsigned int, ndwords - dw, max_dwords(obj));
873 
874 			err = cpu_check(obj, ncontexts++, rem);
875 			if (err)
876 				goto out_test;
877 
878 			dw += rem;
879 		}
880 
881 		i915_gem_drain_freed_objects(i915);
882 	}
883 out_test:
884 	throttle_release(tq, ARRAY_SIZE(tq));
885 	if (igt_live_test_end(&t))
886 		err = -EIO;
887 out_file:
888 	fput(file);
889 	return err;
890 }
891 
892 static int rpcs_query_batch(struct drm_i915_gem_object *rpcs, struct i915_vma *vma)
893 {
894 	u32 *cmd;
895 
896 	GEM_BUG_ON(GRAPHICS_VER(vma->vm->i915) < 8);
897 
898 	cmd = i915_gem_object_pin_map(rpcs, I915_MAP_WB);
899 	if (IS_ERR(cmd))
900 		return PTR_ERR(cmd);
901 
902 	*cmd++ = MI_STORE_REGISTER_MEM_GEN8;
903 	*cmd++ = i915_mmio_reg_offset(GEN8_R_PWR_CLK_STATE);
904 	*cmd++ = lower_32_bits(vma->node.start);
905 	*cmd++ = upper_32_bits(vma->node.start);
906 	*cmd = MI_BATCH_BUFFER_END;
907 
908 	__i915_gem_object_flush_map(rpcs, 0, 64);
909 	i915_gem_object_unpin_map(rpcs);
910 
911 	intel_gt_chipset_flush(vma->vm->gt);
912 
913 	return 0;
914 }
915 
916 static int
917 emit_rpcs_query(struct drm_i915_gem_object *obj,
918 		struct intel_context *ce,
919 		struct i915_request **rq_out)
920 {
921 	struct drm_i915_private *i915 = to_i915(obj->base.dev);
922 	struct i915_request *rq;
923 	struct i915_gem_ww_ctx ww;
924 	struct i915_vma *batch;
925 	struct i915_vma *vma;
926 	struct drm_i915_gem_object *rpcs;
927 	int err;
928 
929 	GEM_BUG_ON(!intel_engine_can_store_dword(ce->engine));
930 
931 	if (GRAPHICS_VER(i915) < 8)
932 		return -EINVAL;
933 
934 	vma = i915_vma_instance(obj, ce->vm, NULL);
935 	if (IS_ERR(vma))
936 		return PTR_ERR(vma);
937 
938 	rpcs = i915_gem_object_create_internal(i915, PAGE_SIZE);
939 	if (IS_ERR(rpcs))
940 		return PTR_ERR(rpcs);
941 
942 	batch = i915_vma_instance(rpcs, ce->vm, NULL);
943 	if (IS_ERR(batch)) {
944 		err = PTR_ERR(batch);
945 		goto err_put;
946 	}
947 
948 	i915_gem_ww_ctx_init(&ww, false);
949 retry:
950 	err = i915_gem_object_lock(obj, &ww);
951 	if (!err)
952 		err = i915_gem_object_lock(rpcs, &ww);
953 	if (!err)
954 		err = i915_gem_object_set_to_gtt_domain(obj, false);
955 	if (!err)
956 		err = i915_vma_pin_ww(vma, &ww, 0, 0, PIN_USER);
957 	if (err)
958 		goto err_put;
959 
960 	err = i915_vma_pin_ww(batch, &ww, 0, 0, PIN_USER);
961 	if (err)
962 		goto err_vma;
963 
964 	err = rpcs_query_batch(rpcs, vma);
965 	if (err)
966 		goto err_batch;
967 
968 	rq = i915_request_create(ce);
969 	if (IS_ERR(rq)) {
970 		err = PTR_ERR(rq);
971 		goto err_batch;
972 	}
973 
974 	err = i915_request_await_object(rq, batch->obj, false);
975 	if (err == 0)
976 		err = i915_vma_move_to_active(batch, rq, 0);
977 	if (err)
978 		goto skip_request;
979 
980 	err = i915_request_await_object(rq, vma->obj, true);
981 	if (err == 0)
982 		err = i915_vma_move_to_active(vma, rq, EXEC_OBJECT_WRITE);
983 	if (err)
984 		goto skip_request;
985 
986 	if (rq->engine->emit_init_breadcrumb) {
987 		err = rq->engine->emit_init_breadcrumb(rq);
988 		if (err)
989 			goto skip_request;
990 	}
991 
992 	err = rq->engine->emit_bb_start(rq,
993 					batch->node.start, batch->node.size,
994 					0);
995 	if (err)
996 		goto skip_request;
997 
998 	*rq_out = i915_request_get(rq);
999 
