1 /*
2  * SPDX-License-Identifier: MIT
3  *
4  * Copyright © 2008,2010 Intel Corporation
5  */
6 
7 #include <linux/intel-iommu.h>
8 #include <linux/dma-resv.h>
9 #include <linux/sync_file.h>
10 #include <linux/uaccess.h>
11 
12 #include <drm/drm_syncobj.h>
13 
14 #include "display/intel_frontbuffer.h"
15 
16 #include "gem/i915_gem_ioctls.h"
17 #include "gt/intel_context.h"
18 #include "gt/intel_gt.h"
19 #include "gt/intel_gt_buffer_pool.h"
20 #include "gt/intel_gt_pm.h"
21 #include "gt/intel_ring.h"
22 
23 #include "i915_drv.h"
24 #include "i915_gem_clflush.h"
25 #include "i915_gem_context.h"
26 #include "i915_gem_ioctls.h"
27 #include "i915_sw_fence_work.h"
28 #include "i915_trace.h"
29 
30 struct eb_vma {
31 	struct i915_vma *vma;
32 	unsigned int flags;
33 
34 	/** This vma's place in the execbuf reservation list */
35 	struct drm_i915_gem_exec_object2 *exec;
36 	struct list_head bind_link;
37 	struct list_head reloc_link;
38 
39 	struct hlist_node node;
40 	u32 handle;
41 };
42 
43 struct eb_vma_array {
44 	struct kref kref;
45 	struct eb_vma vma[];
46 };
47 
48 enum {
49 	FORCE_CPU_RELOC = 1,
50 	FORCE_GTT_RELOC,
51 	FORCE_GPU_RELOC,
52 #define DBG_FORCE_RELOC 0 /* choose one of the above! */
53 };
54 
55 #define __EXEC_OBJECT_HAS_PIN		BIT(31)
56 #define __EXEC_OBJECT_HAS_FENCE		BIT(30)
57 #define __EXEC_OBJECT_NEEDS_MAP		BIT(29)
58 #define __EXEC_OBJECT_NEEDS_BIAS	BIT(28)
59 #define __EXEC_OBJECT_INTERNAL_FLAGS	(~0u << 28) /* all of the above */
60 
61 #define __EXEC_HAS_RELOC	BIT(31)
62 #define __EXEC_INTERNAL_FLAGS	(~0u << 31)
63 #define UPDATE			PIN_OFFSET_FIXED
64 
65 #define BATCH_OFFSET_BIAS (256*1024)
66 
67 #define __I915_EXEC_ILLEGAL_FLAGS \
68 	(__I915_EXEC_UNKNOWN_FLAGS | \
69 	 I915_EXEC_CONSTANTS_MASK  | \
70 	 I915_EXEC_RESOURCE_STREAMER)
71 
72 /* Catch emission of unexpected errors for CI! */
73 #if IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM)
74 #undef EINVAL
75 #define EINVAL ({ \
76 	DRM_DEBUG_DRIVER("EINVAL at %s:%d\n", __func__, __LINE__); \
77 	22; \
78 })
79 #endif
80 
81 /**
82  * DOC: User command execution
83  *
84  * Userspace submits commands to be executed on the GPU as an instruction
85  * stream within a GEM object we call a batchbuffer. This instructions may
86  * refer to other GEM objects containing auxiliary state such as kernels,
87  * samplers, render targets and even secondary batchbuffers. Userspace does
88  * not know where in the GPU memory these objects reside and so before the
89  * batchbuffer is passed to the GPU for execution, those addresses in the
90  * batchbuffer and auxiliary objects are updated. This is known as relocation,
91  * or patching. To try and avoid having to relocate each object on the next
92  * execution, userspace is told the location of those objects in this pass,
93  * but this remains just a hint as the kernel may choose a new location for
94  * any object in the future.
95  *
96  * At the level of talking to the hardware, submitting a batchbuffer for the
97  * GPU to execute is to add content to a buffer from which the HW
98  * command streamer is reading.
99  *
100  * 1. Add a command to load the HW context. For Logical Ring Contexts, i.e.
101  *    Execlists, this command is not placed on the same buffer as the
102  *    remaining items.
103  *
104  * 2. Add a command to invalidate caches to the buffer.
105  *
106  * 3. Add a batchbuffer start command to the buffer; the start command is
107  *    essentially a token together with the GPU address of the batchbuffer
108  *    to be executed.
109  *
110  * 4. Add a pipeline flush to the buffer.
111  *
112  * 5. Add a memory write command to the buffer to record when the GPU
113  *    is done executing the batchbuffer. The memory write writes the
114  *    global sequence number of the request, ``i915_request::global_seqno``;
115  *    the i915 driver uses the current value in the register to determine
116  *    if the GPU has completed the batchbuffer.
117  *
118  * 6. Add a user interrupt command to the buffer. This command instructs
119  *    the GPU to issue an interrupt when the command, pipeline flush and
120  *    memory write are completed.
121  *
122  * 7. Inform the hardware of the additional commands added to the buffer
123  *    (by updating the tail pointer).
124  *
125  * Processing an execbuf ioctl is conceptually split up into a few phases.
126  *
127  * 1. Validation - Ensure all the pointers, handles and flags are valid.
128  * 2. Reservation - Assign GPU address space for every object
129  * 3. Relocation - Update any addresses to point to the final locations
130  * 4. Serialisation - Order the request with respect to its dependencies
131  * 5. Construction - Construct a request to execute the batchbuffer
132  * 6. Submission (at some point in the future execution)
133  *
134  * Reserving resources for the execbuf is the most complicated phase. We
135  * neither want to have to migrate the object in the address space, nor do
136  * we want to have to update any relocations pointing to this object. Ideally,
137  * we want to leave the object where it is and for all the existing relocations
138  * to match. If the object is given a new address, or if userspace thinks the
139  * object is elsewhere, we have to parse all the relocation entries and update
140  * the addresses. Userspace can set the I915_EXEC_NORELOC flag to hint that
141  * all the target addresses in all of its objects match the value in the
142  * relocation entries and that they all match the presumed offsets given by the
143  * list of execbuffer objects. Using this knowledge, we know that if we haven't
144  * moved any buffers, all the relocation entries are valid and we can skip
145  * the update. (If userspace is wrong, the likely outcome is an impromptu GPU
146  * hang.) The requirement for using I915_EXEC_NO_RELOC are:
147  *
148  *      The addresses written in the objects must match the corresponding
149  *      reloc.presumed_offset which in turn must match the corresponding
150  *      execobject.offset.
151  *
152  *      Any render targets written to in the batch must be flagged with
153  *      EXEC_OBJECT_WRITE.
154  *
155  *      To avoid stalling, execobject.offset should match the current
156  *      address of that object within the active context.
157  *
158  * The reservation is done is multiple phases. First we try and keep any
159  * object already bound in its current location - so as long as meets the
160  * constraints imposed by the new execbuffer. Any object left unbound after the
161  * first pass is then fitted into any available idle space. If an object does
162  * not fit, all objects are removed from the reservation and the process rerun
163  * after sorting the objects into a priority order (more difficult to fit
164  * objects are tried first). Failing that, the entire VM is cleared and we try
165  * to fit the execbuf once last time before concluding that it simply will not
166  * fit.
167  *
168  * A small complication to all of this is that we allow userspace not only to
169  * specify an alignment and a size for the object in the address space, but
170  * we also allow userspace to specify the exact offset. This objects are
171  * simpler to place (the location is known a priori) all we have to do is make
172  * sure the space is available.
173  *
174  * Once all the objects are in place, patching up the buried pointers to point
175  * to the final locations is a fairly simple job of walking over the relocation
176  * entry arrays, looking up the right address and rewriting the value into
177  * the object. Simple! ... The relocation entries are stored in user memory
178  * and so to access them we have to copy them into a local buffer. That copy
179  * has to avoid taking any pagefaults as they may lead back to a GEM object
180  * requiring the struct_mutex (i.e. recursive deadlock). So once again we split
181  * the relocation into multiple passes. First we try to do everything within an
182  * atomic context (avoid the pagefaults) which requires that we never wait. If
183  * we detect that we may wait, or if we need to fault, then we have to fallback
184  * to a slower path. The slowpath has to drop the mutex. (Can you hear alarm
185  * bells yet?) Dropping the mutex means that we lose all the state we have
186  * built up so far for the execbuf and we must reset any global data. However,
187  * we do leave the objects pinned in their final locations - which is a
188  * potential issue for concurrent execbufs. Once we have left the mutex, we can
189  * allocate and copy all the relocation entries into a large array at our
190  * leisure, reacquire the mutex, reclaim all the objects and other state and
191  * then proceed to update any incorrect addresses with the objects.
192  *
193  * As we process the relocation entries, we maintain a record of whether the
194  * object is being written to. Using NORELOC, we expect userspace to provide
195  * this information instead. We also check whether we can skip the relocation
196  * by comparing the expected value inside the relocation entry with the target's
197  * final address. If they differ, we have to map the current object and rewrite
198  * the 4 or 8 byte pointer within.
199  *
200  * Serialising an execbuf is quite simple according to the rules of the GEM
201  * ABI. Execution within each context is ordered by the order of submission.
202  * Writes to any GEM object are in order of submission and are exclusive. Reads
203  * from a GEM object are unordered with respect to other reads, but ordered by
204  * writes. A write submitted after a read cannot occur before the read, and
205  * similarly any read submitted after a write cannot occur before the write.
206  * Writes are ordered between engines such that only one write occurs at any
207  * time (completing any reads beforehand) - using semaphores where available
208  * and CPU serialisation otherwise. Other GEM access obey the same rules, any
209  * write (either via mmaps using set-domain, or via pwrite) must flush all GPU
210  * reads before starting, and any read (either using set-domain or pread) must
211  * flush all GPU writes before starting. (Note we only employ a barrier before,
212  * we currently rely on userspace not concurrently starting a new execution
213  * whilst reading or writing to an object. This may be an advantage or not
214  * depending on how much you trust userspace not to shoot themselves in the
215  * foot.) Serialisation may just result in the request being inserted into
216  * a DAG awaiting its turn, but most simple is to wait on the CPU until
217  * all dependencies are resolved.
218  *
219  * After all of that, is just a matter of closing the request and handing it to
220  * the hardware (well, leaving it in a queue to be executed). However, we also
221  * offer the ability for batchbuffers to be run with elevated privileges so
222  * that they access otherwise hidden registers. (Used to adjust L3 cache etc.)
223  * Before any batch is given extra privileges we first must check that it
224  * contains no nefarious instructions, we check that each instruction is from
225  * our whitelist and all registers are also from an allowed list. We first
226  * copy the user's batchbuffer to a shadow (so that the user doesn't have
227  * access to it, either by the CPU or GPU as we scan it) and then parse each
228  * instruction. If everything is ok, we set a flag telling the hardware to run
229  * the batchbuffer in trusted mode, otherwise the ioctl is rejected.
230  */
231 
232 struct i915_execbuffer {
233 	struct drm_i915_private *i915; /** i915 backpointer */
234 	struct drm_file *file; /** per-file lookup tables and limits */
235 	struct drm_i915_gem_execbuffer2 *args; /** ioctl parameters */
236 	struct drm_i915_gem_exec_object2 *exec; /** ioctl execobj[] */
237 	struct eb_vma *vma;
238 
239 	struct intel_engine_cs *engine; /** engine to queue the request to */
240 	struct intel_context *context; /* logical state for the request */
241 	struct i915_gem_context *gem_context; /** caller's context */
242 
243 	struct i915_request *request; /** our request to build */
244 	struct eb_vma *batch; /** identity of the batch obj/vma */
245 	struct i915_vma *trampoline; /** trampoline used for chaining */
246 
247 	/** actual size of execobj[] as we may extend it for the cmdparser */
248 	unsigned int buffer_count;
249 
250 	/** list of vma not yet bound during reservation phase */
251 	struct list_head unbound;
252 
253 	/** list of vma that have execobj.relocation_count */
254 	struct list_head relocs;
255 
256 	/**
257 	 * Track the most recently used object for relocations, as we
258 	 * frequently have to perform multiple relocations within the same
259 	 * obj/page
260 	 */
261 	struct reloc_cache {
262 		struct drm_mm_node node; /** temporary GTT binding */
263 		unsigned long vaddr; /** Current kmap address */
264 		unsigned long page; /** Currently mapped page index */
265 		unsigned int gen; /** Cached value of INTEL_GEN */
266 		bool use_64bit_reloc : 1;
267 		bool has_llc : 1;
268 		bool has_fence : 1;
269 		bool needs_unfenced : 1;
270 
271 		struct i915_vma *target;
272 		struct i915_request *rq;
273 		struct i915_vma *rq_vma;
274 		u32 *rq_cmd;
275 		unsigned int rq_size;
276 	} reloc_cache;
277 
278 	u64 invalid_flags; /** Set of execobj.flags that are invalid */
279 	u32 context_flags; /** Set of execobj.flags to insert from the ctx */
280 
281 	u32 batch_start_offset; /** Location within object of batch */
282 	u32 batch_len; /** Length of batch within object */
283 	u32 batch_flags; /** Flags composed for emit_bb_start() */
284 
285 	/**
286 	 * Indicate either the size of the hastable used to resolve
287 	 * relocation handles, or if negative that we are using a direct
288 	 * index into the execobj[].
289 	 */
290 	int lut_size;
291 	struct hlist_head *buckets; /** ht for relocation handles */
292 	struct eb_vma_array *array;
293 };
294 
295 static inline bool eb_use_cmdparser(const struct i915_execbuffer *eb)
296 {
297 	return intel_engine_requires_cmd_parser(eb->engine) ||
298 		(intel_engine_using_cmd_parser(eb->engine) &&
299 		 eb->args->batch_len);
300 }
301 
302 static struct eb_vma_array *eb_vma_array_create(unsigned int count)
303 {
304 	struct eb_vma_array *arr;
305 
306 	arr = kvmalloc(struct_size(arr, vma, count), GFP_KERNEL | __GFP_NOWARN);
307 	if (!arr)
308 		return NULL;
309 
310 	kref_init(&arr->kref);
311 	arr->vma[0].vma = NULL;
312 
313 	return arr;
314 }
315 
316 static inline void eb_unreserve_vma(struct eb_vma *ev)
317 {
318 	struct i915_vma *vma = ev->vma;
319 
320 	if (unlikely(ev->flags & __EXEC_OBJECT_HAS_FENCE))
321 		__i915_vma_unpin_fence(vma);
322 
323 	if (ev->flags & __EXEC_OBJECT_HAS_PIN)
324 		__i915_vma_unpin(vma);
325 
326 	ev->flags &= ~(__EXEC_OBJECT_HAS_PIN |
327 		       __EXEC_OBJECT_HAS_FENCE);
328 }
329 
330 static void eb_vma_array_destroy(struct kref *kref)
331 {
332 	struct eb_vma_array *arr = container_of(kref, typeof(*arr), kref);
333 	struct eb_vma *ev = arr->vma;
334 
335 	while (ev->vma) {
336 		eb_unreserve_vma(ev);
337 		i915_vma_put(ev->vma);
338 		ev++;
339 	}
340 
341 	kvfree(arr);
342 }
343 
344 static void eb_vma_array_put(struct eb_vma_array *arr)
345 {
346 	kref_put(&arr->kref, eb_vma_array_destroy);
347 }
348 
349 static int eb_create(struct i915_execbuffer *eb)
350 {
351 	/* Allocate an extra slot for use by the command parser + sentinel */
352 	eb->array = eb_vma_array_create(eb->buffer_count + 2);
353 	if (!eb->array)
354 		return -ENOMEM;
355 
356 	eb->vma = eb->array->vma;
357 
358 	if (!(eb->args->flags & I915_EXEC_HANDLE_LUT)) {
359 		unsigned int size = 1 + ilog2(eb->buffer_count);
360 
361 		/*
362 		 * Without a 1:1 association between relocation handles and
363 		 * the execobject[] index, we instead create a hashtable.
