1 /*
2  * Copyright (C) 2013 Red Hat
3  * Author: Rob Clark <robdclark@gmail.com>
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms of the GNU General Public License version 2 as published by
7  * the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12  * more details.
13  *
14  * You should have received a copy of the GNU General Public License along with
15  * this program.  If not, see <http://www.gnu.org/licenses/>.
16  */
17 
18 #include <linux/sync_file.h>
19 
20 #include "msm_drv.h"
21 #include "msm_gpu.h"
22 #include "msm_gem.h"
23 
24 /*
25  * Cmdstream submission:
26  */
27 
28 /* make sure these don't conflict w/ MSM_SUBMIT_BO_x */
29 #define BO_VALID    0x8000   /* is current addr in cmdstream correct/valid? */
30 #define BO_LOCKED   0x4000
31 #define BO_PINNED   0x2000
32 
33 static struct msm_gem_submit *submit_create(struct drm_device *dev,
34 		struct msm_gpu *gpu, int nr_bos, int nr_cmds)
35 {
36 	struct msm_gem_submit *submit;
37 	int sz = sizeof(*submit) + (nr_bos * sizeof(submit->bos[0])) +
38 			(nr_cmds * sizeof(*submit->cmd));
39 
40 	submit = kmalloc(sz, GFP_TEMPORARY | __GFP_NOWARN | __GFP_NORETRY);
41 	if (!submit)
42 		return NULL;
43 
44 	submit->dev = dev;
45 	submit->gpu = gpu;
46 	submit->fence = NULL;
47 	submit->pid = get_pid(task_pid(current));
48 	submit->cmd = (void *)&submit->bos[nr_bos];
49 
50 	/* initially, until copy_from_user() and bo lookup succeeds: */
51 	submit->nr_bos = 0;
52 	submit->nr_cmds = 0;
53 
54 	INIT_LIST_HEAD(&submit->node);
55 	INIT_LIST_HEAD(&submit->bo_list);
56 	ww_acquire_init(&submit->ticket, &reservation_ww_class);
57 
58 	return submit;
59 }
60 
61 void msm_gem_submit_free(struct msm_gem_submit *submit)
62 {
63 	fence_put(submit->fence);
64 	list_del(&submit->node);
65 	put_pid(submit->pid);
66 	kfree(submit);
67 }
68 
69 static inline unsigned long __must_check
70 copy_from_user_inatomic(void *to, const void __user *from, unsigned long n)
71 {
72 	if (access_ok(VERIFY_READ, from, n))
73 		return __copy_from_user_inatomic(to, from, n);
74 	return -EFAULT;
75 }
76 
77 static int submit_lookup_objects(struct msm_gem_submit *submit,
78 		struct drm_msm_gem_submit *args, struct drm_file *file)
79 {
80 	unsigned i;
81 	int ret = 0;
82 
83 	spin_lock(&file->table_lock);
84 	pagefault_disable();
85 
86 	for (i = 0; i < args->nr_bos; i++) {
87 		struct drm_msm_gem_submit_bo submit_bo;
88 		struct drm_gem_object *obj;
89 		struct msm_gem_object *msm_obj;
90 		void __user *userptr =
91 			u64_to_user_ptr(args->bos + (i * sizeof(submit_bo)));
92 
93 		/* make sure we don't have garbage flags, in case we hit
94 		 * error path before flags is initialized:
95 		 */
96 		submit->bos[i].flags = 0;
97 
98 		ret = copy_from_user_inatomic(&submit_bo, userptr, sizeof(submit_bo));