1000 skip_request:
1001 	if (err)
1002 		i915_request_set_error_once(rq, err);
1003 	i915_request_add(rq);
1004 err_batch:
1005 	i915_vma_unpin(batch);
1006 err_vma:
1007 	i915_vma_unpin(vma);
1008 err_put:
1009 	if (err == -EDEADLK) {
1010 		err = i915_gem_ww_ctx_backoff(&ww);
1011 		if (!err)
1012 			goto retry;
1013 	}
1014 	i915_gem_ww_ctx_fini(&ww);
1015 	i915_gem_object_put(rpcs);
1016 	return err;
1017 }
1018 
1019 #define TEST_IDLE	BIT(0)
1020 #define TEST_BUSY	BIT(1)
1021 #define TEST_RESET	BIT(2)
1022 
1023 static int
1024 __sseu_prepare(const char *name,
1025 	       unsigned int flags,
1026 	       struct intel_context *ce,
1027 	       struct igt_spinner **spin)
1028 {
1029 	struct i915_request *rq;
1030 	int ret;
1031 
1032 	*spin = NULL;
1033 	if (!(flags & (TEST_BUSY | TEST_RESET)))
1034 		return 0;
1035 
1036 	*spin = kzalloc(sizeof(**spin), GFP_KERNEL);
1037 	if (!*spin)
1038 		return -ENOMEM;
1039 
1040 	ret = igt_spinner_init(*spin, ce->engine->gt);
1041 	if (ret)
1042 		goto err_free;
1043 
1044 	rq = igt_spinner_create_request(*spin, ce, MI_NOOP);
1045 	if (IS_ERR(rq)) {
1046 		ret = PTR_ERR(rq);
1047 		goto err_fini;
1048 	}
1049 
1050 	i915_request_add(rq);
1051 
1052 	if (!igt_wait_for_spinner(*spin, rq)) {
1053 		pr_err("%s: Spinner failed to start!\n", name);
1054 		ret = -ETIMEDOUT;
1055 		goto err_end;
1056 	}
1057 
1058 	return 0;
1059 
1060 err_end:
1061 	igt_spinner_end(*spin);
1062 err_fini:
1063 	igt_spinner_fini(*spin);
1064 err_free:
1065 	kfree(fetch_and_zero(spin));
1066 	return ret;
1067 }
1068 
1069 static int
1070 __read_slice_count(struct intel_context *ce,
1071 		   struct drm_i915_gem_object *obj,
1072 		   struct igt_spinner *spin,
1073 		   u32 *rpcs)
1074 {
1075 	struct i915_request *rq = NULL;
1076 	u32 s_mask, s_shift;
1077 	unsigned int cnt;
1078 	u32 *buf, val;
1079 	long ret;
1080 
1081 	ret = emit_rpcs_query(obj, ce, &rq);
1082 	if (ret)
1083 		return ret;
1084 
1085 	if (spin)
1086 		igt_spinner_end(spin);
1087 
1088 	ret = i915_request_wait(rq, 0, MAX_SCHEDULE_TIMEOUT);
1089 	i915_request_put(rq);
1090 	if (ret < 0)
1091 		return ret;
1092 
1093 	buf = i915_gem_object_pin_map_unlocked(obj, I915_MAP_WB);
1094 	if (IS_ERR(buf)) {
1095 		ret = PTR_ERR(buf);
1096 		return ret;
1097 	}
1098 
1099 	if (GRAPHICS_VER(ce->engine->i915) >= 11) {
1100 		s_mask = GEN11_RPCS_S_CNT_MASK;
1101 		s_shift = GEN11_RPCS_S_CNT_SHIFT;
1102 	} else {
1103 		s_mask = GEN8_RPCS_S_CNT_MASK;
1104 		s_shift = GEN8_RPCS_S_CNT_SHIFT;
1105 	}
1106 
1107 	val = *buf;
1108 	cnt = (val & s_mask) >> s_shift;
1109 	*rpcs = val;
1110 
1111 	i915_gem_object_unpin_map(obj);
1112 
1113 	return cnt;
1114 }
1115 
1116 static int
1117 __check_rpcs(const char *name, u32 rpcs, int slices, unsigned int expected,
1118 	     const char *prefix, const char *suffix)
1119 {
1120 	if (slices == expected)
1121 		return 0;
1122 
1123 	if (slices < 0) {
1124 		pr_err("%s: %s read slice count failed with %d%s\n",
1125 		       name, prefix, slices, suffix);
1126 		return slices;
1127 	}
1128 
1129 	pr_err("%s: %s slice count %d is not %u%s\n",
1130 	       name, prefix, slices, expected, suffix);
1131 
1132 	pr_info("RPCS=0x%x; %u%sx%u%s\n",
1133 		rpcs, slices,
1134 		(rpcs & GEN8_RPCS_S_CNT_ENABLE) ? "*" : "",