364 		 * We size it dynamically based on available memory, starting
365 		 * first with 1:1 assocative hash and scaling back until
366 		 * the allocation succeeds.
367 		 *
368 		 * Later on we use a positive lut_size to indicate we are
369 		 * using this hashtable, and a negative value to indicate a
370 		 * direct lookup.
371 		 */
372 		do {
373 			gfp_t flags;
374 
375 			/* While we can still reduce the allocation size, don't
376 			 * raise a warning and allow the allocation to fail.
377 			 * On the last pass though, we want to try as hard
378 			 * as possible to perform the allocation and warn
379 			 * if it fails.
380 			 */
381 			flags = GFP_KERNEL;
382 			if (size > 1)
383 				flags |= __GFP_NORETRY | __GFP_NOWARN;
384 
385 			eb->buckets = kzalloc(sizeof(struct hlist_head) << size,
386 					      flags);
387 			if (eb->buckets)
388 				break;
389 		} while (--size);
390 
391 		if (unlikely(!size)) {
392 			eb_vma_array_put(eb->array);
393 			return -ENOMEM;
394 		}
395 
396 		eb->lut_size = size;
397 	} else {
398 		eb->lut_size = -eb->buffer_count;
399 	}
400 
401 	return 0;
402 }
403 
404 static bool
405 eb_vma_misplaced(const struct drm_i915_gem_exec_object2 *entry,
406 		 const struct i915_vma *vma,
407 		 unsigned int flags)
408 {
409 	if (vma->node.size < entry->pad_to_size)
410 		return true;
411 
412 	if (entry->alignment && !IS_ALIGNED(vma->node.start, entry->alignment))
413 		return true;
414 
415 	if (flags & EXEC_OBJECT_PINNED &&
416 	    vma->node.start != entry->offset)
417 		return true;
418 
419 	if (flags & __EXEC_OBJECT_NEEDS_BIAS &&
420 	    vma->node.start < BATCH_OFFSET_BIAS)
421 		return true;
422 
423 	if (!(flags & EXEC_OBJECT_SUPPORTS_48B_ADDRESS) &&
424 	    (vma->node.start + vma->node.size - 1) >> 32)
425 		return true;
426 
427 	if (flags & __EXEC_OBJECT_NEEDS_MAP &&
428 	    !i915_vma_is_map_and_fenceable(vma))
429 		return true;
430 
431 	return false;
432 }
433 
434 static u64 eb_pin_flags(const struct drm_i915_gem_exec_object2 *entry,
435 			unsigned int exec_flags)
436 {
437 	u64 pin_flags = 0;
438 
439 	if (exec_flags & EXEC_OBJECT_NEEDS_GTT)
440 		pin_flags |= PIN_GLOBAL;
441 
442 	/*
443 	 * Wa32bitGeneralStateOffset & Wa32bitInstructionBaseOffset,
444 	 * limit address to the first 4GBs for unflagged objects.
445 	 */
446 	if (!(exec_flags & EXEC_OBJECT_SUPPORTS_48B_ADDRESS))
447 		pin_flags |= PIN_ZONE_4G;
448 
449 	if (exec_flags & __EXEC_OBJECT_NEEDS_MAP)
450 		pin_flags |= PIN_MAPPABLE;
451 
452 	if (exec_flags & EXEC_OBJECT_PINNED)
453 		pin_flags |= entry->offset | PIN_OFFSET_FIXED;
454 	else if (exec_flags & __EXEC_OBJECT_NEEDS_BIAS)
455 		pin_flags |= BATCH_OFFSET_BIAS | PIN_OFFSET_BIAS;
456 
457 	return pin_flags;
458 }
459 
460 static inline bool
461 eb_pin_vma(struct i915_execbuffer *eb,
462 	   const struct drm_i915_gem_exec_object2 *entry,
463 	   struct eb_vma *ev)
464 {
465 	struct i915_vma *vma = ev->vma;
466 	u64 pin_flags;
467 
468 	if (vma->node.size)
469 		pin_flags = vma->node.start;
470 	else
471 		pin_flags = entry->offset & PIN_OFFSET_MASK;
472 
473 	pin_flags |= PIN_USER | PIN_NOEVICT | PIN_OFFSET_FIXED;
474 	if (unlikely(ev->flags & EXEC_OBJECT_NEEDS_GTT))
475 		pin_flags |= PIN_GLOBAL;
476 
477 	/* Attempt to reuse the current location if available */
478 	if (unlikely(i915_vma_pin(vma, 0, 0, pin_flags))) {
479 		if (entry->flags & EXEC_OBJECT_PINNED)
480 			return false;
481 
482 		/* Failing that pick any _free_ space if suitable */
483 		if (unlikely(i915_vma_pin(vma,
484 					  entry->pad_to_size,
485 					  entry->alignment,
486 					  eb_pin_flags(entry, ev->flags) |
487 					  PIN_USER | PIN_NOEVICT)))
488 			return false;
489 	}
490 
491 	if (unlikely(ev->flags & EXEC_OBJECT_NEEDS_FENCE)) {
492 		if (unlikely(i915_vma_pin_fence(vma))) {
493 			i915_vma_unpin(vma);
494 			return false;
495 		}
496 
497 		if (vma->fence)
498 			ev->flags |= __EXEC_OBJECT_HAS_FENCE;
499 	}
500 
501 	ev->flags |= __EXEC_OBJECT_HAS_PIN;
502 	return !eb_vma_misplaced(entry, vma, ev->flags);
503 }
504 
505 static int
506 eb_validate_vma(struct i915_execbuffer *eb,
507 		struct drm_i915_gem_exec_object2 *entry,
508 		struct i915_vma *vma)
509 {
510 	if (unlikely(entry->flags & eb->invalid_flags))
511 		return -EINVAL;
512 
513 	if (unlikely(entry->alignment &&
514 		     !is_power_of_2_u64(entry->alignment)))
515 		return -EINVAL;
516 
517 	/*
518 	 * Offset can be used as input (EXEC_OBJECT_PINNED), reject
519 	 * any non-page-aligned or non-canonical addresses.
520 	 */
521 	if (unlikely(entry->flags & EXEC_OBJECT_PINNED &&
522 		     entry->offset != gen8_canonical_addr(entry->offset & I915_GTT_PAGE_MASK)))
523 		return -EINVAL;
524 
525 	/* pad_to_size was once a reserved field, so sanitize it */
526 	if (entry->flags & EXEC_OBJECT_PAD_TO_SIZE) {
527 		if (unlikely(offset_in_page(entry->pad_to_size)))
528 			return -EINVAL;
529 	} else {
530 		entry->pad_to_size = 0;
531 	}
532 	/*
533 	 * From drm_mm perspective address space is continuous,
534 	 * so from this point we're always using non-canonical
535 	 * form internally.
536 	 */
537 	entry->offset = gen8_noncanonical_addr(entry->offset);
538 
539 	if (!eb->reloc_cache.has_fence) {
540 		entry->flags &= ~EXEC_OBJECT_NEEDS_FENCE;
541 	} else {
542 		if ((entry->flags & EXEC_OBJECT_NEEDS_FENCE ||
543 		     eb->reloc_cache.needs_unfenced) &&
544 		    i915_gem_object_is_tiled(vma->obj))
545 			entry->flags |= EXEC_OBJECT_NEEDS_GTT | __EXEC_OBJECT_NEEDS_MAP;
546 	}
547 
548 	if (!(entry->flags & EXEC_OBJECT_PINNED))
549 		entry->flags |= eb->context_flags;
550 
551 	return 0;
552 }
553 
554 static void
555 eb_add_vma(struct i915_execbuffer *eb,
556 	   unsigned int i, unsigned batch_idx,
557 	   struct i915_vma *vma)
558 {
559 	struct drm_i915_gem_exec_object2 *entry = &eb->exec[i];
560 	struct eb_vma *ev = &eb->vma[i];
561 
562 	GEM_BUG_ON(i915_vma_is_closed(vma));
563 
564 	ev->vma = vma;
565 	ev->exec = entry;
566 	ev->flags = entry->flags;
567 
568 	if (eb->lut_size > 0) {
569 		ev->handle = entry->handle;
570 		hlist_add_head(&ev->node,
571 			       &eb->buckets[hash_32(entry->handle,
572 						    eb->lut_size)]);
573 	}
574 
575 	if (entry->relocation_count)
576 		list_add_tail(&ev->reloc_link, &eb->relocs);
577 
578 	/*
579 	 * SNA is doing fancy tricks with compressing batch buffers, which leads
580 	 * to negative relocation deltas. Usually that works out ok since the
581 	 * relocate address is still positive, except when the batch is placed
582 	 * very low in the GTT. Ensure this doesn't happen.
583 	 *
584 	 * Note that actual hangs have only been observed on gen7, but for
585 	 * paranoia do it everywhere.
586 	 */
587 	if (i == batch_idx) {
588 		if (entry->relocation_count &&
589 		    !(ev->flags & EXEC_OBJECT_PINNED))
590 			ev->flags |= __EXEC_OBJECT_NEEDS_BIAS;
591 		if (eb->reloc_cache.has_fence)
592 			ev->flags |= EXEC_OBJECT_NEEDS_FENCE;
593 
594 		eb->batch = ev;
595 	}
596 
597 	if (eb_pin_vma(eb, entry, ev)) {
598 		if (entry->offset != vma->node.start) {
599 			entry->offset = vma->node.start | UPDATE;
600 			eb->args->flags |= __EXEC_HAS_RELOC;
601 		}
602 	} else {
603 		eb_unreserve_vma(ev);
604 		list_add_tail(&ev->bind_link, &eb->unbound);
605 	}
606 }
607 
608 static inline int use_cpu_reloc(const struct reloc_cache *cache,
609 				const struct drm_i915_gem_object *obj)
610 {
611 	if (!i915_gem_object_has_struct_page(obj))
612 		return false;
613 
614 	if (DBG_FORCE_RELOC == FORCE_CPU_RELOC)
615 		return true;
616 
617 	if (DBG_FORCE_RELOC == FORCE_GTT_RELOC)
618 		return false;
619 
620 	return (cache->has_llc ||
621 		obj->cache_dirty ||
622 		obj->cache_level != I915_CACHE_NONE);
623 }
624 
625 static int eb_reserve_vma(const struct i915_execbuffer *eb,
626 			  struct eb_vma *ev,
627 			  u64 pin_flags)
628 {
629 	struct drm_i915_gem_exec_object2 *entry = ev->exec;
630 	struct i915_vma *vma = ev->vma;
631 	int err;
632 
633 	if (drm_mm_node_allocated(&vma->node) &&
634 	    eb_vma_misplaced(entry, vma, ev->flags)) {
635 		err = i915_vma_unbind(vma);
636 		if (err)
637 			return err;
638 	}
639 
640 	err = i915_vma_pin(vma,
641 			   entry->pad_to_size, entry->alignment,
642 			   eb_pin_flags(entry, ev->flags) | pin_flags);
643 	if (err)
644 		return err;
645 
646 	if (entry->offset != vma->node.start) {
647 		entry->offset = vma->node.start | UPDATE;
648 		eb->args->flags |= __EXEC_HAS_RELOC;
649 	}
650 
651 	if (unlikely(ev->flags & EXEC_OBJECT_NEEDS_FENCE)) {
652 		err = i915_vma_pin_fence(vma);
653 		if (unlikely(err)) {
654 			i915_vma_unpin(vma);
655 			return err;
656 		}
657 
658 		if (vma->fence)
659 			ev->flags |= __EXEC_OBJECT_HAS_FENCE;
660 	}
661 
662 	ev->flags |= __EXEC_OBJECT_HAS_PIN;
663 	GEM_BUG_ON(eb_vma_misplaced(entry, vma, ev->flags));
664 
665 	return 0;
666 }
667 
668 static int eb_reserve(struct i915_execbuffer *eb)
669 {
670 	const unsigned int count = eb->buffer_count;
671 	unsigned int pin_flags = PIN_USER | PIN_NONBLOCK;
672 	struct list_head last;
673 	struct eb_vma *ev;
674 	unsigned int i, pass;
675 	int err = 0;
676 
677 	/*
678 	 * Attempt to pin all of the buffers into the GTT.
679 	 * This is done in 3 phases:
680 	 *
681 	 * 1a. Unbind all objects that do not match the GTT constraints for
682 	 *     the execbuffer (fenceable, mappable, alignment etc).
683 	 * 1b. Increment pin count for already bound objects.
684 	 * 2.  Bind new objects.
685 	 * 3.  Decrement pin count.
686 	 *
687 	 * This avoid unnecessary unbinding of later objects in order to make
688 	 * room for the earlier objects *unless* we need to defragment.
