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 "msm_drv.h"
19#include "msm_gpu.h"
20#include "msm_gem.h"
21
22/*
23 * Cmdstream submission:
24 */
25
26/* make sure these don't conflict w/ MSM_SUBMIT_BO_x */
27#define BO_VALID    0x8000
28#define BO_LOCKED   0x4000
29#define BO_PINNED   0x2000
30
31static inline void __user *to_user_ptr(u64 address)
32{
33	return (void __user *)(uintptr_t)address;
34}
35
36static struct msm_gem_submit *submit_create(struct drm_device *dev,
37		struct msm_gpu *gpu, int nr)
38{
39	struct msm_gem_submit *submit;
40	int sz = sizeof(*submit) + (nr * sizeof(submit->bos[0]));
41
42	submit = kmalloc(sz, GFP_TEMPORARY | __GFP_NOWARN | __GFP_NORETRY);
43	if (submit) {
44		submit->dev = dev;
45		submit->gpu = gpu;
46
47		/* initially, until copy_from_user() and bo lookup succeeds: */
48		submit->nr_bos = 0;
49		submit->nr_cmds = 0;
50
51		INIT_LIST_HEAD(&submit->bo_list);
52		ww_acquire_init(&submit->ticket, &reservation_ww_class);
53	}
54
55	return submit;
56}
57
58static int submit_lookup_objects(struct msm_gem_submit *submit,
59		struct drm_msm_gem_submit *args, struct drm_file *file)
60{
61	unsigned i;
62	int ret = 0;
63
64	spin_lock(&file->table_lock);
65
66	for (i = 0; i < args->nr_bos; i++) {
67		struct drm_msm_gem_submit_bo submit_bo;
68		struct drm_gem_object *obj;
69		struct msm_gem_object *msm_obj;
70		void __user *userptr =
71			to_user_ptr(args->bos + (i * sizeof(submit_bo)));
72
73		ret = copy_from_user(&submit_bo, userptr, sizeof(submit_bo));
74		if (ret) {
75			ret = -EFAULT;
76			goto out_unlock;
77		}
78
79		if (submit_bo.flags & ~MSM_SUBMIT_BO_FLAGS) {
80			DRM_ERROR("invalid flags: %x\n", submit_bo.flags);
81			ret = -EINVAL;
82			goto out_unlock;
83		}
84
85		submit->bos[i].flags = submit_bo.flags;
86		/* in validate_objects() we figure out if this is true: */
87		submit->bos[i].iova  = submit_bo.presumed;
88
89		/* normally use drm_gem_object_lookup(), but for bulk lookup
90		 * all under single table_lock just hit object_idr directly:
91		 */
92		obj = idr_find(&file->object_idr, submit_bo.handle);
93		if (!obj) {
94			DRM_ERROR("invalid handle %u at index %u\n", submit_bo.handle, i);
95			ret = -EINVAL;
96			goto out_unlock;
97		}
98
99		msm_obj = to_msm_bo(obj);
100
101		if (!list_empty(&msm_obj->submit_entry)) {
102			DRM_ERROR("handle %u at index %u already on submit list\n",
103					submit_bo.handle, i);
104			ret = -EINVAL;
105			goto out_unlock;
106		}
107
108		drm_gem_object_reference(obj);
109
110		submit->bos[i].obj = msm_obj;
111
112		list_add_tail(&msm_obj->submit_entry, &submit->bo_list);
113	}
114
115out_unlock:
116	submit->nr_bos = i;
117	spin_unlock(&file->table_lock);
118
119	return ret;
120}
121
122static void submit_unlock_unpin_bo(struct msm_gem_submit *submit, int i)
123{
124	struct msm_gem_object *msm_obj = submit->bos[i].obj;
125
126	if (submit->bos[i].flags & BO_PINNED)
127		msm_gem_put_iova(&msm_obj->base, submit->gpu->id);
128
129	if (submit->bos[i].flags & BO_LOCKED)
130		ww_mutex_unlock(&msm_obj->resv->lock);
131