1135 		(rpcs & GEN8_RPCS_SS_CNT_MASK) >> GEN8_RPCS_SS_CNT_SHIFT,
1136 		(rpcs & GEN8_RPCS_SS_CNT_ENABLE) ? "*" : "");
1137 
1138 	return -EINVAL;
1139 }
1140 
1141 static int
1142 __sseu_finish(const char *name,
1143 	      unsigned int flags,
1144 	      struct intel_context *ce,
1145 	      struct drm_i915_gem_object *obj,
1146 	      unsigned int expected,
1147 	      struct igt_spinner *spin)
1148 {
1149 	unsigned int slices = hweight32(ce->engine->sseu.slice_mask);
1150 	u32 rpcs = 0;
1151 	int ret = 0;
1152 
1153 	if (flags & TEST_RESET) {
1154 		ret = intel_engine_reset(ce->engine, "sseu");
1155 		if (ret)
1156 			goto out;
1157 	}
1158 
1159 	ret = __read_slice_count(ce, obj,
1160 				 flags & TEST_RESET ? NULL : spin, &rpcs);
1161 	ret = __check_rpcs(name, rpcs, ret, expected, "Context", "!");
1162 	if (ret)
1163 		goto out;
1164 
1165 	ret = __read_slice_count(ce->engine->kernel_context, obj, NULL, &rpcs);
1166 	ret = __check_rpcs(name, rpcs, ret, slices, "Kernel context", "!");
1167 
1168 out:
1169 	if (spin)
1170 		igt_spinner_end(spin);
1171 
1172 	if ((flags & TEST_IDLE) && ret == 0) {
1173 		ret = igt_flush_test(ce->engine->i915);
1174 		if (ret)
1175 			return ret;
1176 
1177 		ret = __read_slice_count(ce, obj, NULL, &rpcs);
1178 		ret = __check_rpcs(name, rpcs, ret, expected,
1179 				   "Context", " after idle!");
1180 	}
1181 
1182 	return ret;
1183 }
1184 
1185 static int
1186 __sseu_test(const char *name,
1187 	    unsigned int flags,
1188 	    struct intel_context *ce,
1189 	    struct drm_i915_gem_object *obj,
1190 	    struct intel_sseu sseu)
1191 {
1192 	struct igt_spinner *spin = NULL;
1193 	int ret;
1194 
1195 	intel_engine_pm_get(ce->engine);
1196 
1197 	ret = __sseu_prepare(name, flags, ce, &spin);
1198 	if (ret)
1199 		goto out_pm;
1200 
1201 	ret = intel_context_reconfigure_sseu(ce, sseu);
1202 	if (ret)
1203 		goto out_spin;
1204 
1205 	ret = __sseu_finish(name, flags, ce, obj,
1206 			    hweight32(sseu.slice_mask), spin);
1207 
1208 out_spin:
1209 	if (spin) {
1210 		igt_spinner_end(spin);
1211 		igt_spinner_fini(spin);
1212 		kfree(spin);
1213 	}
1214 out_pm:
1215 	intel_engine_pm_put(ce->engine);
1216 	return ret;
1217 }
1218 
1219 static int
1220 __igt_ctx_sseu(struct drm_i915_private *i915,
1221 	       const char *name,
1222 	       unsigned int flags)
1223 {
1224 	struct drm_i915_gem_object *obj;
1225 	int inst = 0;
1226 	int ret = 0;
1227 
1228 	if (GRAPHICS_VER(i915) < 9)
1229 		return 0;
1230 
1231 	if (flags & TEST_RESET)
1232 		igt_global_reset_lock(&i915->gt);
1233 
1234 	obj = i915_gem_object_create_internal(i915, PAGE_SIZE);
1235 	if (IS_ERR(obj)) {
1236 		ret = PTR_ERR(obj);
1237 		goto out_unlock;
1238 	}
1239 
1240 	do {
1241 		struct intel_engine_cs *engine;
1242 		struct intel_context *ce;
1243 		struct intel_sseu pg_sseu;
1244 
1245 		engine = intel_engine_lookup_user(i915,
1246 						  I915_ENGINE_CLASS_RENDER,
1247 						  inst++);
1248 		if (!engine)
1249 			break;
1250 
1251 		if (hweight32(engine->sseu.slice_mask) < 2)
1252 			continue;
1253 
1254 		if (!engine->gt->info.sseu.has_slice_pg)
1255 			continue;
1256 
1257 		/*
1258 		 * Gen11 VME friendly power-gated configuration with
1259 		 * half enabled sub-slices.