689 	 */
690 
691 	if (mutex_lock_interruptible(&eb->i915->drm.struct_mutex))
692 		return -EINTR;
693 
694 	pass = 0;
695 	do {
696 		list_for_each_entry(ev, &eb->unbound, bind_link) {
697 			err = eb_reserve_vma(eb, ev, pin_flags);
698 			if (err)
699 				break;
700 		}
701 		if (!(err == -ENOSPC || err == -EAGAIN))
702 			break;
703 
704 		/* Resort *all* the objects into priority order */
705 		INIT_LIST_HEAD(&eb->unbound);
706 		INIT_LIST_HEAD(&last);
707 		for (i = 0; i < count; i++) {
708 			unsigned int flags;
709 
710 			ev = &eb->vma[i];
711 			flags = ev->flags;
712 			if (flags & EXEC_OBJECT_PINNED &&
713 			    flags & __EXEC_OBJECT_HAS_PIN)
714 				continue;
715 
716 			eb_unreserve_vma(ev);
717 
718 			if (flags & EXEC_OBJECT_PINNED)
719 				/* Pinned must have their slot */
720 				list_add(&ev->bind_link, &eb->unbound);
721 			else if (flags & __EXEC_OBJECT_NEEDS_MAP)
722 				/* Map require the lowest 256MiB (aperture) */
723 				list_add_tail(&ev->bind_link, &eb->unbound);
724 			else if (!(flags & EXEC_OBJECT_SUPPORTS_48B_ADDRESS))
725 				/* Prioritise 4GiB region for restricted bo */
726 				list_add(&ev->bind_link, &last);
727 			else
728 				list_add_tail(&ev->bind_link, &last);
729 		}
730 		list_splice_tail(&last, &eb->unbound);
731 
732 		if (err == -EAGAIN) {
733 			mutex_unlock(&eb->i915->drm.struct_mutex);
734 			flush_workqueue(eb->i915->mm.userptr_wq);
735 			mutex_lock(&eb->i915->drm.struct_mutex);
736 			continue;
737 		}
738 
739 		switch (pass++) {
740 		case 0:
741 			break;
742 
743 		case 1:
744 			/* Too fragmented, unbind everything and retry */
745 			mutex_lock(&eb->context->vm->mutex);
746 			err = i915_gem_evict_vm(eb->context->vm);
747 			mutex_unlock(&eb->context->vm->mutex);
748 			if (err)
749 				goto unlock;
750 			break;
751 
752 		default:
753 			err = -ENOSPC;
754 			goto unlock;
755 		}
756 
757 		pin_flags = PIN_USER;
758 	} while (1);
759 
760 unlock:
761 	mutex_unlock(&eb->i915->drm.struct_mutex);
762 	return err;
763 }
764 
765 static unsigned int eb_batch_index(const struct i915_execbuffer *eb)
766 {
767 	if (eb->args->flags & I915_EXEC_BATCH_FIRST)
768 		return 0;
769 	else
770 		return eb->buffer_count - 1;
771 }
772 
773 static int eb_select_context(struct i915_execbuffer *eb)
774 {
775 	struct i915_gem_context *ctx;
776 
777 	ctx = i915_gem_context_lookup(eb->file->driver_priv, eb->args->rsvd1);
778 	if (unlikely(!ctx))
779 		return -ENOENT;
780 
781 	eb->gem_context = ctx;
782 	if (rcu_access_pointer(ctx->vm))
783 		eb->invalid_flags |= EXEC_OBJECT_NEEDS_GTT;
784 
785 	eb->context_flags = 0;
786 	if (test_bit(UCONTEXT_NO_ZEROMAP, &ctx->user_flags))
787 		eb->context_flags |= __EXEC_OBJECT_NEEDS_BIAS;
788 
789 	return 0;
790 }
791 
792 static int __eb_add_lut(struct i915_execbuffer *eb,
793 			u32 handle, struct i915_vma *vma)
794 {
795 	struct i915_gem_context *ctx = eb->gem_context;
796 	struct i915_lut_handle *lut;
797 	int err;
798 
799 	lut = i915_lut_handle_alloc();
800 	if (unlikely(!lut))
801 		return -ENOMEM;
802 
803 	i915_vma_get(vma);
804 	if (!atomic_fetch_inc(&vma->open_count))
805 		i915_vma_reopen(vma);
806 	lut->handle = handle;
807 	lut->ctx = ctx;
808 
809 	/* Check that the context hasn't been closed in the meantime */
810 	err = -EINTR;
811 	if (!mutex_lock_interruptible(&ctx->mutex)) {
812 		err = -ENOENT;
813 		if (likely(!i915_gem_context_is_closed(ctx)))
814 			err = radix_tree_insert(&ctx->handles_vma, handle, vma);
815 		if (err == 0) { /* And nor has this handle */
816 			struct drm_i915_gem_object *obj = vma->obj;
817 
818 			i915_gem_object_lock(obj);
819 			if (idr_find(&eb->file->object_idr, handle) == obj) {
820 				list_add(&lut->obj_link, &obj->lut_list);
821 			} else {
822 				radix_tree_delete(&ctx->handles_vma, handle);
823 				err = -ENOENT;
824 			}
825 			i915_gem_object_unlock(obj);
826 		}
827 		mutex_unlock(&ctx->mutex);
828 	}
829 	if (unlikely(err))
830 		goto err;
831 
832 	return 0;
833 
834 err:
835 	i915_vma_close(vma);
836 	i915_vma_put(vma);
837 	i915_lut_handle_free(lut);
838 	return err;
839 }
840 
841 static struct i915_vma *eb_lookup_vma(struct i915_execbuffer *eb, u32 handle)
842 {
843 	do {
844 		struct drm_i915_gem_object *obj;
845 		struct i915_vma *vma;
846 		int err;
847 
848 		rcu_read_lock();
849 		vma = radix_tree_lookup(&eb->gem_context->handles_vma, handle);
850 		if (likely(vma))
851 			vma = i915_vma_tryget(vma);
852 		rcu_read_unlock();
853 		if (likely(vma))
854 			return vma;
855 
856 		obj = i915_gem_object_lookup(eb->file, handle);
857 		if (unlikely(!obj))
858 			return ERR_PTR(-ENOENT);
859 
860 		vma = i915_vma_instance(obj, eb->context->vm, NULL);
861 		if (IS_ERR(vma)) {
862 			i915_gem_object_put(obj);
863 			return vma;
864 		}
865 
866 		err = __eb_add_lut(eb, handle, vma);
867 		if (likely(!err))
868 			return vma;
869 
870 		i915_gem_object_put(obj);
871 		if (err != -EEXIST)
872 			return ERR_PTR(err);
873 	} while (1);
874 }
875 
876 static int eb_lookup_vmas(struct i915_execbuffer *eb)
877 {
878 	unsigned int batch = eb_batch_index(eb);
879 	unsigned int i;
880 	int err = 0;
881 
882 	INIT_LIST_HEAD(&eb->relocs);
883 	INIT_LIST_HEAD(&eb->unbound);
884 
885 	for (i = 0; i < eb->buffer_count; i++) {
886 		struct i915_vma *vma;
887 
888 		vma = eb_lookup_vma(eb, eb->exec[i].handle);
889 		if (IS_ERR(vma)) {
890 			err = PTR_ERR(vma);
891 			break;
892 		}
893 
894 		err = eb_validate_vma(eb, &eb->exec[i], vma);
895 		if (unlikely(err)) {
896 			i915_vma_put(vma);
897 			break;
898 		}
899 
900 		eb_add_vma(eb, i, batch, vma);
901 	}
902 
903 	eb->vma[i].vma = NULL;
904 	return err;
905 }
906 
907 static struct eb_vma *
908 eb_get_vma(const struct i915_execbuffer *eb, unsigned long handle)
909 {
910 	if (eb->lut_size < 0) {
911 		if (handle >= -eb->lut_size)
912 			return NULL;
913 		return &eb->vma[handle];
914 	} else {
915 		struct hlist_head *head;
916 		struct eb_vma *ev;
917 
918 		head = &eb->buckets[hash_32(handle, eb->lut_size)];
919 		hlist_for_each_entry(ev, head, node) {
920 			if (ev->handle == handle)
921 				return ev;
922 		}
923 		return NULL;
924 	}
925 }
926 
927 static void eb_destroy(const struct i915_execbuffer *eb)
928 {
929 	GEM_BUG_ON(eb->reloc_cache.rq);
930 
931 	if (eb->array)
932 		eb_vma_array_put(eb->array);
933 
934 	if (eb->lut_size > 0)
935 		kfree(eb->buckets);
936 }
937 
938 static inline u64
939 relocation_target(const struct drm_i915_gem_relocation_entry *reloc,
940 		  const struct i915_vma *target)
941 {
942 	return gen8_canonical_addr((int)reloc->delta + target->node.start);
943 }
944 
945 static void reloc_cache_init(struct reloc_cache *cache,
946 			     struct drm_i915_private *i915)
947 {
948 	cache->page = -1;
949 	cache->vaddr = 0;
950 	/* Must be a variable in the struct to allow GCC to unroll. */
951 	cache->gen = INTEL_GEN(i915);
952 	cache->has_llc = HAS_LLC(i915);
953 	cache->use_64bit_reloc = HAS_64BIT_RELOC(i915);
954 	cache->has_fence = cache->gen < 4;
955 	cache->needs_unfenced = INTEL_INFO(i915)->unfenced_needs_alignment;
956 	cache->node.flags = 0;
957 	cache->rq = NULL;
958 	cache->target = NULL;
959 }
960 
961 static inline void *unmask_page(unsigned long p)
962 {
963 	return (void *)(uintptr_t)(p & PAGE_MASK);
964 }
965 
966 static inline unsigned int unmask_flags(unsigned long p)
967 {
968 	return p & ~PAGE_MASK;
969 }
970 
971 #define KMAP 0x4 /* after CLFLUSH_FLAGS */
972 
973 static inline struct i915_ggtt *cache_to_ggtt(struct reloc_cache *cache)
974 {
975 	struct drm_i915_private *i915 =
976 		container_of(cache, struct i915_execbuffer, reloc_cache)->i915;
977 	return &i915->ggtt;
978 }
979 
980 #define RELOC_TAIL 4
981 
982 static int reloc_gpu_chain(struct reloc_cache *cache)
983 {
984 	struct intel_gt_buffer_pool_node *pool;
985 	struct i915_request *rq = cache->rq;
986 	struct i915_vma *batch;
987 	u32 *cmd;
988 	int err;
989 
990 	pool = intel_gt_get_buffer_pool(rq->engine->gt, PAGE_SIZE);
991 	if (IS_ERR(pool))
992 		return PTR_ERR(pool);
993 
994 	batch = i915_vma_instance(pool->obj, rq->context->vm, NULL);
995 	if (IS_ERR(batch)) {
996 		err = PTR_ERR(batch);
997 		goto out_pool;
998 	}
999 
1000 	err = i915_vma_pin(batch, 0, 0, PIN_USER | PIN_NONBLOCK);
1001 	if (err)
1002 		goto out_pool;
1003 
1004 	GEM_BUG_ON(cache->rq_size + RELOC_TAIL > PAGE_SIZE  / sizeof(u32));
1005 	cmd = cache->rq_cmd + cache->rq_size;
1006 	*cmd++ = MI_ARB_CHECK;
1007 	if (cache->gen >= 8)
1008 		*cmd++ = MI_BATCH_BUFFER_START_GEN8;
1009 	else if (cache->gen >= 6)
1010 		*cmd++ = MI_BATCH_BUFFER_START;
1011 	else
1012 		*cmd++ = MI_BATCH_BUFFER_START | MI_BATCH_GTT;
1013 	*cmd++ = lower_32_bits(batch->node.start);
1014 	*cmd++ = upper_32_bits(batch->node.start); /* Always 0 for gen<8 */
1015 	i915_gem_object_flush_map(cache->rq_vma->obj);
1016 	i915_gem_object_unpin_map(cache->rq_vma->obj);
1017 	cache->rq_vma = NULL;
1018 
1019 	err = intel_gt_buffer_pool_mark_active(pool, rq);
1020 	if (err == 0) {
1021 		i915_vma_lock(batch);
1022 		err = i915_request_await_object(rq, batch->obj, false);
1023 		if (err == 0)
1024 			err = i915_vma_move_to_active(batch, rq, 0);
1025 		i915_vma_unlock(batch);
1026 	}
1027 	i915_vma_unpin(batch);
1028 	if (err)
1029 		goto out_pool;
1030 
1031 	cmd = i915_gem_object_pin_map(batch->obj,
1032 				      cache->has_llc ?