99 		if (unlikely(ret)) {
100 			pagefault_enable();
101 			spin_unlock(&file->table_lock);
102 			ret = copy_from_user(&submit_bo, userptr, sizeof(submit_bo));
103 			if (ret)
104 				goto out;
105 			spin_lock(&file->table_lock);
106 			pagefault_disable();
107 		}
108 
109 		if (submit_bo.flags & ~MSM_SUBMIT_BO_FLAGS) {
110 			DRM_ERROR("invalid flags: %x\n", submit_bo.flags);
111 			ret = -EINVAL;
112 			goto out_unlock;
113 		}
114 
115 		submit->bos[i].flags = submit_bo.flags;
116 		/* in validate_objects() we figure out if this is true: */
117 		submit->bos[i].iova  = submit_bo.presumed;
118 
119 		/* normally use drm_gem_object_lookup(), but for bulk lookup
120 		 * all under single table_lock just hit object_idr directly:
121 		 */
122 		obj = idr_find(&file->object_idr, submit_bo.handle);
123 		if (!obj) {
124 			DRM_ERROR("invalid handle %u at index %u\n", submit_bo.handle, i);
125 			ret = -EINVAL;
126 			goto out_unlock;
127 		}
128 
129 		msm_obj = to_msm_bo(obj);
130 
131 		if (!list_empty(&msm_obj->submit_entry)) {
132 			DRM_ERROR("handle %u at index %u already on submit list\n",
133 					submit_bo.handle, i);
134 			ret = -EINVAL;
135 			goto out_unlock;
136 		}
137 
138 		drm_gem_object_reference(obj);
139 
140 		submit->bos[i].obj = msm_obj;
141 
142 		list_add_tail(&msm_obj->submit_entry, &submit->bo_list);
143 	}
144 
145 out_unlock:
146 	pagefault_enable();
147 	spin_unlock(&file->table_lock);
148 
149 out:
150 	submit->nr_bos = i;
151 
152 	return ret;
153 }
154 
155 static void submit_unlock_unpin_bo(struct msm_gem_submit *submit, int i)
156 {
157 	struct msm_gem_object *msm_obj = submit->bos[i].obj;
158 
159 	if (submit->bos[i].flags & BO_PINNED)
160 		msm_gem_put_iova(&msm_obj->base, submit->gpu->id);
161 
162 	if (submit->bos[i].flags & BO_LOCKED)
163 		ww_mutex_unlock(&msm_obj->resv->lock);
164 
165 	if (!(submit->bos[i].flags & BO_VALID))
166 		submit->bos[i].iova = 0;
167 
168 	submit->bos[i].flags &= ~(BO_LOCKED | BO_PINNED);
169 }
170 
171 /* This is where we make sure all the bo's are reserved and pin'd: */
172 static int submit_lock_objects(struct msm_gem_submit *submit)
173 {
174 	int contended, slow_locked = -1, i, ret = 0;
175 
176 retry:
177 	for (i = 0; i < submit->nr_bos; i++) {
178 		struct msm_gem_object *msm_obj = submit->bos[i].obj;
179 
180 		if (slow_locked == i)
181 			slow_locked = -1;
182 
183 		contended = i;
184 
185 		if (!(submit->bos[i].flags & BO_LOCKED)) {
186 			ret = ww_mutex_lock_interruptible(&msm_obj->resv->lock,
187 					&submit->ticket);
188 			if (ret)
189 				goto fail;
190 			submit->bos[i].flags |= BO_LOCKED;
191 		}
192 	}
193 
194 	ww_acquire_done(&submit->ticket);
195 
196 	return 0;
197 
198 fail:
199 	for (; i >= 0; i--)