1260 		 */
1261 		pg_sseu = engine->sseu;
1262 		pg_sseu.slice_mask = 1;
1263 		pg_sseu.subslice_mask =
1264 			~(~0 << (hweight32(engine->sseu.subslice_mask) / 2));
1265 
1266 		pr_info("%s: SSEU subtest '%s', flags=%x, def_slices=%u, pg_slices=%u\n",
1267 			engine->name, name, flags,
1268 			hweight32(engine->sseu.slice_mask),
1269 			hweight32(pg_sseu.slice_mask));
1270 
1271 		ce = intel_context_create(engine);
1272 		if (IS_ERR(ce)) {
1273 			ret = PTR_ERR(ce);
1274 			goto out_put;
1275 		}
1276 
1277 		ret = intel_context_pin(ce);
1278 		if (ret)
1279 			goto out_ce;
1280 
1281 		/* First set the default mask. */
1282 		ret = __sseu_test(name, flags, ce, obj, engine->sseu);
1283 		if (ret)
1284 			goto out_unpin;
1285 
1286 		/* Then set a power-gated configuration. */
1287 		ret = __sseu_test(name, flags, ce, obj, pg_sseu);
1288 		if (ret)
1289 			goto out_unpin;
1290 
1291 		/* Back to defaults. */
1292 		ret = __sseu_test(name, flags, ce, obj, engine->sseu);
1293 		if (ret)
1294 			goto out_unpin;
1295 
1296 		/* One last power-gated configuration for the road. */
1297 		ret = __sseu_test(name, flags, ce, obj, pg_sseu);
1298 		if (ret)
1299 			goto out_unpin;
1300 
1301 out_unpin:
1302 		intel_context_unpin(ce);
1303 out_ce:
1304 		intel_context_put(ce);
1305 	} while (!ret);
1306 
1307 	if (igt_flush_test(i915))
1308 		ret = -EIO;
1309 
1310 out_put:
1311 	i915_gem_object_put(obj);
1312 
1313 out_unlock:
1314 	if (flags & TEST_RESET)
1315 		igt_global_reset_unlock(&i915->gt);
1316 
1317 	if (ret)
1318 		pr_err("%s: Failed with %d!\n", name, ret);
1319 
1320 	return ret;
1321 }
1322 
1323 static int igt_ctx_sseu(void *arg)
1324 {
1325 	struct {
1326 		const char *name;
1327 		unsigned int flags;
1328 	} *phase, phases[] = {
1329 		{ .name = "basic", .flags = 0 },
1330 		{ .name = "idle", .flags = TEST_IDLE },
1331 		{ .name = "busy", .flags = TEST_BUSY },
1332 		{ .name = "busy-reset", .flags = TEST_BUSY | TEST_RESET },
1333 		{ .name = "busy-idle", .flags = TEST_BUSY | TEST_IDLE },
1334 		{ .name = "reset-idle", .flags = TEST_RESET | TEST_IDLE },
1335 	};
1336 	unsigned int i;
1337 	int ret = 0;
1338 
1339 	for (i = 0, phase = phases; ret == 0 && i < ARRAY_SIZE(phases);
1340 	     i++, phase++)
1341 		ret = __igt_ctx_sseu(arg, phase->name, phase->flags);
1342 
1343 	return ret;
1344 }
1345 
1346 static int igt_ctx_readonly(void *arg)
1347 {
1348 	struct drm_i915_private *i915 = arg;
1349 	unsigned long idx, ndwords, dw, num_engines;
1350 	struct drm_i915_gem_object *obj = NULL;
1351 	struct i915_request *tq[5] = {};
1352 	struct i915_gem_engines_iter it;
1353 	struct i915_address_space *vm;
1354 	struct i915_gem_context *ctx;
1355 	struct intel_context *ce;
1356 	struct igt_live_test t;
1357 	I915_RND_STATE(prng);
1358 	IGT_TIMEOUT(end_time);
1359 	LIST_HEAD(objects);
1360 	struct file *file;
1361 	int err = -ENODEV;
1362 
1363 	/*
1364 	 * Create a few read-only objects (with the occasional writable object)
1365 	 * and try to write into these object checking that the GPU discards
1366 	 * any write to a read-only object.