1033 				      I915_MAP_FORCE_WB :
1034 				      I915_MAP_FORCE_WC);
1035 	if (IS_ERR(cmd)) {
1036 		err = PTR_ERR(cmd);
1037 		goto out_pool;
1038 	}
1039 
1040 	/* Return with batch mapping (cmd) still pinned */
1041 	cache->rq_cmd = cmd;
1042 	cache->rq_size = 0;
1043 	cache->rq_vma = batch;
1044 
1045 out_pool:
1046 	intel_gt_buffer_pool_put(pool);
1047 	return err;
1048 }
1049 
1050 static unsigned int reloc_bb_flags(const struct reloc_cache *cache)
1051 {
1052 	return cache->gen > 5 ? 0 : I915_DISPATCH_SECURE;
1053 }
1054 
1055 static int reloc_gpu_flush(struct reloc_cache *cache)
1056 {
1057 	struct i915_request *rq;
1058 	int err;
1059 
1060 	rq = fetch_and_zero(&cache->rq);
1061 	if (!rq)
1062 		return 0;
1063 
1064 	if (cache->rq_vma) {
1065 		struct drm_i915_gem_object *obj = cache->rq_vma->obj;
1066 
1067 		GEM_BUG_ON(cache->rq_size >= obj->base.size / sizeof(u32));
1068 		cache->rq_cmd[cache->rq_size++] = MI_BATCH_BUFFER_END;
1069 
1070 		__i915_gem_object_flush_map(obj,
1071 					    0, sizeof(u32) * cache->rq_size);
1072 		i915_gem_object_unpin_map(obj);
1073 	}
1074 
1075 	err = 0;
1076 	if (rq->engine->emit_init_breadcrumb)
1077 		err = rq->engine->emit_init_breadcrumb(rq);
1078 	if (!err)
1079 		err = rq->engine->emit_bb_start(rq,
1080 						rq->batch->node.start,
1081 						PAGE_SIZE,
1082 						reloc_bb_flags(cache));
1083 	if (err)
1084 		i915_request_set_error_once(rq, err);
1085 
1086 	intel_gt_chipset_flush(rq->engine->gt);
1087 	i915_request_add(rq);
1088 
1089 	return err;
1090 }
1091 
1092 static void reloc_cache_reset(struct reloc_cache *cache)
1093 {
1094 	void *vaddr;
1095 
1096 	if (!cache->vaddr)
1097 		return;
1098 
1099 	vaddr = unmask_page(cache->vaddr);
1100 	if (cache->vaddr & KMAP) {
1101 		if (cache->vaddr & CLFLUSH_AFTER)
1102 			mb();
1103 
1104 		kunmap_atomic(vaddr);
1105 		i915_gem_object_finish_access((struct drm_i915_gem_object *)cache->node.mm);
1106 	} else {
1107 		struct i915_ggtt *ggtt = cache_to_ggtt(cache);
1108 
1109 		intel_gt_flush_ggtt_writes(ggtt->vm.gt);
1110 		io_mapping_unmap_atomic((void __iomem *)vaddr);
1111 
1112 		if (drm_mm_node_allocated(&cache->node)) {
1113 			ggtt->vm.clear_range(&ggtt->vm,
1114 					     cache->node.start,
1115 					     cache->node.size);
1116 			mutex_lock(&ggtt->vm.mutex);
1117 			drm_mm_remove_node(&cache->node);
1118 			mutex_unlock(&ggtt->vm.mutex);
1119 		} else {
1120 			i915_vma_unpin((struct i915_vma *)cache->node.mm);
1121 		}
1122 	}
1123 
1124 	cache->vaddr = 0;
1125 	cache->page = -1;
1126 }
1127 
1128 static void *reloc_kmap(struct drm_i915_gem_object *obj,
1129 			struct reloc_cache *cache,
1130 			unsigned long page)
1131 {
1132 	void *vaddr;
1133 
1134 	if (cache->vaddr) {
1135 		kunmap_atomic(unmask_page(cache->vaddr));
1136 	} else {
1137 		unsigned int flushes;
1138 		int err;
1139 
1140 		err = i915_gem_object_prepare_write(obj, &flushes);
1141 		if (err)
1142 			return ERR_PTR(err);
1143 
1144 		BUILD_BUG_ON(KMAP & CLFLUSH_FLAGS);
1145 		BUILD_BUG_ON((KMAP | CLFLUSH_FLAGS) & PAGE_MASK);
1146 
1147 		cache->vaddr = flushes | KMAP;
1148 		cache->node.mm = (void *)obj;
1149 		if (flushes)
1150 			mb();
1151 	}
1152 
1153 	vaddr = kmap_atomic(i915_gem_object_get_dirty_page(obj, page));
1154 	cache->vaddr = unmask_flags(cache->vaddr) | (unsigned long)vaddr;
1155 	cache->page = page;
1156 
1157 	return vaddr;
1158 }
1159 
1160 static void *reloc_iomap(struct drm_i915_gem_object *obj,
1161 			 struct reloc_cache *cache,
1162 			 unsigned long page)
1163 {
1164 	struct i915_ggtt *ggtt = cache_to_ggtt(cache);
1165 	unsigned long offset;
1166 	void *vaddr;
1167 
1168 	if (cache->vaddr) {
1169 		intel_gt_flush_ggtt_writes(ggtt->vm.gt);
1170 		io_mapping_unmap_atomic((void __force __iomem *) unmask_page(cache->vaddr));
1171 	} else {
1172 		struct i915_vma *vma;
1173 		int err;
1174 
1175 		if (i915_gem_object_is_tiled(obj))
1176 			return ERR_PTR(-EINVAL);
1177 
1178 		if (use_cpu_reloc(cache, obj))
1179 			return NULL;
1180 
1181 		i915_gem_object_lock(obj);
1182 		err = i915_gem_object_set_to_gtt_domain(obj, true);
1183 		i915_gem_object_unlock(obj);
1184 		if (err)
1185 			return ERR_PTR(err);
1186 
1187 		vma = i915_gem_object_ggtt_pin(obj, NULL, 0, 0,
1188 					       PIN_MAPPABLE |
1189 					       PIN_NONBLOCK /* NOWARN */ |
1190 					       PIN_NOEVICT);
1191 		if (IS_ERR(vma)) {
1192 			memset(&cache->node, 0, sizeof(cache->node));
1193 			mutex_lock(&ggtt->vm.mutex);
1194 			err = drm_mm_insert_node_in_range
1195 				(&ggtt->vm.mm, &cache->node,
1196 				 PAGE_SIZE, 0, I915_COLOR_UNEVICTABLE,
1197 				 0, ggtt->mappable_end,
1198 				 DRM_MM_INSERT_LOW);
1199 			mutex_unlock(&ggtt->vm.mutex);
1200 			if (err) /* no inactive aperture space, use cpu reloc */
1201 				return NULL;
1202 		} else {
1203 			cache->node.start = vma->node.start;
1204 			cache->node.mm = (void *)vma;
1205 		}
1206 	}
1207 
1208 	offset = cache->node.start;
1209 	if (drm_mm_node_allocated(&cache->node)) {
1210 		ggtt->vm.insert_page(&ggtt->vm,
1211 				     i915_gem_object_get_dma_address(obj, page),
1212 				     offset, I915_CACHE_NONE, 0);
1213 	} else {
1214 		offset += page << PAGE_SHIFT;
1215 	}
1216 
1217 	vaddr = (void __force *)io_mapping_map_atomic_wc(&ggtt->iomap,
1218 							 offset);
1219 	cache->page = page;
1220 	cache->vaddr = (unsigned long)vaddr;
1221 
1222 	return vaddr;
1223 }
1224 
1225 static void *reloc_vaddr(struct drm_i915_gem_object *obj,
1226 			 struct reloc_cache *cache,
1227 			 unsigned long page)
1228 {
1229 	void *vaddr;
1230 
1231 	if (cache->page == page) {
1232 		vaddr = unmask_page(cache->vaddr);
1233 	} else {
1234 		vaddr = NULL;
1235 		if ((cache->vaddr & KMAP) == 0)
1236 			vaddr = reloc_iomap(obj, cache, page);
1237 		if (!vaddr)
1238 			vaddr = reloc_kmap(obj, cache, page);
1239 	}
1240 
1241 	return vaddr;
1242 }
1243 
1244 static void clflush_write32(u32 *addr, u32 value, unsigned int flushes)
1245 {
1246 	if (unlikely(flushes & (CLFLUSH_BEFORE | CLFLUSH_AFTER))) {
1247 		if (flushes & CLFLUSH_BEFORE) {
1248 			clflushopt(addr);
1249 			mb();
1250 		}
1251 
1252 		*addr = value;
1253 
1254 		/*
1255 		 * Writes to the same cacheline are serialised by the CPU
1256 		 * (including clflush). On the write path, we only require
1257 		 * that it hits memory in an orderly fashion and place
1258 		 * mb barriers at the start and end of the relocation phase
1259 		 * to ensure ordering of clflush wrt to the system.
1260 		 */
1261 		if (flushes & CLFLUSH_AFTER)
1262 			clflushopt(addr);
1263 	} else
1264 		*addr = value;
1265 }
1266 
1267 static int reloc_move_to_gpu(struct i915_request *rq, struct i915_vma *vma)
1268 {
1269 	struct drm_i915_gem_object *obj = vma->obj;
1270 	int err;
1271 
1272 	i915_vma_lock(vma);
1273 
1274 	if (obj->cache_dirty & ~obj->cache_coherent)
1275 		i915_gem_clflush_object(obj, 0);
1276 	obj->write_domain = 0;
1277 
1278 	err = i915_request_await_object(rq, vma->obj, true);
1279 	if (err == 0)
1280 		err = i915_vma_move_to_active(vma, rq, EXEC_OBJECT_WRITE);
1281 
1282 	i915_vma_unlock(vma);
1283 
1284 	return err;
1285 }
1286 
1287 static int __reloc_gpu_alloc(struct i915_execbuffer *eb,
1288 			     struct intel_engine_cs *engine,
1289 			     unsigned int len)
1290 {
1291 	struct reloc_cache *cache = &eb->reloc_cache;
1292 	struct intel_gt_buffer_pool_node *pool;
1293 	struct i915_request *rq;
1294 	struct i915_vma *batch;
1295 	u32 *cmd;
1296 	int err;
1297 
1298 	pool = intel_gt_get_buffer_pool(engine->gt, PAGE_SIZE);
1299 	if (IS_ERR(pool))
1300 		return PTR_ERR(pool);
1301 
1302 	cmd = i915_gem_object_pin_map(pool->obj,
1303 				      cache->has_llc ?
1304 				      I915_MAP_FORCE_WB :
1305 				      I915_MAP_FORCE_WC);
1306 	if (IS_ERR(cmd)) {
1307 		err = PTR_ERR(cmd);
1308 		goto out_pool;
1309 	}
1310 
1311 	batch = i915_vma_instance(pool->obj, eb->context->vm, NULL);
1312 	if (IS_ERR(batch)) {
1313 		err = PTR_ERR(batch);
1314 		goto err_unmap;
1315 	}
1316 
1317 	err = i915_vma_pin(batch, 0, 0, PIN_USER | PIN_NONBLOCK);
1318 	if (err)
1319 		goto err_unmap;
1320 
1321 	if (engine == eb->context->engine) {
1322 		rq = i915_request_create(eb->context);
1323 	} else {
1324 		struct intel_context *ce;
1325 
1326 		ce = intel_context_create(engine);
1327 		if (IS_ERR(ce)) {
1328 			err = PTR_ERR(ce);
1329 			goto err_unpin;
1330 		}
1331 
1332 		i915_vm_put(ce->vm);
1333 		ce->vm = i915_vm_get(eb->context->vm);
1334 
1335 		rq = intel_context_create_request(ce);
1336 		intel_context_put(ce);
1337 	}
1338 	if (IS_ERR(rq)) {
1339 		err = PTR_ERR(rq);
1340 		goto err_unpin;
1341 	}
1342 
1343 	err = intel_gt_buffer_pool_mark_active(pool, rq);
1344 	if (err)
1345 		goto err_request;
1346 
1347 	i915_vma_lock(batch);
1348 	err = i915_request_await_object(rq, batch->obj, false);
1349 	if (err == 0)
1350 		err = i915_vma_move_to_active(batch, rq, 0);
1351 	i915_vma_unlock(batch);
1352 	if (err)
1353 		goto skip_request;
1354 
1355 	rq->batch = batch;
1356 	i915_vma_unpin(batch);
1357 
1358 	cache->rq = rq;
1359 	cache->rq_cmd = cmd;
1360 	cache->rq_size = 0;
1361 	cache->rq_vma = batch;
1362 
1363 	/* Return with batch mapping (cmd) still pinned */
1364 	goto out_pool;
1365 
1366 skip_request:
1367 	i915_request_set_error_once(rq, err);
1368 err_request:
1369 	i915_request_add(rq);
1370 err_unpin:
1371 	i915_vma_unpin(batch);
1372 err_unmap:
1373 	i915_gem_object_unpin_map(pool->obj);
1374 out_pool:
1375 	intel_gt_buffer_pool_put(pool);
1376 	return err;
1377 }
1378 
1379 static bool reloc_can_use_engine(const struct intel_engine_cs *engine)
1380 {
1381 	return engine->class != VIDEO_DECODE_CLASS || !IS_GEN(engine->i915, 6);
1382 }
1383 
1384 static u32 *reloc_gpu(struct i915_execbuffer *eb,
1385 		      struct i915_vma *vma,
1386 		      unsigned int len)
1387 {
1388 	struct reloc_cache *cache = &eb->reloc_cache;
1389 	u32 *cmd;
1390 	int err;
1391 
1392 	if (unlikely(!cache->rq)) {
1393 		struct intel_engine_cs *engine = eb->engine;
1394 
1395 		if (!reloc_can_use_engine(engine)) {
1396 			engine = engine->gt->engine_class[COPY_ENGINE_CLASS][0];
1397 			if (!engine)
1398 				return ERR_PTR(-ENODEV);
1399 		}
1400 
1401 		err = __reloc_gpu_alloc(eb, engine, len);
1402 		if (unlikely(err))
1403 			return ERR_PTR(err);
1404 	}
1405 
1406 	if (vma != cache->target) {
1407 		err = reloc_move_to_gpu(cache->rq, vma);
1408 		if (unlikely(err)) {
1409 			i915_request_set_error_once(cache->rq, err);
1410 			return ERR_PTR(err);
1411 		}
1412 
1413 		cache->target = vma;
1414 	}
1415 
1416 	if (unlikely(cache->rq_size + len >
1417 		     PAGE_SIZE / sizeof(u32) - RELOC_TAIL)) {
1418 		err = reloc_gpu_chain(cache);
1419 		if (unlikely(err)) {
1420 			i915_request_set_error_once(cache->rq, err);
1421 			return ERR_PTR(err);
1422 		}
1423 	}
1424 
1425 	GEM_BUG_ON(cache->rq_size + len >= PAGE_SIZE  / sizeof(u32));
1426 	cmd = cache->rq_cmd + cache->rq_size;
1427 	cache->rq_size += len;
1428 
1429 	return cmd;
1430 }
1431 
1432 static inline bool use_reloc_gpu(struct i915_vma *vma)
1433 {
1434 	if (DBG_FORCE_RELOC == FORCE_GPU_RELOC)
1435 		return true;
1436 
1437 	if (DBG_FORCE_RELOC)
1438 		return false;
1439 
1440 	return !dma_resv_test_signaled_rcu(vma->resv, true);
1441 }
1442 
1443 static unsigned long vma_phys_addr(struct i915_vma *vma, u32 offset)
1444 {
1445 	struct page *page;
1446 	unsigned long addr;
1447 
1448 	GEM_BUG_ON(vma->pages != vma->obj->mm.pages);
1449 
1450 	page = i915_gem_object_get_page(vma->obj, offset >> PAGE_SHIFT);
1451 	addr = PFN_PHYS(page_to_pfn(page));
1452 	GEM_BUG_ON(overflows_type(addr, u32)); /* expected dma32 */
1453 
1454 	return addr + offset_in_page(offset);
1455 }
1456 
1457 static bool __reloc_entry_gpu(struct i915_execbuffer *eb,
1458 			      struct i915_vma *vma,
1459 			      u64 offset,
1460 			      u64 target_addr)
1461 {
1462 	const unsigned int gen = eb->reloc_cache.gen;
1463 	unsigned int len;
1464 	u32 *batch;
1465 	u64 addr;
1466 
1467 	if (gen >= 8)
1468 		len = offset & 7 ? 8 : 5;
1469 	else if (gen >= 4)
1470 		len = 4;
1471 	else
1472 		len = 3;
1473 
1474 	batch = reloc_gpu(eb, vma, len);
1475 	if (IS_ERR(batch))
1476 		return false;
1477 
1478 	addr = gen8_canonical_addr(vma->node.start + offset);
1479 	if (gen >= 8) {
1480 		if (offset & 7) {
1481 			*batch++ = MI_STORE_DWORD_IMM_GEN4;
1482 			*batch++ = lower_32_bits(addr);
1483 			*batch++ = upper_32_bits(addr);
1484 			*batch++ = lower_32_bits(target_addr);
1485 
1486 			addr = gen8_canonical_addr(addr + 4);
1487 
1488 			*batch++ = MI_STORE_DWORD_IMM_GEN4;
1489 			*batch++ = lower_32_bits(addr);
1490 			*batch++ = upper_32_bits(addr);
1491 			*batch++ = upper_32_bits(target_addr);
1492 		} else {
1493 			*batch++ = (MI_STORE_DWORD_IMM_GEN4 | (1 << 21)) + 1;
1494 			*batch++ = lower_32_bits(addr);
1495 			*batch++ = upper_32_bits(addr);
1496 			*batch++ = lower_32_bits(target_addr);
1497 			*batch++ = upper_32_bits(target_addr);
1498 		}
1499 	} else if (gen >= 6) {
1500 		*batch++ = MI_STORE_DWORD_IMM_GEN4;
1501 		*batch++ = 0;
1502 		*batch++ = addr;
1503 		*batch++ = target_addr;
1504 	} else if (IS_I965G(eb->i915)) {
1505 		*batch++ = MI_STORE_DWORD_IMM_GEN4;
1506 		*batch++ = 0;
1507 		*batch++ = vma_phys_addr(vma, offset);
1508 		*batch++ = target_addr;
1509 	} else if (gen >= 4) {
1510 		*batch++ = MI_STORE_DWORD_IMM_GEN4 | MI_USE_GGTT;
1511 		*batch++ = 0;
1512 		*batch++ = addr;
1513 		*batch++ = target_addr;
1514 	} else if (gen >= 3 &&
1515 		   !(IS_I915G(eb->i915) || IS_I915GM(eb->i915))) {
1516 		*batch++ = MI_STORE_DWORD_IMM | MI_MEM_VIRTUAL;
1517 		*batch++ = addr;
1518 		*batch++ = target_addr;
1519 	} else {
1520 		*batch++ = MI_STORE_DWORD_IMM;
1521 		*batch++ = vma_phys_addr(vma, offset);
1522 		*batch++ = target_addr;
1523 	}
1524 
1525 	return true;
1526 }
1527 
1528 static bool reloc_entry_gpu(struct i915_execbuffer *eb,
1529 			    struct i915_vma *vma,
1530 			    u64 offset,
1531 			    u64 target_addr)
1532 {
1533 	if (eb->reloc_cache.vaddr)
1534 		return false;
1535 
1536 	if (!use_reloc_gpu(vma))
1537 		return false;
1538 
1539 	return __reloc_entry_gpu(eb, vma, offset, target_addr);
1540 }
1541 
1542 static u64
1543 relocate_entry(struct i915_vma *vma,
1544 	       const struct drm_i915_gem_relocation_entry *reloc,
1545 	       struct i915_execbuffer *eb,
1546 	       const struct i915_vma *target)
1547 {
1548 	u64 target_addr = relocation_target(reloc, target);
1549 	u64 offset = reloc->offset;
1550 
1551 	if (!reloc_entry_gpu(eb, vma, offset, target_addr)) {
1552 		bool wide = eb->reloc_cache.use_64bit_reloc;
1553 		void *vaddr;
1554 
1555 repeat:
1556 		vaddr = reloc_vaddr(vma->obj,
1557 				    &eb->reloc_cache,
1558 				    offset >> PAGE_SHIFT);
1559 		if (IS_ERR(vaddr))
1560 			return PTR_ERR(vaddr);
1561 
1562 		GEM_BUG_ON(!IS_ALIGNED(offset, sizeof(u32)));
1563 		clflush_write32(vaddr + offset_in_page(offset),
1564 				lower_32_bits(target_addr),
1565 				eb->reloc_cache.vaddr);
1566 
1567 		if (wide) {
1568 			offset += sizeof(u32);
1569 			target_addr >>= 32;
1570 			wide = false;
1571 			goto repeat;
1572 		}
1573 	}
1574 
1575 	return target->node.start | UPDATE;
1576 }
1577 
1578 static u64
1579 eb_relocate_entry(struct i915_execbuffer *eb,
1580 		  struct eb_vma *ev,
1581 		  const struct drm_i915_gem_relocation_entry *reloc)
1582 {
1583 	struct drm_i915_private *i915 = eb->i915;
1584 	struct eb_vma *target;
1585 	int err;
1586 
1587 	/* we've already hold a reference to all valid objects */
1588 	target = eb_get_vma(eb, reloc->target_handle);
1589 	if (unlikely(!target))
1590 		return -ENOENT;
1591 
1592 	/* Validate that the target is in a valid r/w GPU domain */
1593 	if (unlikely(reloc->write_domain & (reloc->write_domain - 1))) {
1594 		drm_dbg(&i915->drm, "reloc with multiple write domains: "
1595 			  "target %d offset %d "
1596 			  "read %08x write %08x",
1597 			  reloc->target_handle,
1598 			  (int) reloc->offset,
1599 			  reloc->read_domains,
1600 			  reloc->write_domain);
1601 		return -EINVAL;
1602 	}
1603 	if (unlikely((reloc->write_domain | reloc->read_domains)
1604 		     & ~I915_GEM_GPU_DOMAINS)) {
1605 		drm_dbg(&i915->drm, "reloc with read/write non-GPU domains: "
1606 			  "target %d offset %d "
1607 			  "read %08x write %08x",
1608 			  reloc->target_handle,
1609 			  (int) reloc->offset,
1610 			  reloc->read_domains,
1611 			  reloc->write_domain);
1612 		return -EINVAL;
1613 	}
1614 
1615 	if (reloc->write_domain) {
1616 		target->flags |= EXEC_OBJECT_WRITE;
1617 
1618 		/*
1619 		 * Sandybridge PPGTT errata: We need a global gtt mapping
1620 		 * for MI and pipe_control writes because the gpu doesn't
1621 		 * properly redirect them through the ppgtt for non_secure
1622 		 * batchbuffers.