200 		submit_unlock_unpin_bo(submit, i);
201 
202 	if (slow_locked > 0)
203 		submit_unlock_unpin_bo(submit, slow_locked);
204 
205 	if (ret == -EDEADLK) {
206 		struct msm_gem_object *msm_obj = submit->bos[contended].obj;
207 		/* we lost out in a seqno race, lock and retry.. */
208 		ret = ww_mutex_lock_slow_interruptible(&msm_obj->resv->lock,
209 				&submit->ticket);
210 		if (!ret) {
211 			submit->bos[contended].flags |= BO_LOCKED;
212 			slow_locked = contended;
213 			goto retry;
214 		}
215 	}
216 
217 	return ret;
218 }
219 
220 static int submit_fence_sync(struct msm_gem_submit *submit)
221 {
222 	int i, ret = 0;
223 
224 	for (i = 0; i < submit->nr_bos; i++) {
225 		struct msm_gem_object *msm_obj = submit->bos[i].obj;
226 		bool write = submit->bos[i].flags & MSM_SUBMIT_BO_WRITE;
227 
228 		ret = msm_gem_sync_object(&msm_obj->base, submit->gpu->fctx, write);
229 		if (ret)
230 			break;
231 	}
232 
233 	return ret;
234 }
235 
236 static int submit_pin_objects(struct msm_gem_submit *submit)
237 {
238 	int i, ret = 0;
239 
240 	submit->valid = true;
241 
242 	for (i = 0; i < submit->nr_bos; i++) {
243 		struct msm_gem_object *msm_obj = submit->bos[i].obj;
244 		uint32_t iova;
245 
246 		/* if locking succeeded, pin bo: */
247 		ret = msm_gem_get_iova_locked(&msm_obj->base,
248 				submit->gpu->id, &iova);
249 
250 		if (ret)
251 			break;
252 
253 		submit->bos[i].flags |= BO_PINNED;
254 
255 		if (iova == submit->bos[i].iova) {
256 			submit->bos[i].flags |= BO_VALID;
257 		} else {
258 			submit->bos[i].iova = iova;
259 			/* iova changed, so address in cmdstream is not valid: */
260 			submit->bos[i].flags &= ~BO_VALID;
261 			submit->valid = false;
262 		}
263 	}
264 
265 	return ret;
266 }
267 
268 static int submit_bo(struct msm_gem_submit *submit, uint32_t idx,
269 		struct msm_gem_object **obj, uint32_t *iova, bool *valid)
270 {
271 	if (idx >= submit->nr_bos) {
272 		DRM_ERROR("invalid buffer index: %u (out of %u)\n",
273 				idx, submit->nr_bos);
274 		return -EINVAL;
275 	}
276 
277 	if (obj)
278 		*obj = submit->bos[idx].obj;
279 	if (iova)
280 		*iova = submit->bos[idx].iova;
281 	if (valid)
282 		*valid = !!(submit->bos[idx].flags & BO_VALID);
283 
284 	return 0;
285 }
286 
287 /* process the reloc's and patch up the cmdstream as needed: */
288 static int submit_reloc(struct msm_gem_submit *submit, struct msm_gem_object *obj,
289 		uint32_t offset, uint32_t nr_relocs, uint64_t relocs)
290 {
291 	uint32_t i, last_offset = 0;
292 	uint32_t *ptr;
293 	int ret;
294 
295 	if (offset % 4) {
296 		DRM_ERROR("non-aligned cmdstream buffer: %u\n", offset);
297 		return -EINVAL;
298 	}
299 
300 	/* For now, just map the entire thing.  Eventually we probably
301 	 * to do it page-by-page, w/ kmap() if not vmap()d..