1367 	 */
1368 
1369 	file = mock_file(i915);
1370 	if (IS_ERR(file))
1371 		return PTR_ERR(file);
1372 
1373 	err = igt_live_test_begin(&t, i915, __func__, "");
1374 	if (err)
1375 		goto out_file;
1376 
1377 	ctx = live_context(i915, file);
1378 	if (IS_ERR(ctx)) {
1379 		err = PTR_ERR(ctx);
1380 		goto out_file;
1381 	}
1382 
1383 	vm = ctx_vm(ctx) ?: &i915->ggtt.alias->vm;
1384 	if (!vm || !vm->has_read_only) {
1385 		err = 0;
1386 		goto out_file;
1387 	}
1388 
1389 	num_engines = 0;
1390 	for_each_gem_engine(ce, i915_gem_context_lock_engines(ctx), it)
1391 		if (intel_engine_can_store_dword(ce->engine))
1392 			num_engines++;
1393 	i915_gem_context_unlock_engines(ctx);
1394 
1395 	ndwords = 0;
1396 	dw = 0;
1397 	while (!time_after(jiffies, end_time)) {
1398 		for_each_gem_engine(ce,
1399 				    i915_gem_context_lock_engines(ctx), it) {
1400 			if (!intel_engine_can_store_dword(ce->engine))
1401 				continue;
1402 
1403 			if (!obj) {
1404 				obj = create_test_object(ce->vm, file, &objects);
1405 				if (IS_ERR(obj)) {
1406 					err = PTR_ERR(obj);
1407 					i915_gem_context_unlock_engines(ctx);
1408 					goto out_file;
1409 				}
1410 
1411 				if (prandom_u32_state(&prng) & 1)
1412 					i915_gem_object_set_readonly(obj);
1413 			}
1414 
1415 			err = gpu_fill(ce, obj, dw);
1416 			if (err) {
1417 				pr_err("Failed to fill dword %lu [%lu/%lu] with gpu (%s) [full-ppgtt? %s], err=%d\n",
1418 				       ndwords, dw, max_dwords(obj),
1419 				       ce->engine->name,
1420 				       yesno(!!ctx_vm(ctx)),
1421 				       err);
1422 				i915_gem_context_unlock_engines(ctx);
1423 				goto out_file;
1424 			}
1425 
1426 			err = throttle(ce, tq, ARRAY_SIZE(tq));
1427 			if (err) {
1428 				i915_gem_context_unlock_engines(ctx);
1429 				goto out_file;
1430 			}
1431 
1432 			if (++dw == max_dwords(obj)) {
1433 				obj = NULL;
1434 				dw = 0;
1435 			}
1436 			ndwords++;
1437 		}
1438 		i915_gem_context_unlock_engines(ctx);
1439 	}
1440 	pr_info("Submitted %lu dwords (across %lu engines)\n",
1441 		ndwords, num_engines);
1442 
1443 	dw = 0;
1444 	idx = 0;
1445 	list_for_each_entry(obj, &objects, st_link) {
1446 		unsigned int rem =
1447 			min_t(unsigned int, ndwords - dw, max_dwords(obj));
1448 		unsigned int num_writes;
1449 
1450 		num_writes = rem;
1451 		if (i915_gem_object_is_readonly(obj))
1452 			num_writes = 0;
1453 
1454 		err = cpu_check(obj, idx++, num_writes);
1455 		if (err)
1456 			break;
1457 
1458 		dw += rem;
1459 	}
1460 
1461 out_file:
1462 	throttle_release(tq, ARRAY_SIZE(tq));
1463 	if (igt_live_test_end(&t))
1464 		err = -EIO;
1465 
1466 	fput(file);
1467 	return err;
1468 }
1469 
1470 static int check_scratch(struct i915_address_space *vm, u64 offset)
1471 {
1472 	struct drm_mm_node *node;
1473 
1474 	mutex_lock(&vm->mutex);
1475 	node = __drm_mm_interval_first(&vm->mm,
1476 				       offset, offset + sizeof(u32) - 1);
1477 	mutex_unlock(&vm->mutex);
1478 	if (!node || node->start > offset)
1479 		return 0;
1480 
1481 	GEM_BUG_ON(offset >= node->start + node->size);
1482 
1483 	pr_err("Target offset 0x%08x_%08x overlaps with a node in the mm!\n",
1484 	       upper_32_bits(offset), lower_32_bits(offset));
1485 	return -EINVAL;
1486 }
1487 
1488 static int write_to_scratch(struct i915_gem_context *ctx,
1489 			    struct intel_engine_cs *engine,
1490 			    u64 offset, u32 value)
1491 {
1492 	struct drm_i915_private *i915 = ctx->i915;
1493 	struct drm_i915_gem_object *obj;
1494 	struct i915_address_space *vm;
1495 	struct i915_request *rq;
1496 	struct i915_vma *vma;
1497 	u32 *cmd;
1498 	int err;
1499 
1500 	GEM_BUG_ON(offset < I915_GTT_PAGE_SIZE);