1623 		 */
1624 		if (reloc->write_domain == I915_GEM_DOMAIN_INSTRUCTION &&
1625 		    IS_GEN(eb->i915, 6)) {
1626 			err = i915_vma_bind(target->vma,
1627 					    target->vma->obj->cache_level,
1628 					    PIN_GLOBAL, NULL);
1629 			if (WARN_ONCE(err,
1630 				      "Unexpected failure to bind target VMA!"))
1631 				return err;
1632 		}
1633 	}
1634 
1635 	/*
1636 	 * If the relocation already has the right value in it, no
1637 	 * more work needs to be done.
1638 	 */
1639 	if (!DBG_FORCE_RELOC &&
1640 	    gen8_canonical_addr(target->vma->node.start) == reloc->presumed_offset)
1641 		return 0;
1642 
1643 	/* Check that the relocation address is valid... */
1644 	if (unlikely(reloc->offset >
1645 		     ev->vma->size - (eb->reloc_cache.use_64bit_reloc ? 8 : 4))) {
1646 		drm_dbg(&i915->drm, "Relocation beyond object bounds: "
1647 			  "target %d offset %d size %d.\n",
1648 			  reloc->target_handle,
1649 			  (int)reloc->offset,
1650 			  (int)ev->vma->size);
1651 		return -EINVAL;
1652 	}
1653 	if (unlikely(reloc->offset & 3)) {
1654 		drm_dbg(&i915->drm, "Relocation not 4-byte aligned: "
1655 			  "target %d offset %d.\n",
1656 			  reloc->target_handle,
1657 			  (int)reloc->offset);
1658 		return -EINVAL;
1659 	}
1660 
1661 	/*
1662 	 * If we write into the object, we need to force the synchronisation
1663 	 * barrier, either with an asynchronous clflush or if we executed the
1664 	 * patching using the GPU (though that should be serialised by the
1665 	 * timeline). To be completely sure, and since we are required to
1666 	 * do relocations we are already stalling, disable the user's opt
1667 	 * out of our synchronisation.
1668 	 */
1669 	ev->flags &= ~EXEC_OBJECT_ASYNC;
1670 
1671 	/* and update the user's relocation entry */
1672 	return relocate_entry(ev->vma, reloc, eb, target->vma);
1673 }
1674 
1675 static int eb_relocate_vma(struct i915_execbuffer *eb, struct eb_vma *ev)
1676 {
1677 #define N_RELOC(x) ((x) / sizeof(struct drm_i915_gem_relocation_entry))
1678 	struct drm_i915_gem_relocation_entry stack[N_RELOC(512)];
1679 	const struct drm_i915_gem_exec_object2 *entry = ev->exec;
1680 	struct drm_i915_gem_relocation_entry __user *urelocs =
1681 		u64_to_user_ptr(entry->relocs_ptr);
1682 	unsigned long remain = entry->relocation_count;
1683 
1684 	if (unlikely(remain > N_RELOC(ULONG_MAX)))
1685 		return -EINVAL;
1686 
1687 	/*
1688 	 * We must check that the entire relocation array is safe
1689 	 * to read. However, if the array is not writable the user loses
1690 	 * the updated relocation values.
1691 	 */
1692 	if (unlikely(!access_ok(urelocs, remain * sizeof(*urelocs))))
1693 		return -EFAULT;
1694 
1695 	do {
1696 		struct drm_i915_gem_relocation_entry *r = stack;
1697 		unsigned int count =
1698 			min_t(unsigned long, remain, ARRAY_SIZE(stack));
1699 		unsigned int copied;
1700 
1701 		/*
1702 		 * This is the fast path and we cannot handle a pagefault
1703 		 * whilst holding the struct mutex lest the user pass in the
1704 		 * relocations contained within a mmaped bo. For in such a case
1705 		 * we, the page fault handler would call i915_gem_fault() and
1706 		 * we would try to acquire the struct mutex again. Obviously
1707 		 * this is bad and so lockdep complains vehemently.
1708 		 */
1709 		copied = __copy_from_user(r, urelocs, count * sizeof(r[0]));
1710 		if (unlikely(copied)) {
1711 			remain = -EFAULT;
1712 			goto out;
1713 		}
1714 
1715 		remain -= count;
1716 		do {
1717 			u64 offset = eb_relocate_entry(eb, ev, r);
1718 
1719 			if (likely(offset == 0)) {
1720 			} else if ((s64)offset < 0) {
1721 				remain = (int)offset;
1722 				goto out;
1723 			} else {
1724 				/*
1725 				 * Note that reporting an error now
1726 				 * leaves everything in an inconsistent
1727 				 * state as we have *already* changed
1728 				 * the relocation value inside the
1729 				 * object. As we have not changed the
1730 				 * reloc.presumed_offset or will not
1731 				 * change the execobject.offset, on the
1732 				 * call we may not rewrite the value
1733 				 * inside the object, leaving it
1734 				 * dangling and causing a GPU hang. Unless
1735 				 * userspace dynamically rebuilds the
1736 				 * relocations on each execbuf rather than
1737 				 * presume a static tree.
1738 				 *
1739 				 * We did previously check if the relocations
1740 				 * were writable (access_ok), an error now
1741 				 * would be a strange race with mprotect,
1742 				 * having already demonstrated that we
1743 				 * can read from this userspace address.
1744 				 */
1745 				offset = gen8_canonical_addr(offset & ~UPDATE);
1746 				__put_user(offset,
1747 					   &urelocs[r - stack].presumed_offset);
1748 			}
1749 		} while (r++, --count);
1750 		urelocs += ARRAY_SIZE(stack);
1751 	} while (remain);
1752 out:
1753 	reloc_cache_reset(&eb->reloc_cache);
1754 	return remain;
1755 }
1756 
1757 static int eb_relocate(struct i915_execbuffer *eb)
1758 {
1759 	int err;
1760 
1761 	err = eb_lookup_vmas(eb);
1762 	if (err)
1763 		return err;
1764 
1765 	if (!list_empty(&eb->unbound)) {
1766 		err = eb_reserve(eb);
1767 		if (err)
1768 			return err;
1769 	}
1770 
1771 	/* The objects are in their final locations, apply the relocations. */
1772 	if (eb->args->flags & __EXEC_HAS_RELOC) {
1773 		struct eb_vma *ev;
1774 		int flush;
1775 
1776 		list_for_each_entry(ev, &eb->relocs, reloc_link) {
1777 			err = eb_relocate_vma(eb, ev);
1778 			if (err)
1779 				break;
1780 		}
1781 
1782 		flush = reloc_gpu_flush(&eb->reloc_cache);
1783 		if (!err)
1784 			err = flush;
1785 	}
1786 
1787 	return err;
1788 }
1789 
1790 static int eb_move_to_gpu(struct i915_execbuffer *eb)
1791 {
1792 	const unsigned int count = eb->buffer_count;
1793 	struct ww_acquire_ctx acquire;
1794 	unsigned int i;
1795 	int err = 0;
1796 
1797 	ww_acquire_init(&acquire, &reservation_ww_class);
1798 
1799 	for (i = 0; i < count; i++) {
1800 		struct eb_vma *ev = &eb->vma[i];
1801 		struct i915_vma *vma = ev->vma;
1802 
1803 		err = ww_mutex_lock_interruptible(&vma->resv->lock, &acquire);
1804 		if (err == -EDEADLK) {
1805 			GEM_BUG_ON(i == 0);
1806 			do {
1807 				int j = i - 1;
1808 
1809 				ww_mutex_unlock(&eb->vma[j].vma->resv->lock);
1810 
1811 				swap(eb->vma[i],  eb->vma[j]);
1812 			} while (--i);
1813 
1814 			err = ww_mutex_lock_slow_interruptible(&vma->resv->lock,
1815 							       &acquire);
1816 		}
1817 		if (err)
1818 			break;
1819 	}
1820 	ww_acquire_done(&acquire);
1821 
1822 	while (i--) {
1823 		struct eb_vma *ev = &eb->vma[i];
1824 		struct i915_vma *vma = ev->vma;
1825 		unsigned int flags = ev->flags;
1826 		struct drm_i915_gem_object *obj = vma->obj;
1827 
1828 		assert_vma_held(vma);
1829 
1830 		if (flags & EXEC_OBJECT_CAPTURE) {
1831 			struct i915_capture_list *capture;
1832 
1833 			capture = kmalloc(sizeof(*capture), GFP_KERNEL);
1834 			if (capture) {
1835 				capture->next = eb->request->capture_list;
1836 				capture->vma = vma;
1837 				eb->request->capture_list = capture;
1838 			}
1839 		}
1840 
1841 		/*
1842 		 * If the GPU is not _reading_ through the CPU cache, we need
1843 		 * to make sure that any writes (both previous GPU writes from
1844 		 * before a change in snooping levels and normal CPU writes)
1845 		 * caught in that cache are flushed to main memory.
1846 		 *
1847 		 * We want to say
1848 		 *   obj->cache_dirty &&
1849 		 *   !(obj->cache_coherent & I915_BO_CACHE_COHERENT_FOR_READ)
1850 		 * but gcc's optimiser doesn't handle that as well and emits
1851 		 * two jumps instead of one. Maybe one day...