302 	 */
303 	ptr = msm_gem_get_vaddr_locked(&obj->base);
304 
305 	if (IS_ERR(ptr)) {
306 		ret = PTR_ERR(ptr);
307 		DBG("failed to map: %d", ret);
308 		return ret;
309 	}
310 
311 	for (i = 0; i < nr_relocs; i++) {
312 		struct drm_msm_gem_submit_reloc submit_reloc;
313 		void __user *userptr =
314 			u64_to_user_ptr(relocs + (i * sizeof(submit_reloc)));
315 		uint32_t iova, off;
316 		bool valid;
317 
318 		ret = copy_from_user(&submit_reloc, userptr, sizeof(submit_reloc));
319 		if (ret)
320 			return -EFAULT;
321 
322 		if (submit_reloc.submit_offset % 4) {
323 			DRM_ERROR("non-aligned reloc offset: %u\n",
324 					submit_reloc.submit_offset);
325 			return -EINVAL;
326 		}
327 
328 		/* offset in dwords: */
329 		off = submit_reloc.submit_offset / 4;
330 
331 		if ((off >= (obj->base.size / 4)) ||
332 				(off < last_offset)) {
333 			DRM_ERROR("invalid offset %u at reloc %u\n", off, i);
334 			return -EINVAL;
335 		}
336 
337 		ret = submit_bo(submit, submit_reloc.reloc_idx, NULL, &iova, &valid);
338 		if (ret)
339 			return ret;
340 
341 		if (valid)
342 			continue;
343 
344 		iova += submit_reloc.reloc_offset;
345 
346 		if (submit_reloc.shift < 0)
347 			iova >>= -submit_reloc.shift;
348 		else
349 			iova <<= submit_reloc.shift;
350 
351 		ptr[off] = iova | submit_reloc.or;
352 
353 		last_offset = off;
354 	}
355 
356 	msm_gem_put_vaddr_locked(&obj->base);
357 
358 	return 0;
359 }
360 
361 static void submit_cleanup(struct msm_gem_submit *submit)
362 {
363 	unsigned i;
364 
365 	for (i = 0; i < submit->nr_bos; i++) {
366 		struct msm_gem_object *msm_obj = submit->bos[i].obj;
367 		submit_unlock_unpin_bo(submit, i);
368 		list_del_init(&msm_obj->submit_entry);
369 		drm_gem_object_unreference(&msm_obj->base);
370 	}
371 
372 	ww_acquire_fini(&submit->ticket);
373 }
374 
375 int msm_ioctl_gem_submit(struct drm_device *dev, void *data,
376 		struct drm_file *file)
377 {
378 	struct msm_drm_private *priv = dev->dev_private;
379 	struct drm_msm_gem_submit *args = data;
380 	struct msm_file_private *ctx = file->driver_priv;
381 	struct msm_gem_submit *submit;
382 	struct msm_gpu *gpu = priv->gpu;
383 	struct fence *in_fence = NULL;
384 	struct sync_file *sync_file = NULL;
385 	int out_fence_fd = -1;
386 	unsigned i;
387 	int ret;
388 
389 	if (!gpu)
390 		return -ENXIO;
391 
392 	/* for now, we just have 3d pipe.. eventually this would need to
393 	 * be more clever to dispatch to appropriate gpu module:
394 	 */
395 	if (MSM_PIPE_ID(args->flags) != MSM_PIPE_3D0)
396 		return -EINVAL;
397 
398 	if (MSM_PIPE_FLAGS(args->flags) & ~MSM_SUBMIT_FLAGS)
399 		return -EINVAL;
400 
401 	ret = mutex_lock_interruptible(&dev->struct_mutex);
402 	if (ret)
403 		return ret;
404 
405 	if (args->flags & MSM_SUBMIT_FENCE_FD_OUT) {
406 		out_fence_fd = get_unused_fd_flags(O_CLOEXEC);
407 		if (out_fence_fd < 0) {
408 			ret = out_fence_fd;
409 			goto out_unlock;
410 		}
411 	}
412 	priv->struct_mutex_task = current;
413 
414 	submit = submit_create(dev, gpu, args->nr_bos, args->nr_cmds);
415 	if (!submit) {
416 		ret = -ENOMEM;
417 		goto out_unlock;
418 	}
419 
420 	ret = submit_lookup_objects(submit, args, file);
421 	if (ret)
422 		goto out;
423 
424 	ret = submit_lock_objects(submit);
425 	if (ret)
426 		goto out;
427 
428 	if (args->flags & MSM_SUBMIT_FENCE_FD_IN) {
429 		in_fence = sync_file_get_fence(args->fence_fd);
430 
431 		if (!in_fence) {
432 			ret = -EINVAL;
433 			goto out;
434 		}
435 
436 		/* TODO if we get an array-fence due to userspace merging multiple
437 		 * fences, we need a way to determine if all the backing fences
438 		 * are from our own context..