1501 
1502 	err = check_scratch(ctx_vm(ctx), offset);
1503 	if (err)
1504 		return err;
1505 
1506 	obj = i915_gem_object_create_internal(i915, PAGE_SIZE);
1507 	if (IS_ERR(obj))
1508 		return PTR_ERR(obj);
1509 
1510 	cmd = i915_gem_object_pin_map_unlocked(obj, I915_MAP_WB);
1511 	if (IS_ERR(cmd)) {
1512 		err = PTR_ERR(cmd);
1513 		goto out;
1514 	}
1515 
1516 	*cmd++ = MI_STORE_DWORD_IMM_GEN4;
1517 	if (GRAPHICS_VER(i915) >= 8) {
1518 		*cmd++ = lower_32_bits(offset);
1519 		*cmd++ = upper_32_bits(offset);
1520 	} else {
1521 		*cmd++ = 0;
1522 		*cmd++ = offset;
1523 	}
1524 	*cmd++ = value;
1525 	*cmd = MI_BATCH_BUFFER_END;
1526 	__i915_gem_object_flush_map(obj, 0, 64);
1527 	i915_gem_object_unpin_map(obj);
1528 
1529 	intel_gt_chipset_flush(engine->gt);
1530 
1531 	vm = i915_gem_context_get_vm_rcu(ctx);
1532 	vma = i915_vma_instance(obj, vm, NULL);
1533 	if (IS_ERR(vma)) {
1534 		err = PTR_ERR(vma);
1535 		goto out_vm;
1536 	}
1537 
1538 	err = i915_vma_pin(vma, 0, 0, PIN_USER | PIN_OFFSET_FIXED);
1539 	if (err)
1540 		goto out_vm;
1541 
1542 	rq = igt_request_alloc(ctx, engine);
1543 	if (IS_ERR(rq)) {
1544 		err = PTR_ERR(rq);
1545 		goto err_unpin;
1546 	}
1547 
1548 	i915_vma_lock(vma);
1549 	err = i915_request_await_object(rq, vma->obj, false);
1550 	if (err == 0)
1551 		err = i915_vma_move_to_active(vma, rq, 0);
1552 	i915_vma_unlock(vma);
1553 	if (err)
1554 		goto skip_request;
1555 
1556 	if (rq->engine->emit_init_breadcrumb) {
1557 		err = rq->engine->emit_init_breadcrumb(rq);
1558 		if (err)
1559 			goto skip_request;
1560 	}
1561 
1562 	err = engine->emit_bb_start(rq, vma->node.start, vma->node.size, 0);
1563 	if (err)
1564 		goto skip_request;
1565 
1566 	i915_vma_unpin(vma);
1567 
1568 	i915_request_add(rq);
1569 
1570 	goto out_vm;
1571 skip_request:
1572 	i915_request_set_error_once(rq, err);
1573 	i915_request_add(rq);
1574 err_unpin:
1575 	i915_vma_unpin(vma);
1576 out_vm:
1577 	i915_vm_put(vm);
1578 out:
1579 	i915_gem_object_put(obj);
1580 	return err;
1581 }
1582 
1583 static int read_from_scratch(struct i915_gem_context *ctx,
1584 			     struct intel_engine_cs *engine,
1585 			     u64 offset, u32 *value)
1586 {
1587 	struct drm_i915_private *i915 = ctx->i915;
1588 	struct drm_i915_gem_object *obj;
1589 	struct i915_address_space *vm;
1590 	const u32 result = 0x100;
1591 	struct i915_request *rq;
1592 	struct i915_vma *vma;
1593 	unsigned int flags;
1594 	u32 *cmd;
1595 	int err;
1596 
1597 	GEM_BUG_ON(offset < I915_GTT_PAGE_SIZE);
1598 
1599 	err = check_scratch(ctx_vm(ctx), offset);
1600 	if (err)
1601 		return err;
1602 
1603 	obj = i915_gem_object_create_internal(i915, PAGE_SIZE);
1604 	if (IS_ERR(obj))
1605 		return PTR_ERR(obj);
1606 
1607 	if (GRAPHICS_VER(i915) >= 8) {
1608 		const u32 GPR0 = engine->mmio_base + 0x600;
1609 
1610 		vm = i915_gem_context_get_vm_rcu(ctx);
1611 		vma = i915_vma_instance(obj, vm, NULL);
1612 		if (IS_ERR(vma)) {
1613 			err = PTR_ERR(vma);
1614 			goto out_vm;
1615 		}
1616 
1617 		err = i915_vma_pin(vma, 0, 0, PIN_USER | PIN_OFFSET_FIXED);
1618 		if (err)
1619 			goto out_vm;
1620 
1621 		cmd = i915_gem_object_pin_map_unlocked(obj, I915_MAP_WB);
1622 		if (IS_ERR(cmd)) {
1623 			err = PTR_ERR(cmd);
1624 			goto out;
1625 		}
1626 
1627 		memset(cmd, POISON_INUSE, PAGE_SIZE);
1628 		*cmd++ = MI_LOAD_REGISTER_MEM_GEN8;
1629 		*cmd++ = GPR0;
1630 		*cmd++ = lower_32_bits(offset);
1631 		*cmd++ = upper_32_bits(offset);
1632 		*cmd++ = MI_STORE_REGISTER_MEM_GEN8;
1633 		*cmd++ = GPR0;
1634 		*cmd++ = result;
1635 		*cmd++ = 0;
1636 		*cmd = MI_BATCH_BUFFER_END;
1637 
1638 		i915_gem_object_flush_map(obj);