1852 		 */
1853 		if (unlikely(obj->cache_dirty & ~obj->cache_coherent)) {
1854 			if (i915_gem_clflush_object(obj, 0))
1855 				flags &= ~EXEC_OBJECT_ASYNC;
1856 		}
1857 
1858 		if (err == 0 && !(flags & EXEC_OBJECT_ASYNC)) {
1859 			err = i915_request_await_object
1860 				(eb->request, obj, flags & EXEC_OBJECT_WRITE);
1861 		}
1862 
1863 		if (err == 0)
1864 			err = i915_vma_move_to_active(vma, eb->request, flags);
1865 
1866 		i915_vma_unlock(vma);
1867 		eb_unreserve_vma(ev);
1868 	}
1869 	ww_acquire_fini(&acquire);
1870 
1871 	eb_vma_array_put(fetch_and_zero(&eb->array));
1872 
1873 	if (unlikely(err))
1874 		goto err_skip;
1875 
1876 	/* Unconditionally flush any chipset caches (for streaming writes). */
1877 	intel_gt_chipset_flush(eb->engine->gt);
1878 	return 0;
1879 
1880 err_skip:
1881 	i915_request_set_error_once(eb->request, err);
1882 	return err;
1883 }
1884 
1885 static int i915_gem_check_execbuffer(struct drm_i915_gem_execbuffer2 *exec)
1886 {
1887 	if (exec->flags & __I915_EXEC_ILLEGAL_FLAGS)
1888 		return -EINVAL;
1889 
1890 	/* Kernel clipping was a DRI1 misfeature */
1891 	if (!(exec->flags & I915_EXEC_FENCE_ARRAY)) {
1892 		if (exec->num_cliprects || exec->cliprects_ptr)
1893 			return -EINVAL;
1894 	}
1895 
1896 	if (exec->DR4 == 0xffffffff) {
1897 		DRM_DEBUG("UXA submitting garbage DR4, fixing up\n");
1898 		exec->DR4 = 0;
1899 	}
1900 	if (exec->DR1 || exec->DR4)
1901 		return -EINVAL;
1902 
1903 	if ((exec->batch_start_offset | exec->batch_len) & 0x7)
1904 		return -EINVAL;
1905 
1906 	return 0;
1907 }
1908 
1909 static int i915_reset_gen7_sol_offsets(struct i915_request *rq)
1910 {
1911 	u32 *cs;
1912 	int i;
1913 
1914 	if (!IS_GEN(rq->i915, 7) || rq->engine->id != RCS0) {
1915 		drm_dbg(&rq->i915->drm, "sol reset is gen7/rcs only\n");
1916 		return -EINVAL;
1917 	}
1918 
1919 	cs = intel_ring_begin(rq, 4 * 2 + 2);
1920 	if (IS_ERR(cs))
1921 		return PTR_ERR(cs);
1922 
1923 	*cs++ = MI_LOAD_REGISTER_IMM(4);
1924 	for (i = 0; i < 4; i++) {
1925 		*cs++ = i915_mmio_reg_offset(GEN7_SO_WRITE_OFFSET(i));
1926 		*cs++ = 0;
1927 	}
1928 	*cs++ = MI_NOOP;
1929 	intel_ring_advance(rq, cs);
1930 
1931 	return 0;
1932 }
1933 
1934 static struct i915_vma *
1935 shadow_batch_pin(struct drm_i915_gem_object *obj,
1936 		 struct i915_address_space *vm,
1937 		 unsigned int flags)
1938 {
1939 	struct i915_vma *vma;
1940 	int err;
1941 
1942 	vma = i915_vma_instance(obj, vm, NULL);
1943 	if (IS_ERR(vma))
1944 		return vma;
1945 
1946 	err = i915_vma_pin(vma, 0, 0, flags);
1947 	if (err)
1948 		return ERR_PTR(err);
1949 
1950 	return vma;
1951 }
1952 
1953 struct eb_parse_work {
1954 	struct dma_fence_work base;
1955 	struct intel_engine_cs *engine;
1956 	struct i915_vma *batch;
1957 	struct i915_vma *shadow;
1958 	struct i915_vma *trampoline;
1959 	unsigned int batch_offset;
1960 	unsigned int batch_length;
1961 };
1962 
1963 static int __eb_parse(struct dma_fence_work *work)
1964 {
1965 	struct eb_parse_work *pw = container_of(work, typeof(*pw), base);
1966 
1967 	return intel_engine_cmd_parser(pw->engine,
1968 				       pw->batch,
1969 				       pw->batch_offset,
1970 				       pw->batch_length,
1971 				       pw->shadow,
1972 				       pw->trampoline);
1973 }
1974 
1975 static void __eb_parse_release(struct dma_fence_work *work)
1976 {
1977 	struct eb_parse_work *pw = container_of(work, typeof(*pw), base);
1978 
1979 	if (pw->trampoline)
1980 		i915_active_release(&pw->trampoline->active);
1981 	i915_active_release(&pw->shadow->active);
1982 	i915_active_release(&pw->batch->active);
1983 }
1984 
1985 static const struct dma_fence_work_ops eb_parse_ops = {
1986 	.name = "eb_parse",
1987 	.work = __eb_parse,
1988 	.release = __eb_parse_release,
1989 };
1990 
1991 static inline int
1992 __parser_mark_active(struct i915_vma *vma,
1993 		     struct intel_timeline *tl,
1994 		     struct dma_fence *fence)
1995 {
1996 	struct intel_gt_buffer_pool_node *node = vma->private;
1997 
1998 	return i915_active_ref(&node->active, tl, fence);
1999 }
2000 
2001 static int
2002 parser_mark_active(struct eb_parse_work *pw, struct intel_timeline *tl)
2003 {
2004 	int err;
2005 
2006 	mutex_lock(&tl->mutex);
2007 
2008 	err = __parser_mark_active(pw->shadow, tl, &pw->base.dma);
2009 	if (err)
2010 		goto unlock;
2011 
2012 	if (pw->trampoline) {
2013 		err = __parser_mark_active(pw->trampoline, tl, &pw->base.dma);
2014 		if (err)
2015 			goto unlock;
2016 	}
2017 
2018 unlock:
2019 	mutex_unlock(&tl->mutex);
2020 	return err;
2021 }
2022 
2023 static int eb_parse_pipeline(struct i915_execbuffer *eb,
2024 			     struct i915_vma *shadow,
2025 			     struct i915_vma *trampoline)
2026 {
2027 	struct eb_parse_work *pw;
2028 	int err;
2029 
2030 	pw = kzalloc(sizeof(*pw), GFP_KERNEL);
2031 	if (!pw)
2032 		return -ENOMEM;
2033 
2034 	err = i915_active_acquire(&eb->batch->vma->active);
2035 	if (err)
2036 		goto err_free;
2037 
2038 	err = i915_active_acquire(&shadow->active);
2039 	if (err)
2040 		goto err_batch;
2041 
2042 	if (trampoline) {
2043 		err = i915_active_acquire(&trampoline->active);
2044 		if (err)
2045 			goto err_shadow;
2046 	}
2047 
2048 	dma_fence_work_init(&pw->base, &eb_parse_ops);
2049 
2050 	pw->engine = eb->engine;
2051 	pw->batch = eb->batch->vma;
2052 	pw->batch_offset = eb->batch_start_offset;
2053 	pw->batch_length = eb->batch_len;
2054 	pw->shadow = shadow;
2055 	pw->trampoline = trampoline;
2056 
2057 	/* Mark active refs early for this worker, in case we get interrupted */
2058 	err = parser_mark_active(pw, eb->context->timeline);
2059 	if (err)
2060 		goto err_commit;
2061 
2062 	err = dma_resv_lock_interruptible(pw->batch->resv, NULL);
2063 	if (err)
2064 		goto err_commit;
2065 
2066 	err = dma_resv_reserve_shared(pw->batch->resv, 1);
2067 	if (err)
2068 		goto err_commit_unlock;
2069 
2070 	/* Wait for all writes (and relocs) into the batch to complete */
2071 	err = i915_sw_fence_await_reservation(&pw->base.chain,
2072 					      pw->batch->resv, NULL, false,
2073 					      0, I915_FENCE_GFP);
2074 	if (err < 0)
2075 		goto err_commit_unlock;
2076 
2077 	/* Keep the batch alive and unwritten as we parse */
2078 	dma_resv_add_shared_fence(pw->batch->resv, &pw->base.dma);
2079 
2080 	dma_resv_unlock(pw->batch->resv);
2081 
2082 	/* Force execution to wait for completion of the parser */
2083 	dma_resv_lock(shadow->resv, NULL);
2084 	dma_resv_add_excl_fence(shadow->resv, &pw->base.dma);
2085 	dma_resv_unlock(shadow->resv);
2086 
2087 	dma_fence_work_commit_imm(&pw->base);
2088 	return 0;
2089 
2090 err_commit_unlock:
2091 	dma_resv_unlock(pw->batch->resv);
2092 err_commit:
2093 	i915_sw_fence_set_error_once(&pw->base.chain, err);
2094 	dma_fence_work_commit_imm(&pw->base);
2095 	return err;
2096 
2097 err_shadow:
2098 	i915_active_release(&shadow->active);
2099 err_batch:
2100 	i915_active_release(&eb->batch->vma->active);
2101 err_free:
2102 	kfree(pw);
2103 	return err;
2104 }
2105 
2106 static int eb_parse(struct i915_execbuffer *eb)
2107 {
2108 	struct drm_i915_private *i915 = eb->i915;
2109 	struct intel_gt_buffer_pool_node *pool;
2110 	struct i915_vma *shadow, *trampoline;
2111 	unsigned int len;
2112 	int err;
2113 
2114 	if (!eb_use_cmdparser(eb))
2115 		return 0;
2116 
2117 	len = eb->batch_len;
2118 	if (!CMDPARSER_USES_GGTT(eb->i915)) {
2119 		/*
2120 		 * ppGTT backed shadow buffers must be mapped RO, to prevent
2121 		 * post-scan tampering
2122 		 */
2123 		if (!eb->context->vm->has_read_only) {
2124 			drm_dbg(&i915->drm,
2125 				"Cannot prevent post-scan tampering without RO capable vm\n");
2126 			return -EINVAL;
2127 		}
2128 	} else {
2129 		len += I915_CMD_PARSER_TRAMPOLINE_SIZE;
2130 	}
2131 
2132 	pool = intel_gt_get_buffer_pool(eb->engine->gt, len);
2133 	if (IS_ERR(pool))
2134 		return PTR_ERR(pool);
2135 
2136 	shadow = shadow_batch_pin(pool->obj, eb->context->vm, PIN_USER);
2137 	if (IS_ERR(shadow)) {
2138 		err = PTR_ERR(shadow);
2139 		goto err;
2140 	}
2141 	i915_gem_object_set_readonly(shadow->obj);
2142 	shadow->private = pool;
2143 
2144 	trampoline = NULL;
2145 	if (CMDPARSER_USES_GGTT(eb->i915)) {
2146 		trampoline = shadow;
2147 
2148 		shadow = shadow_batch_pin(pool->obj,
2149 					  &eb->engine->gt->ggtt->vm,
2150 					  PIN_GLOBAL);
2151 		if (IS_ERR(shadow)) {
2152 			err = PTR_ERR(shadow);
2153 			shadow = trampoline;
2154 			goto err_shadow;
2155 		}
2156 		shadow->private = pool;
2157 
2158 		eb->batch_flags |= I915_DISPATCH_SECURE;
2159 	}
2160 
2161 	err = eb_parse_pipeline(eb, shadow, trampoline);
2162 	if (err)
2163 		goto err_trampoline;
2164 
2165 	eb->vma[eb->buffer_count].vma = i915_vma_get(shadow);
2166 	eb->vma[eb->buffer_count].flags = __EXEC_OBJECT_HAS_PIN;
2167 	eb->batch = &eb->vma[eb->buffer_count++];
2168 	eb->vma[eb->buffer_count].vma = NULL;
2169 
2170 	eb->trampoline = trampoline;
2171 	eb->batch_start_offset = 0;
2172 
2173 	return 0;
2174 
2175 err_trampoline:
2176 	if (trampoline)
2177 		i915_vma_unpin(trampoline);
2178 err_shadow:
2179 	i915_vma_unpin(shadow);
2180 err:
2181 	intel_gt_buffer_pool_put(pool);
2182 	return err;
2183 }
2184 
2185 static void
2186 add_to_client(struct i915_request *rq, struct drm_file *file)
2187 {
2188 	struct drm_i915_file_private *file_priv = file->driver_priv;
2189 
2190 	rq->file_priv = file_priv;
2191 
2192 	spin_lock(&file_priv->mm.lock);
2193 	list_add_tail(&rq->client_link, &file_priv->mm.request_list);
2194 	spin_unlock(&file_priv->mm.lock);
2195 }
2196 
2197 static int eb_submit(struct i915_execbuffer *eb, struct i915_vma *batch)
2198 {
2199 	int err;
2200 
2201 	err = eb_move_to_gpu(eb);
2202 	if (err)
2203 		return err;
2204 
2205 	if (eb->args->flags & I915_EXEC_GEN7_SOL_RESET) {
2206 		err = i915_reset_gen7_sol_offsets(eb->request);
2207 		if (err)
2208 			return err;
2209 	}
2210 
2211 	/*
2212 	 * After we completed waiting for other engines (using HW semaphores)
2213 	 * then we can signal that this request/batch is ready to run. This
2214 	 * allows us to determine if the batch is still waiting on the GPU
2215 	 * or actually running by checking the breadcrumb.
2216 	 */
2217 	if (eb->engine->emit_init_breadcrumb) {
2218 		err = eb->engine->emit_init_breadcrumb(eb->request);
2219 		if (err)
2220 			return err;
2221 	}
2222 
2223 	err = eb->engine->emit_bb_start(eb->request,
2224 					batch->node.start +
2225 					eb->batch_start_offset,
2226 					eb->batch_len,
2227 					eb->batch_flags);
2228 	if (err)
2229 		return err;
2230 
2231 	if (eb->trampoline) {
2232 		GEM_BUG_ON(eb->batch_start_offset);
2233 		err = eb->engine->emit_bb_start(eb->request,
2234 						eb->trampoline->node.start +
2235 						eb->batch_len,
2236 						0, 0);
2237 		if (err)
2238 			return err;
2239 	}
2240 
2241 	if (intel_context_nopreempt(eb->context))
2242 		__set_bit(I915_FENCE_FLAG_NOPREEMPT, &eb->request->fence.flags);
2243 
2244 	return 0;
2245 }
2246 
2247 static int num_vcs_engines(const struct drm_i915_private *i915)
2248 {
2249 	return hweight64(INTEL_INFO(i915)->engine_mask &
2250 			 GENMASK_ULL(VCS0 + I915_MAX_VCS - 1, VCS0));
2251 }
2252 
2253 /*
2254  * Find one BSD ring to dispatch the corresponding BSD command.
2255  * The engine index is returned.
2256  */
2257 static unsigned int
2258 gen8_dispatch_bsd_engine(struct drm_i915_private *dev_priv,
2259 			 struct drm_file *file)
2260 {
2261 	struct drm_i915_file_private *file_priv = file->driver_priv;
2262 
2263 	/* Check whether the file_priv has already selected one ring. */
2264 	if ((int)file_priv->bsd_engine < 0)
2265 		file_priv->bsd_engine =
2266 			get_random_int() % num_vcs_engines(dev_priv);
2267 
2268 	return file_priv->bsd_engine;
2269 }
2270 
2271 static const enum intel_engine_id user_ring_map[] = {
2272 	[I915_EXEC_DEFAULT]	= RCS0,
2273 	[I915_EXEC_RENDER]	= RCS0,
2274 	[I915_EXEC_BLT]		= BCS0,
2275 	[I915_EXEC_BSD]		= VCS0,
2276 	[I915_EXEC_VEBOX]	= VECS0
2277 };
2278 
2279 static struct i915_request *eb_throttle(struct intel_context *ce)
2280 {
2281 	struct intel_ring *ring = ce->ring;
2282 	struct intel_timeline *tl = ce->timeline;
2283 	struct i915_request *rq;
2284 
2285 	/*
2286 	 * Completely unscientific finger-in-the-air estimates for suitable
2287 	 * maximum user request size (to avoid blocking) and then backoff.
2288 	 */
2289 	if (intel_ring_update_space(ring) >= PAGE_SIZE)
2290 		return NULL;
2291 
2292 	/*
2293 	 * Find a request that after waiting upon, there will be at least half
2294 	 * the ring available. The hysteresis allows us to compete for the
2295 	 * shared ring and should mean that we sleep less often prior to
2296 	 * claiming our resources, but not so long that the ring completely
2297 	 * drains before we can submit our next request.
2298 	 */
2299 	list_for_each_entry(rq, &tl->requests, link) {
2300 		if (rq->ring != ring)
2301 			continue;
2302 
2303 		if (__intel_ring_space(rq->postfix,
2304 				       ring->emit, ring->size) > ring->size / 2)
2305 			break;
2306 	}
2307 	if (&rq->link == &tl->requests)
2308 		return NULL; /* weird, we will check again later for real */
2309 
2310 	return i915_request_get(rq);
2311 }
2312 
2313 static int __eb_pin_engine(struct i915_execbuffer *eb, struct intel_context *ce)
2314 {
2315 	struct intel_timeline *tl;
2316 	struct i915_request *rq;
2317 	int err;
2318 
2319 	/*
2320 	 * ABI: Before userspace accesses the GPU (e.g. execbuffer), report
2321 	 * EIO if the GPU is already wedged.