132	if (!(submit->bos[i].flags & BO_VALID))
133		submit->bos[i].iova = 0;
134
135	submit->bos[i].flags &= ~(BO_LOCKED | BO_PINNED);
136}
137
138/* This is where we make sure all the bo's are reserved and pin'd: */
139static int submit_validate_objects(struct msm_gem_submit *submit)
140{
141	int contended, slow_locked = -1, i, ret = 0;
142
143retry:
144	submit->valid = true;
145
146	for (i = 0; i < submit->nr_bos; i++) {
147		struct msm_gem_object *msm_obj = submit->bos[i].obj;
148		uint32_t iova;
149
150		if (slow_locked == i)
151			slow_locked = -1;
152
153		contended = i;
154
155		if (!(submit->bos[i].flags & BO_LOCKED)) {
156			ret = ww_mutex_lock_interruptible(&msm_obj->resv->lock,
157					&submit->ticket);
158			if (ret)
159				goto fail;
160			submit->bos[i].flags |= BO_LOCKED;
161		}
162
163
164		/* if locking succeeded, pin bo: */
165		ret = msm_gem_get_iova_locked(&msm_obj->base,
166				submit->gpu->id, &iova);
167
168		/* this would break the logic in the fail path.. there is no
169		 * reason for this to happen, but just to be on the safe side
170		 * let's notice if this starts happening in the future:
171		 */
172		WARN_ON(ret == -EDEADLK);
173
174		if (ret)
175			goto fail;
176
177		submit->bos[i].flags |= BO_PINNED;
178
179		if (iova == submit->bos[i].iova) {
180			submit->bos[i].flags |= BO_VALID;
181		} else {
182			submit->bos[i].iova = iova;
183			submit->bos[i].flags &= ~BO_VALID;
184			submit->valid = false;
185		}
186	}
187
188	ww_acquire_done(&submit->ticket);
189
190	return 0;
191
192fail:
193	for (; i >= 0; i--)
194		submit_unlock_unpin_bo(submit, i);
195
196	if (slow_locked > 0)
197		submit_unlock_unpin_bo(submit, slow_locked);
198
199	if (ret == -EDEADLK) {
200		struct msm_gem_object *msm_obj = submit->bos[contended].obj;
201		/* we lost out in a seqno race, lock and retry.. */
202		ret = ww_mutex_lock_slow_interruptible(&msm_obj->resv->lock,
203				&submit->ticket);
204		if (!ret) {
205			submit->bos[contended].flags |= BO_LOCKED;
206			slow_locked = contended;
207			goto retry;
208		}
209	}
210
211	return ret;
212}
213
214static int submit_bo(struct msm_gem_submit *submit, uint32_t idx,
215		struct msm_gem_object **obj, uint32_t *iova, bool *valid)
216{
217	if (idx >= submit->nr_bos) {
218		DRM_ERROR("invalid buffer index: %u (out of %u)\n",
219				idx, submit->nr_bos);
220		return -EINVAL;
221	}
222
223	if (obj)
224		*obj = submit->bos[idx].obj;
225	if (iova)
226		*iova = submit->bos[idx].iova;
227	if (valid)
228		*valid = !!(submit->bos[idx].flags & BO_VALID);
229
230	return 0;
231}
232
233/* process the reloc's and patch up the cmdstream as needed: */
234static int submit_reloc(struct msm_gem_submit *submit, struct msm_gem_object *obj,
235		uint32_t offset, uint32_t nr_relocs, uint64_t relocs)
236{
237	uint32_t i, last_offset = 0;
238	uint32_t *ptr;
239	int ret;
240
241	if (offset % 4) {
242		DRM_ERROR("non-aligned cmdstream buffer: %u\n", offset);
243		return -EINVAL;
244	}
245
246	/* For now, just map the entire thing.  Eventually we probably
247	 * to do it page-by-page, w/ kmap() if not vmap()d..