1639 		i915_gem_object_unpin_map(obj);
1640 
1641 		flags = 0;
1642 	} else {
1643 		const u32 reg = engine->mmio_base + 0x420;
1644 
1645 		/* hsw: register access even to 3DPRIM! is protected */
1646 		vm = i915_vm_get(&engine->gt->ggtt->vm);
1647 		vma = i915_vma_instance(obj, vm, NULL);
1648 		if (IS_ERR(vma)) {
1649 			err = PTR_ERR(vma);
1650 			goto out_vm;
1651 		}
1652 
1653 		err = i915_vma_pin(vma, 0, 0, PIN_GLOBAL);
1654 		if (err)
1655 			goto out_vm;
1656 
1657 		cmd = i915_gem_object_pin_map_unlocked(obj, I915_MAP_WB);
1658 		if (IS_ERR(cmd)) {
1659 			err = PTR_ERR(cmd);
1660 			goto out;
1661 		}
1662 
1663 		memset(cmd, POISON_INUSE, PAGE_SIZE);
1664 		*cmd++ = MI_LOAD_REGISTER_MEM;
1665 		*cmd++ = reg;
1666 		*cmd++ = offset;
1667 		*cmd++ = MI_STORE_REGISTER_MEM | MI_USE_GGTT;
1668 		*cmd++ = reg;
1669 		*cmd++ = vma->node.start + result;
1670 		*cmd = MI_BATCH_BUFFER_END;
1671 
1672 		i915_gem_object_flush_map(obj);
1673 		i915_gem_object_unpin_map(obj);
1674 
1675 		flags = I915_DISPATCH_SECURE;
1676 	}
1677 
1678 	intel_gt_chipset_flush(engine->gt);
1679 
1680 	rq = igt_request_alloc(ctx, engine);
1681 	if (IS_ERR(rq)) {
1682 		err = PTR_ERR(rq);
1683 		goto err_unpin;
1684 	}
1685 
1686 	i915_vma_lock(vma);
1687 	err = i915_request_await_object(rq, vma->obj, true);
1688 	if (err == 0)
1689 		err = i915_vma_move_to_active(vma, rq, EXEC_OBJECT_WRITE);
1690 	i915_vma_unlock(vma);
1691 	if (err)
1692 		goto skip_request;
1693 
1694 	if (rq->engine->emit_init_breadcrumb) {
1695 		err = rq->engine->emit_init_breadcrumb(rq);
1696 		if (err)
1697 			goto skip_request;
1698 	}
1699 
1700 	err = engine->emit_bb_start(rq, vma->node.start, vma->node.size, flags);
1701 	if (err)
1702 		goto skip_request;
1703 
1704 	i915_vma_unpin(vma);
1705 
1706 	i915_request_add(rq);
1707 
1708 	i915_gem_object_lock(obj, NULL);
1709 	err = i915_gem_object_set_to_cpu_domain(obj, false);
1710 	i915_gem_object_unlock(obj);
1711 	if (err)
1712 		goto out_vm;
1713 
1714 	cmd = i915_gem_object_pin_map_unlocked(obj, I915_MAP_WB);
1715 	if (IS_ERR(cmd)) {
1716 		err = PTR_ERR(cmd);
1717 		goto out_vm;
1718 	}
1719 
1720 	*value = cmd[result / sizeof(*cmd)];
1721 	i915_gem_object_unpin_map(obj);
1722 
1723 	goto out_vm;
1724 skip_request:
1725 	i915_request_set_error_once(rq, err);
1726 	i915_request_add(rq);
1727 err_unpin:
1728 	i915_vma_unpin(vma);
1729 out_vm:
1730 	i915_vm_put(vm);
1731 out:
1732 	i915_gem_object_put(obj);
1733 	return err;
1734 }
1735 
1736 static int check_scratch_page(struct i915_gem_context *ctx, u32 *out)
1737 {
1738 	struct i915_address_space *vm;
1739 	u32 *vaddr;
1740 	int err = 0;
1741 
1742 	vm = ctx_vm(ctx);
1743 	if (!vm)
1744 		return -ENODEV;
1745 
1746 	if (!vm->scratch[0]) {
1747 		pr_err("No scratch page!\n");
1748 		return -EINVAL;
1749 	}
1750 
1751 	vaddr = __px_vaddr(vm->scratch[0]);
1752 
1753 	memcpy(out, vaddr, sizeof(*out));
1754 	if (memchr_inv(vaddr, *out, PAGE_SIZE)) {
1755 		pr_err("Inconsistent initial state of scratch page!\n");
1756 		err = -EINVAL;
1757 	}
1758 
1759 	return err;
1760 }
1761 
1762 static int igt_vm_isolation(void *arg)
1763 {
1764 	struct drm_i915_private *i915 = arg;
1765 	struct i915_gem_context *ctx_a, *ctx_b;
1766 	unsigned long num_engines, count;
1767 	struct intel_engine_cs *engine;
1768 	struct igt_live_test t;
1769 	I915_RND_STATE(prng);
1770 	struct file *file;
1771 	u64 vm_total;
1772 	u32 expected;
1773 	int err;
1774 
1775 	if (GRAPHICS_VER(i915) < 7)
1776 		return 0;
1777 
1778 	/*
1779 	 * The simple goal here is that a write into one context is not
1780 	 * observed in a second (separate page tables and scratch).