2322 	 */
2323 	err = intel_gt_terminally_wedged(ce->engine->gt);
2324 	if (err)
2325 		return err;
2326 
2327 	if (unlikely(intel_context_is_banned(ce)))
2328 		return -EIO;
2329 
2330 	/*
2331 	 * Pinning the contexts may generate requests in order to acquire
2332 	 * GGTT space, so do this first before we reserve a seqno for
2333 	 * ourselves.
2334 	 */
2335 	err = intel_context_pin(ce);
2336 	if (err)
2337 		return err;
2338 
2339 	/*
2340 	 * Take a local wakeref for preparing to dispatch the execbuf as
2341 	 * we expect to access the hardware fairly frequently in the
2342 	 * process, and require the engine to be kept awake between accesses.
2343 	 * Upon dispatch, we acquire another prolonged wakeref that we hold
2344 	 * until the timeline is idle, which in turn releases the wakeref
2345 	 * taken on the engine, and the parent device.
2346 	 */
2347 	tl = intel_context_timeline_lock(ce);
2348 	if (IS_ERR(tl)) {
2349 		err = PTR_ERR(tl);
2350 		goto err_unpin;
2351 	}
2352 
2353 	intel_context_enter(ce);
2354 	rq = eb_throttle(ce);
2355 
2356 	intel_context_timeline_unlock(tl);
2357 
2358 	if (rq) {
2359 		bool nonblock = eb->file->filp->f_flags & O_NONBLOCK;
2360 		long timeout;
2361 
2362 		timeout = MAX_SCHEDULE_TIMEOUT;
2363 		if (nonblock)
2364 			timeout = 0;
2365 
2366 		timeout = i915_request_wait(rq,
2367 					    I915_WAIT_INTERRUPTIBLE,
2368 					    timeout);
2369 		i915_request_put(rq);
2370 
2371 		if (timeout < 0) {
2372 			err = nonblock ? -EWOULDBLOCK : timeout;
2373 			goto err_exit;
2374 		}
2375 	}
2376 
2377 	eb->engine = ce->engine;
2378 	eb->context = ce;
2379 	return 0;
2380 
2381 err_exit:
2382 	mutex_lock(&tl->mutex);
2383 	intel_context_exit(ce);
2384 	intel_context_timeline_unlock(tl);
2385 err_unpin:
2386 	intel_context_unpin(ce);
2387 	return err;
2388 }
2389 
2390 static void eb_unpin_engine(struct i915_execbuffer *eb)
2391 {
2392 	struct intel_context *ce = eb->context;
2393 	struct intel_timeline *tl = ce->timeline;
2394 
2395 	mutex_lock(&tl->mutex);
2396 	intel_context_exit(ce);
2397 	mutex_unlock(&tl->mutex);
2398 
2399 	intel_context_unpin(ce);
2400 }
2401 
2402 static unsigned int
2403 eb_select_legacy_ring(struct i915_execbuffer *eb,
2404 		      struct drm_file *file,
2405 		      struct drm_i915_gem_execbuffer2 *args)
2406 {
2407 	struct drm_i915_private *i915 = eb->i915;
2408 	unsigned int user_ring_id = args->flags & I915_EXEC_RING_MASK;
2409 
2410 	if (user_ring_id != I915_EXEC_BSD &&
2411 	    (args->flags & I915_EXEC_BSD_MASK)) {
2412 		drm_dbg(&i915->drm,
2413 			"execbuf with non bsd ring but with invalid "
2414 			"bsd dispatch flags: %d\n", (int)(args->flags));
2415 		return -1;
2416 	}
2417 
2418 	if (user_ring_id == I915_EXEC_BSD && num_vcs_engines(i915) > 1) {
2419 		unsigned int bsd_idx = args->flags & I915_EXEC_BSD_MASK;
2420 
2421 		if (bsd_idx == I915_EXEC_BSD_DEFAULT) {
2422 			bsd_idx = gen8_dispatch_bsd_engine(i915, file);
2423 		} else if (bsd_idx >= I915_EXEC_BSD_RING1 &&
2424 			   bsd_idx <= I915_EXEC_BSD_RING2) {
2425 			bsd_idx >>= I915_EXEC_BSD_SHIFT;
2426 			bsd_idx--;
2427 		} else {
2428 			drm_dbg(&i915->drm,
2429 				"execbuf with unknown bsd ring: %u\n",
2430 				bsd_idx);
2431 			return -1;
2432 		}
2433 
2434 		return _VCS(bsd_idx);
2435 	}
2436 
2437 	if (user_ring_id >= ARRAY_SIZE(user_ring_map)) {
2438 		drm_dbg(&i915->drm, "execbuf with unknown ring: %u\n",
2439 			user_ring_id);
2440 		return -1;
2441 	}
2442 
2443 	return user_ring_map[user_ring_id];
2444 }
2445 
2446 static int
2447 eb_pin_engine(struct i915_execbuffer *eb,
2448 	      struct drm_file *file,
2449 	      struct drm_i915_gem_execbuffer2 *args)
2450 {
2451 	struct intel_context *ce;
2452 	unsigned int idx;
2453 	int err;
2454 
2455 	if (i915_gem_context_user_engines(eb->gem_context))
2456 		idx = args->flags & I915_EXEC_RING_MASK;
2457 	else
2458 		idx = eb_select_legacy_ring(eb, file, args);
2459 
2460 	ce = i915_gem_context_get_engine(eb->gem_context, idx);
2461 	if (IS_ERR(ce))
2462 		return PTR_ERR(ce);
2463 
2464 	err = __eb_pin_engine(eb, ce);
2465 	intel_context_put(ce);
2466 
2467 	return err;
2468 }
2469 
2470 static void
2471 __free_fence_array(struct drm_syncobj **fences, unsigned int n)
2472 {
2473 	while (n--)
2474 		drm_syncobj_put(ptr_mask_bits(fences[n], 2));
2475 	kvfree(fences);
2476 }
2477 
2478 static struct drm_syncobj **
2479 get_fence_array(struct drm_i915_gem_execbuffer2 *args,
2480 		struct drm_file *file)
2481 {
2482 	const unsigned long nfences = args->num_cliprects;
2483 	struct drm_i915_gem_exec_fence __user *user;
2484 	struct drm_syncobj **fences;
2485 	unsigned long n;
2486 	int err;
2487 
2488 	if (!(args->flags & I915_EXEC_FENCE_ARRAY))
2489 		return NULL;
2490 
2491 	/* Check multiplication overflow for access_ok() and kvmalloc_array() */
2492 	BUILD_BUG_ON(sizeof(size_t) > sizeof(unsigned long));
2493 	if (nfences > min_t(unsigned long,
2494 			    ULONG_MAX / sizeof(*user),
2495 			    SIZE_MAX / sizeof(*fences)))
2496 		return ERR_PTR(-EINVAL);
2497 
2498 	user = u64_to_user_ptr(args->cliprects_ptr);
2499 	if (!access_ok(user, nfences * sizeof(*user)))
2500 		return ERR_PTR(-EFAULT);
2501 
2502 	fences = kvmalloc_array(nfences, sizeof(*fences),
2503 				__GFP_NOWARN | GFP_KERNEL);
2504 	if (!fences)
2505 		return ERR_PTR(-ENOMEM);
2506 
2507 	for (n = 0; n < nfences; n++) {
2508 		struct drm_i915_gem_exec_fence fence;
2509 		struct drm_syncobj *syncobj;
2510 
2511 		if (__copy_from_user(&fence, user++, sizeof(fence))) {
2512 			err = -EFAULT;
2513 			goto err;
2514 		}
2515 
2516 		if (fence.flags & __I915_EXEC_FENCE_UNKNOWN_FLAGS) {
2517 			err = -EINVAL;
2518 			goto err;
2519 		}
2520 
2521 		syncobj = drm_syncobj_find(file, fence.handle);
2522 		if (!syncobj) {
2523 			DRM_DEBUG("Invalid syncobj handle provided\n");
2524 			err = -ENOENT;
2525 			goto err;
2526 		}
2527 
2528 		BUILD_BUG_ON(~(ARCH_KMALLOC_MINALIGN - 1) &
2529 			     ~__I915_EXEC_FENCE_UNKNOWN_FLAGS);
2530 
2531 		fences[n] = ptr_pack_bits(syncobj, fence.flags, 2);
2532 	}
2533 
2534 	return fences;
2535 
2536 err:
2537 	__free_fence_array(fences, n);
2538 	return ERR_PTR(err);
2539 }
2540 
2541 static void
2542 put_fence_array(struct drm_i915_gem_execbuffer2 *args,
2543 		struct drm_syncobj **fences)
2544 {
2545 	if (fences)
2546 		__free_fence_array(fences, args->num_cliprects);
2547 }
2548 
2549 static int
2550 await_fence_array(struct i915_execbuffer *eb,
2551 		  struct drm_syncobj **fences)
2552 {
2553 	const unsigned int nfences = eb->args->num_cliprects;
2554 	unsigned int n;
2555 	int err;
2556 
2557 	for (n = 0; n < nfences; n++) {
2558 		struct drm_syncobj *syncobj;
2559 		struct dma_fence *fence;
2560 		unsigned int flags;
2561 
2562 		syncobj = ptr_unpack_bits(fences[n], &flags, 2);
2563 		if (!(flags & I915_EXEC_FENCE_WAIT))
2564 			continue;
2565 
2566 		fence = drm_syncobj_fence_get(syncobj);
2567 		if (!fence)
2568 			return -EINVAL;
2569 
2570 		err = i915_request_await_dma_fence(eb->request, fence);
2571 		dma_fence_put(fence);
2572 		if (err < 0)
2573 			return err;
2574 	}
2575 
2576 	return 0;
2577 }
2578 
2579 static void
2580 signal_fence_array(struct i915_execbuffer *eb,
2581 		   struct drm_syncobj **fences)
2582 {
2583 	const unsigned int nfences = eb->args->num_cliprects;
2584 	struct dma_fence * const fence = &eb->request->fence;
2585 	unsigned int n;
2586 
2587 	for (n = 0; n < nfences; n++) {
2588 		struct drm_syncobj *syncobj;
2589 		unsigned int flags;
2590 
2591 		syncobj = ptr_unpack_bits(fences[n], &flags, 2);
2592 		if (!(flags & I915_EXEC_FENCE_SIGNAL))
2593 			continue;
2594 
2595 		drm_syncobj_replace_fence(syncobj, fence);
2596 	}
2597 }
2598 
2599 static void retire_requests(struct intel_timeline *tl, struct i915_request *end)
2600 {
2601 	struct i915_request *rq, *rn;
2602 
2603 	list_for_each_entry_safe(rq, rn, &tl->requests, link)
2604 		if (rq == end || !i915_request_retire(rq))
2605 			break;
2606 }
2607 
2608 static void eb_request_add(struct i915_execbuffer *eb)
2609 {
2610 	struct i915_request *rq = eb->request;
2611 	struct intel_timeline * const tl = i915_request_timeline(rq);
2612 	struct i915_sched_attr attr = {};
2613 	struct i915_request *prev;
2614 
2615 	lockdep_assert_held(&tl->mutex);
2616 	lockdep_unpin_lock(&tl->mutex, rq->cookie);
2617 
2618 	trace_i915_request_add(rq);
2619 
2620 	prev = __i915_request_commit(rq);
2621 
2622 	/* Check that the context wasn't destroyed before submission */
2623 	if (likely(!intel_context_is_closed(eb->context))) {
2624 		attr = eb->gem_context->sched;
2625 	} else {
2626 		/* Serialise with context_close via the add_to_timeline */
2627 		i915_request_set_error_once(rq, -ENOENT);
2628 		__i915_request_skip(rq);
2629 	}
2630 
2631 	__i915_request_queue(rq, &attr);
2632 
2633 	/* Try to clean up the client's timeline after submitting the request */
2634 	if (prev)
2635 		retire_requests(tl, prev);
2636 
2637 	mutex_unlock(&tl->mutex);
2638 }
2639 
2640 static int
2641 i915_gem_do_execbuffer(struct drm_device *dev,
2642 		       struct drm_file *file,
2643 		       struct drm_i915_gem_execbuffer2 *args,
2644 		       struct drm_i915_gem_exec_object2 *exec,
2645 		       struct drm_syncobj **fences)
2646 {
2647 	struct drm_i915_private *i915 = to_i915(dev);
2648 	struct i915_execbuffer eb;
2649 	struct dma_fence *in_fence = NULL;
2650 	struct sync_file *out_fence = NULL;
2651 	struct i915_vma *batch;
2652 	int out_fence_fd = -1;
2653 	int err;
2654 
2655 	BUILD_BUG_ON(__EXEC_INTERNAL_FLAGS & ~__I915_EXEC_ILLEGAL_FLAGS);
2656 	BUILD_BUG_ON(__EXEC_OBJECT_INTERNAL_FLAGS &
2657 		     ~__EXEC_OBJECT_UNKNOWN_FLAGS);
2658 
2659 	eb.i915 = i915;
2660 	eb.file = file;
2661 	eb.args = args;
2662 	if (DBG_FORCE_RELOC || !(args->flags & I915_EXEC_NO_RELOC))
2663 		args->flags |= __EXEC_HAS_RELOC;
2664 
2665 	eb.exec = exec;
2666 
2667 	eb.invalid_flags = __EXEC_OBJECT_UNKNOWN_FLAGS;
2668 	reloc_cache_init(&eb.reloc_cache, eb.i915);
2669 
2670 	eb.buffer_count = args->buffer_count;
2671 	eb.batch_start_offset = args->batch_start_offset;
2672 	eb.batch_len = args->batch_len;
2673 	eb.trampoline = NULL;
2674 
2675 	eb.batch_flags = 0;
2676 	if (args->flags & I915_EXEC_SECURE) {
2677 		if (INTEL_GEN(i915) >= 11)
2678 			return -ENODEV;
2679 
2680 		/* Return -EPERM to trigger fallback code on old binaries. */
2681 		if (!HAS_SECURE_BATCHES(i915))
2682 			return -EPERM;
2683 
2684 		if (!drm_is_current_master(file) || !capable(CAP_SYS_ADMIN))
2685 			return -EPERM;
2686 
2687 		eb.batch_flags |= I915_DISPATCH_SECURE;
2688 	}
2689 	if (args->flags & I915_EXEC_IS_PINNED)
2690 		eb.batch_flags |= I915_DISPATCH_PINNED;
2691 
2692 #define IN_FENCES (I915_EXEC_FENCE_IN | I915_EXEC_FENCE_SUBMIT)
2693 	if (args->flags & IN_FENCES) {
2694 		if ((args->flags & IN_FENCES) == IN_FENCES)
2695 			return -EINVAL;
2696 
2697 		in_fence = sync_file_get_fence(lower_32_bits(args->rsvd2));
2698 		if (!in_fence)
2699 			return -EINVAL;
2700 	}
2701 #undef IN_FENCES
2702 
2703 	if (args->flags & I915_EXEC_FENCE_OUT) {
2704 		out_fence_fd = get_unused_fd_flags(O_CLOEXEC);
2705 		if (out_fence_fd < 0) {
2706 			err = out_fence_fd;
2707 			goto err_in_fence;
2708 		}
2709 	}
2710 
2711 	err = eb_create(&eb);
2712 	if (err)
2713 		goto err_out_fence;
2714 
2715 	GEM_BUG_ON(!eb.lut_size);
2716 
2717 	err = eb_select_context(&eb);
2718 	if (unlikely(err))
2719 		goto err_destroy;
2720 
2721 	err = eb_pin_engine(&eb, file, args);
2722 	if (unlikely(err))
2723 		goto err_context;
2724 
2725 	err = eb_relocate(&eb);
2726 	if (err) {
2727 		/*
2728 		 * If the user expects the execobject.offset and
2729 		 * reloc.presumed_offset to be an exact match,
2730 		 * as for using NO_RELOC, then we cannot update
2731 		 * the execobject.offset until we have completed
2732 		 * relocation.