439 		 */
440 
441 		if (in_fence->context != gpu->fctx->context) {
442 			ret = fence_wait(in_fence, true);
443 			if (ret)
444 				goto out;
445 		}
446 
447 	}
448 
449 	if (!(args->fence & MSM_SUBMIT_NO_IMPLICIT)) {
450 		ret = submit_fence_sync(submit);
451 		if (ret)
452 			goto out;
453 	}
454 
455 	ret = submit_pin_objects(submit);
456 	if (ret)
457 		goto out;
458 
459 	for (i = 0; i < args->nr_cmds; i++) {
460 		struct drm_msm_gem_submit_cmd submit_cmd;
461 		void __user *userptr =
462 			u64_to_user_ptr(args->cmds + (i * sizeof(submit_cmd)));
463 		struct msm_gem_object *msm_obj;
464 		uint32_t iova;
465 
466 		ret = copy_from_user(&submit_cmd, userptr, sizeof(submit_cmd));
467 		if (ret) {
468 			ret = -EFAULT;
469 			goto out;
470 		}
471 
472 		/* validate input from userspace: */
473 		switch (submit_cmd.type) {
474 		case MSM_SUBMIT_CMD_BUF:
475 		case MSM_SUBMIT_CMD_IB_TARGET_BUF:
476 		case MSM_SUBMIT_CMD_CTX_RESTORE_BUF:
477 			break;
478 		default:
479 			DRM_ERROR("invalid type: %08x\n", submit_cmd.type);
480 			ret = -EINVAL;
481 			goto out;
482 		}
483 
484 		ret = submit_bo(submit, submit_cmd.submit_idx,
485 				&msm_obj, &iova, NULL);
486 		if (ret)
487 			goto out;
488 
489 		if (submit_cmd.size % 4) {
490 			DRM_ERROR("non-aligned cmdstream buffer size: %u\n",
491 					submit_cmd.size);
492 			ret = -EINVAL;
493 			goto out;
494 		}
495 
496 		if ((submit_cmd.size + submit_cmd.submit_offset) >=
497 				msm_obj->base.size) {
498 			DRM_ERROR("invalid cmdstream size: %u\n", submit_cmd.size);
499 			ret = -EINVAL;
500 			goto out;
501 		}
502 
503 		submit->cmd[i].type = submit_cmd.type;
504 		submit->cmd[i].size = submit_cmd.size / 4;
505 		submit->cmd[i].iova = iova + submit_cmd.submit_offset;
506 		submit->cmd[i].idx  = submit_cmd.submit_idx;
507 
508 		if (submit->valid)
509 			continue;
510 
511 		ret = submit_reloc(submit, msm_obj, submit_cmd.submit_offset,
512 				submit_cmd.nr_relocs, submit_cmd.relocs);
513 		if (ret)
514 			goto out;
515 	}
516 
517 	submit->nr_cmds = i;
518 
519 	submit->fence = msm_fence_alloc(gpu->fctx);
520 	if (IS_ERR(submit->fence)) {
521 		ret = PTR_ERR(submit->fence);
522 		submit->fence = NULL;
523 		goto out;
524 	}
525 
526 	if (args->flags & MSM_SUBMIT_FENCE_FD_OUT) {
527 		sync_file = sync_file_create(submit->fence);
528 		if (!sync_file) {
529 			ret = -ENOMEM;
530 			goto out;
531 		}
532 	}
533 
534 	msm_gpu_submit(gpu, submit, ctx);
535 
536 	args->fence = submit->fence->seqno;
537 
538 	if (args->flags & MSM_SUBMIT_FENCE_FD_OUT) {
539 		fd_install(out_fence_fd, sync_file->file);
540 		args->fence_fd = out_fence_fd;
541 	}
542 
543 out:
544 	if (in_fence)
545 		fence_put(in_fence);
546 	submit_cleanup(submit);
547 	if (ret)
548 		msm_gem_submit_free(submit);
549 out_unlock:
550 	if (ret && (out_fence_fd >= 0))
551 		put_unused_fd(out_fence_fd);
552 	priv->struct_mutex_task = NULL;
553 	mutex_unlock(&dev->struct_mutex);
554 	return ret;
555 }
556