1781 	 */
1782 
1783 	file = mock_file(i915);
1784 	if (IS_ERR(file))
1785 		return PTR_ERR(file);
1786 
1787 	err = igt_live_test_begin(&t, i915, __func__, "");
1788 	if (err)
1789 		goto out_file;
1790 
1791 	ctx_a = live_context(i915, file);
1792 	if (IS_ERR(ctx_a)) {
1793 		err = PTR_ERR(ctx_a);
1794 		goto out_file;
1795 	}
1796 
1797 	ctx_b = live_context(i915, file);
1798 	if (IS_ERR(ctx_b)) {
1799 		err = PTR_ERR(ctx_b);
1800 		goto out_file;
1801 	}
1802 
1803 	/* We can only test vm isolation, if the vm are distinct */
1804 	if (ctx_vm(ctx_a) == ctx_vm(ctx_b))
1805 		goto out_file;
1806 
1807 	/* Read the initial state of the scratch page */
1808 	err = check_scratch_page(ctx_a, &expected);
1809 	if (err)
1810 		goto out_file;
1811 
1812 	err = check_scratch_page(ctx_b, &expected);
1813 	if (err)
1814 		goto out_file;
1815 
1816 	vm_total = ctx_vm(ctx_a)->total;
1817 	GEM_BUG_ON(ctx_vm(ctx_b)->total != vm_total);
1818 
1819 	count = 0;
1820 	num_engines = 0;
1821 	for_each_uabi_engine(engine, i915) {
1822 		IGT_TIMEOUT(end_time);
1823 		unsigned long this = 0;
1824 
1825 		if (!intel_engine_can_store_dword(engine))
1826 			continue;
1827 
1828 		/* Not all engines have their own GPR! */
1829 		if (GRAPHICS_VER(i915) < 8 && engine->class != RENDER_CLASS)
1830 			continue;
1831 
1832 		while (!__igt_timeout(end_time, NULL)) {
1833 			u32 value = 0xc5c5c5c5;
1834 			u64 offset;
1835 
1836 			/* Leave enough space at offset 0 for the batch */
1837 			offset = igt_random_offset(&prng,
1838 						   I915_GTT_PAGE_SIZE, vm_total,
1839 						   sizeof(u32), alignof_dword);
1840 
1841 			err = write_to_scratch(ctx_a, engine,
1842 					       offset, 0xdeadbeef);
1843 			if (err == 0)
1844 				err = read_from_scratch(ctx_b, engine,
1845 							offset, &value);
1846 			if (err)
1847 				goto out_file;
1848 
1849 			if (value != expected) {
1850 				pr_err("%s: Read %08x from scratch (offset 0x%08x_%08x), after %lu reads!\n",
1851 				       engine->name, value,
1852 				       upper_32_bits(offset),
1853 				       lower_32_bits(offset),
1854 				       this);
1855 				err = -EINVAL;
1856 				goto out_file;
1857 			}
1858 
1859 			this++;
1860 		}
1861 		count += this;
1862 		num_engines++;
1863 	}
1864 	pr_info("Checked %lu scratch offsets across %lu engines\n",
1865 		count, num_engines);
1866 
1867 out_file:
1868 	if (igt_live_test_end(&t))
1869 		err = -EIO;
1870 	fput(file);
1871 	return err;
1872 }
1873 
1874 int i915_gem_context_live_selftests(struct drm_i915_private *i915)
1875 {
1876 	static const struct i915_subtest tests[] = {
1877 		SUBTEST(live_nop_switch),
1878 		SUBTEST(live_parallel_switch),
1879 		SUBTEST(igt_ctx_exec),
1880 		SUBTEST(igt_ctx_readonly),
1881 		SUBTEST(igt_ctx_sseu),
1882 		SUBTEST(igt_shared_ctx_exec),
1883 		SUBTEST(igt_vm_isolation),
1884 	};
1885 
1886 	if (intel_gt_is_wedged(&i915->gt))
1887 		return 0;
1888 
1889 	return i915_live_subtests(tests, i915);
1890 }
1891