2733 		 */
2734 		args->flags &= ~__EXEC_HAS_RELOC;
2735 		goto err_vma;
2736 	}
2737 
2738 	if (unlikely(eb.batch->flags & EXEC_OBJECT_WRITE)) {
2739 		drm_dbg(&i915->drm,
2740 			"Attempting to use self-modifying batch buffer\n");
2741 		err = -EINVAL;
2742 		goto err_vma;
2743 	}
2744 
2745 	if (range_overflows_t(u64,
2746 			      eb.batch_start_offset, eb.batch_len,
2747 			      eb.batch->vma->size)) {
2748 		drm_dbg(&i915->drm, "Attempting to use out-of-bounds batch\n");
2749 		err = -EINVAL;
2750 		goto err_vma;
2751 	}
2752 
2753 	if (eb.batch_len == 0)
2754 		eb.batch_len = eb.batch->vma->size - eb.batch_start_offset;
2755 
2756 	err = eb_parse(&eb);
2757 	if (err)
2758 		goto err_vma;
2759 
2760 	/*
2761 	 * snb/ivb/vlv conflate the "batch in ppgtt" bit with the "non-secure
2762 	 * batch" bit. Hence we need to pin secure batches into the global gtt.
2763 	 * hsw should have this fixed, but bdw mucks it up again. */
2764 	batch = eb.batch->vma;
2765 	if (eb.batch_flags & I915_DISPATCH_SECURE) {
2766 		struct i915_vma *vma;
2767 
2768 		/*
2769 		 * So on first glance it looks freaky that we pin the batch here
2770 		 * outside of the reservation loop. But:
2771 		 * - The batch is already pinned into the relevant ppgtt, so we
2772 		 *   already have the backing storage fully allocated.
2773 		 * - No other BO uses the global gtt (well contexts, but meh),
2774 		 *   so we don't really have issues with multiple objects not
2775 		 *   fitting due to fragmentation.
2776 		 * So this is actually safe.
2777 		 */
2778 		vma = i915_gem_object_ggtt_pin(batch->obj, NULL, 0, 0, 0);
2779 		if (IS_ERR(vma)) {
2780 			err = PTR_ERR(vma);
2781 			goto err_parse;
2782 		}
2783 
2784 		batch = vma;
2785 	}
2786 
2787 	/* All GPU relocation batches must be submitted prior to the user rq */
2788 	GEM_BUG_ON(eb.reloc_cache.rq);
2789 
2790 	/* Allocate a request for this batch buffer nice and early. */
2791 	eb.request = i915_request_create(eb.context);
2792 	if (IS_ERR(eb.request)) {
2793 		err = PTR_ERR(eb.request);
2794 		goto err_batch_unpin;
2795 	}
2796 
2797 	if (in_fence) {
2798 		if (args->flags & I915_EXEC_FENCE_SUBMIT)
2799 			err = i915_request_await_execution(eb.request,
2800 							   in_fence,
2801 							   eb.engine->bond_execute);
2802 		else
2803 			err = i915_request_await_dma_fence(eb.request,
2804 							   in_fence);
2805 		if (err < 0)
2806 			goto err_request;
2807 	}
2808 
2809 	if (fences) {
2810 		err = await_fence_array(&eb, fences);
2811 		if (err)
2812 			goto err_request;
2813 	}
2814 
2815 	if (out_fence_fd != -1) {
2816 		out_fence = sync_file_create(&eb.request->fence);
2817 		if (!out_fence) {
2818 			err = -ENOMEM;
2819 			goto err_request;
2820 		}
2821 	}
2822 
2823 	/*
2824 	 * Whilst this request exists, batch_obj will be on the
2825 	 * active_list, and so will hold the active reference. Only when this
2826 	 * request is retired will the the batch_obj be moved onto the
2827 	 * inactive_list and lose its active reference. Hence we do not need
2828 	 * to explicitly hold another reference here.
2829 	 */
2830 	eb.request->batch = batch;
2831 	if (batch->private)
2832 		intel_gt_buffer_pool_mark_active(batch->private, eb.request);
2833 
2834 	trace_i915_request_queue(eb.request, eb.batch_flags);
2835 	err = eb_submit(&eb, batch);
2836 err_request:
2837 	add_to_client(eb.request, file);
2838 	i915_request_get(eb.request);
2839 	eb_request_add(&eb);
2840 
2841 	if (fences)
2842 		signal_fence_array(&eb, fences);
2843 
2844 	if (out_fence) {
2845 		if (err == 0) {
2846 			fd_install(out_fence_fd, out_fence->file);
2847 			args->rsvd2 &= GENMASK_ULL(31, 0); /* keep in-fence */
2848 			args->rsvd2 |= (u64)out_fence_fd << 32;
2849 			out_fence_fd = -1;
2850 		} else {
2851 			fput(out_fence->file);
2852 		}
2853 	}
2854 	i915_request_put(eb.request);
2855 
2856 err_batch_unpin:
2857 	if (eb.batch_flags & I915_DISPATCH_SECURE)
2858 		i915_vma_unpin(batch);
2859 err_parse:
2860 	if (batch->private)
2861 		intel_gt_buffer_pool_put(batch->private);
2862 err_vma:
2863 	if (eb.trampoline)
2864 		i915_vma_unpin(eb.trampoline);
2865 	eb_unpin_engine(&eb);
2866 err_context:
2867 	i915_gem_context_put(eb.gem_context);
2868 err_destroy:
2869 	eb_destroy(&eb);
2870 err_out_fence:
2871 	if (out_fence_fd != -1)
2872 		put_unused_fd(out_fence_fd);
2873 err_in_fence:
2874 	dma_fence_put(in_fence);
2875 	return err;
2876 }
2877 
2878 static size_t eb_element_size(void)
2879 {
2880 	return sizeof(struct drm_i915_gem_exec_object2);
2881 }
2882 
2883 static bool check_buffer_count(size_t count)
2884 {
2885 	const size_t sz = eb_element_size();
2886 
2887 	/*
2888 	 * When using LUT_HANDLE, we impose a limit of INT_MAX for the lookup
2889 	 * array size (see eb_create()). Otherwise, we can accept an array as
2890 	 * large as can be addressed (though use large arrays at your peril)!
2891 	 */
2892 
2893 	return !(count < 1 || count > INT_MAX || count > SIZE_MAX / sz - 1);
2894 }
2895 
2896 /*
2897  * Legacy execbuffer just creates an exec2 list from the original exec object
2898  * list array and passes it to the real function.
2899  */
2900 int
2901 i915_gem_execbuffer_ioctl(struct drm_device *dev, void *data,
2902 			  struct drm_file *file)
2903 {
2904 	struct drm_i915_private *i915 = to_i915(dev);
2905 	struct drm_i915_gem_execbuffer *args = data;
2906 	struct drm_i915_gem_execbuffer2 exec2;
2907 	struct drm_i915_gem_exec_object *exec_list = NULL;
2908 	struct drm_i915_gem_exec_object2 *exec2_list = NULL;
2909 	const size_t count = args->buffer_count;
2910 	unsigned int i;
2911 	int err;
2912 
2913 	if (!check_buffer_count(count)) {
2914 		drm_dbg(&i915->drm, "execbuf2 with %zd buffers\n", count);
2915 		return -EINVAL;
2916 	}
2917 
2918 	exec2.buffers_ptr = args->buffers_ptr;
2919 	exec2.buffer_count = args->buffer_count;
2920 	exec2.batch_start_offset = args->batch_start_offset;
2921 	exec2.batch_len = args->batch_len;
2922 	exec2.DR1 = args->DR1;
2923 	exec2.DR4 = args->DR4;
2924 	exec2.num_cliprects = args->num_cliprects;
2925 	exec2.cliprects_ptr = args->cliprects_ptr;
2926 	exec2.flags = I915_EXEC_RENDER;
2927 	i915_execbuffer2_set_context_id(exec2, 0);
2928 
2929 	err = i915_gem_check_execbuffer(&exec2);
2930 	if (err)
2931 		return err;
2932 
2933 	/* Copy in the exec list from userland */
2934 	exec_list = kvmalloc_array(count, sizeof(*exec_list),
2935 				   __GFP_NOWARN | GFP_KERNEL);
2936 	exec2_list = kvmalloc_array(count, eb_element_size(),
2937 				    __GFP_NOWARN | GFP_KERNEL);
2938 	if (exec_list == NULL || exec2_list == NULL) {
2939 		drm_dbg(&i915->drm,
2940 			"Failed to allocate exec list for %d buffers\n",
2941 			args->buffer_count);
2942 		kvfree(exec_list);
2943 		kvfree(exec2_list);
2944 		return -ENOMEM;
2945 	}
2946 	err = copy_from_user(exec_list,
2947 			     u64_to_user_ptr(args->buffers_ptr),
2948 			     sizeof(*exec_list) * count);
2949 	if (err) {
2950 		drm_dbg(&i915->drm, "copy %d exec entries failed %d\n",
2951 			args->buffer_count, err);
2952 		kvfree(exec_list);
2953 		kvfree(exec2_list);
2954 		return -EFAULT;
2955 	}
2956 
2957 	for (i = 0; i < args->buffer_count; i++) {
2958 		exec2_list[i].handle = exec_list[i].handle;
2959 		exec2_list[i].relocation_count = exec_list[i].relocation_count;
2960 		exec2_list[i].relocs_ptr = exec_list[i].relocs_ptr;
2961 		exec2_list[i].alignment = exec_list[i].alignment;
2962 		exec2_list[i].offset = exec_list[i].offset;
2963 		if (INTEL_GEN(to_i915(dev)) < 4)
2964 			exec2_list[i].flags = EXEC_OBJECT_NEEDS_FENCE;
2965 		else
2966 			exec2_list[i].flags = 0;
2967 	}
2968 
2969 	err = i915_gem_do_execbuffer(dev, file, &exec2, exec2_list, NULL);
2970 	if (exec2.flags & __EXEC_HAS_RELOC) {
2971 		struct drm_i915_gem_exec_object __user *user_exec_list =
2972 			u64_to_user_ptr(args->buffers_ptr);
2973 
2974 		/* Copy the new buffer offsets back to the user's exec list. */
2975 		for (i = 0; i < args->buffer_count; i++) {
2976 			if (!(exec2_list[i].offset & UPDATE))
2977 				continue;
2978 
2979 			exec2_list[i].offset =
2980 				gen8_canonical_addr(exec2_list[i].offset & PIN_OFFSET_MASK);
2981 			exec2_list[i].offset &= PIN_OFFSET_MASK;
2982 			if (__copy_to_user(&user_exec_list[i].offset,
2983 					   &exec2_list[i].offset,
2984 					   sizeof(user_exec_list[i].offset)))
2985 				break;
2986 		}
2987 	}
2988 
2989 	kvfree(exec_list);
2990 	kvfree(exec2_list);
2991 	return err;
2992 }
2993 
2994 int
2995 i915_gem_execbuffer2_ioctl(struct drm_device *dev, void *data,
2996 			   struct drm_file *file)
2997 {
2998 	struct drm_i915_private *i915 = to_i915(dev);
2999 	struct drm_i915_gem_execbuffer2 *args = data;
3000 	struct drm_i915_gem_exec_object2 *exec2_list;
3001 	struct drm_syncobj **fences = NULL;
3002 	const size_t count = args->buffer_count;
3003 	int err;
3004 
3005 	if (!check_buffer_count(count)) {
3006 		drm_dbg(&i915->drm, "execbuf2 with %zd buffers\n", count);
3007 		return -EINVAL;
3008 	}
3009 
3010 	err = i915_gem_check_execbuffer(args);
3011 	if (err)
3012 		return err;
3013 
3014 	exec2_list = kvmalloc_array(count, eb_element_size(),
3015 				    __GFP_NOWARN | GFP_KERNEL);
3016 	if (exec2_list == NULL) {
3017 		drm_dbg(&i915->drm, "Failed to allocate exec list for %zd buffers\n",
3018 			count);
3019 		return -ENOMEM;
3020 	}
3021 	if (copy_from_user(exec2_list,
3022 			   u64_to_user_ptr(args->buffers_ptr),
3023 			   sizeof(*exec2_list) * count)) {
3024 		drm_dbg(&i915->drm, "copy %zd exec entries failed\n", count);
3025 		kvfree(exec2_list);
3026 		return -EFAULT;
3027 	}
3028 
3029 	if (args->flags & I915_EXEC_FENCE_ARRAY) {
3030 		fences = get_fence_array(args, file);
3031 		if (IS_ERR(fences)) {
3032 			kvfree(exec2_list);
3033 			return PTR_ERR(fences);
3034 		}
3035 	}
3036 
3037 	err = i915_gem_do_execbuffer(dev, file, args, exec2_list, fences);
3038 
3039 	/*
3040 	 * Now that we have begun execution of the batchbuffer, we ignore
3041 	 * any new error after this point. Also given that we have already
3042 	 * updated the associated relocations, we try to write out the current
3043 	 * object locations irrespective of any error.
3044 	 */
3045 	if (args->flags & __EXEC_HAS_RELOC) {
3046 		struct drm_i915_gem_exec_object2 __user *user_exec_list =
3047 			u64_to_user_ptr(args->buffers_ptr);
3048 		unsigned int i;
3049 
3050 		/* Copy the new buffer offsets back to the user's exec list. */
3051 		/*
3052 		 * Note: count * sizeof(*user_exec_list) does not overflow,
3053 		 * because we checked 'count' in check_buffer_count().
3054 		 *
3055 		 * And this range already got effectively checked earlier
3056 		 * when we did the "copy_from_user()" above.
3057 		 */
3058 		if (!user_write_access_begin(user_exec_list,
3059 					     count * sizeof(*user_exec_list)))
3060 			goto end;
3061 
3062 		for (i = 0; i < args->buffer_count; i++) {
3063 			if (!(exec2_list[i].offset & UPDATE))
3064 				continue;
3065 
3066 			exec2_list[i].offset =
3067 				gen8_canonical_addr(exec2_list[i].offset & PIN_OFFSET_MASK);
3068 			unsafe_put_user(exec2_list[i].offset,
3069 					&user_exec_list[i].offset,
3070 					end_user);
3071 		}
3072 end_user:
3073 		user_write_access_end();
3074 end:;
3075 	}
3076 
3077 	args->flags &= ~__I915_EXEC_UNKNOWN_FLAGS;
3078 	put_fence_array(args, fences);
3079 	kvfree(exec2_list);
3080 	return err;
3081 }
3082 
3083 #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
3084 #include "selftests/i915_gem_execbuffer.c"
3085 #endif
3086