248	 */
249	ptr = msm_gem_vaddr_locked(&obj->base);
250
251	if (IS_ERR(ptr)) {
252		ret = PTR_ERR(ptr);
253		DBG("failed to map: %d", ret);
254		return ret;
255	}
256
257	for (i = 0; i < nr_relocs; i++) {
258		struct drm_msm_gem_submit_reloc submit_reloc;
259		void __user *userptr =
260			to_user_ptr(relocs + (i * sizeof(submit_reloc)));
261		uint32_t iova, off;
262		bool valid;
263
264		ret = copy_from_user(&submit_reloc, userptr, sizeof(submit_reloc));
265		if (ret)
266			return -EFAULT;
267
268		if (submit_reloc.submit_offset % 4) {
269			DRM_ERROR("non-aligned reloc offset: %u\n",
270					submit_reloc.submit_offset);
271			return -EINVAL;
272		}
273
274		/* offset in dwords: */
275		off = submit_reloc.submit_offset / 4;
276
277		if ((off >= (obj->base.size / 4)) ||
278				(off < last_offset)) {
279			DRM_ERROR("invalid offset %u at reloc %u\n", off, i);
280			return -EINVAL;
281		}
282
283		ret = submit_bo(submit, submit_reloc.reloc_idx, NULL, &iova, &valid);
284		if (ret)
285			return ret;
286
287		if (valid)
288			continue;
289
290		iova += submit_reloc.reloc_offset;
291
292		if (submit_reloc.shift < 0)
293			iova >>= -submit_reloc.shift;
294		else
295			iova <<= submit_reloc.shift;
296
297		ptr[off] = iova | submit_reloc.or;
298
299		last_offset = off;
300	}
301
302	return 0;
303}
304
305static void submit_cleanup(struct msm_gem_submit *submit, bool fail)
306{
307	unsigned i;
308
309	for (i = 0; i < submit->nr_bos; i++) {
310		struct msm_gem_object *msm_obj = submit->bos[i].obj;
311		submit_unlock_unpin_bo(submit, i);
312		list_del_init(&msm_obj->submit_entry);
313		drm_gem_object_unreference(&msm_obj->base);
314	}
315
316	ww_acquire_fini(&submit->ticket);
317}
318
319int msm_ioctl_gem_submit(struct drm_device *dev, void *data,
320		struct drm_file *file)
321{
322	struct msm_drm_private *priv = dev->dev_private;
323	struct drm_msm_gem_submit *args = data;
324	struct msm_file_private *ctx = file->driver_priv;
325	struct msm_gem_submit *submit;
326	struct msm_gpu *gpu;
327	unsigned i;
328	int ret;
329
330	/* for now, we just have 3d pipe.. eventually this would need to
331	 * be more clever to dispatch to appropriate gpu module:
332	 */
333	if (args->pipe != MSM_PIPE_3D0)
334		return -EINVAL;
335
336	gpu = priv->gpu;
337
338	if (args->nr_cmds > MAX_CMDS)
339		return -EINVAL;
340
341	mutex_lock(&dev->struct_mutex);
342
343	submit = submit_create(dev, gpu, args->nr_bos);
344	if (!submit) {
345		ret = -ENOMEM;
346		goto out;
347	}
348
349	ret = submit_lookup_objects(submit, args, file);
350	if (ret)
351		goto out;
352
353	ret = submit_validate_objects(submit);
354	if (ret)
355		goto out;
356
357	for (i = 0; i < args->nr_cmds; i++) {
358		struct drm_msm_gem_submit_cmd submit_cmd;
359		void __user *userptr =
360			to_user_ptr(args->cmds + (i * sizeof(submit_cmd)));
361		struct msm_gem_object *msm_obj;
362		uint32_t iova;
363
364		ret = copy_from_user(&submit_cmd, userptr, sizeof(submit_cmd));
365		if (ret) {
366			ret = -EFAULT;
367			goto out;
368		}
369
370		/* validate input from userspace: */
371		switch (submit_cmd.type) {
372		case MSM_SUBMIT_CMD_BUF:
373		case MSM_SUBMIT_CMD_IB_TARGET_BUF:
374		case MSM_SUBMIT_CMD_CTX_RESTORE_BUF:
375			break;
376		default:
377			DRM_ERROR("invalid type: %08x\n", submit_cmd.type);
378			ret = -EINVAL;
379			goto out;
380		}
381
382		ret = submit_bo(submit, submit_cmd.submit_idx,
383				&msm_obj, &iova, NULL);
384		if (ret)
385			goto out;
386
387		if (submit_cmd.size % 4) {
388			DRM_ERROR("non-aligned cmdstream buffer size: %u\n",
389					submit_cmd.size);
390			ret = -EINVAL;
391			goto out;
392		}
393
394		if ((submit_cmd.size + submit_cmd.submit_offset) >=
395				msm_obj->base.size) {
396			DRM_ERROR("invalid cmdstream size: %u\n", submit_cmd.size);
397			ret = -EINVAL;
398			goto out;
399		}
400
401		submit->cmd[i].type = submit_cmd.type;
402		submit->cmd[i].size = submit_cmd.size / 4;
403		submit->cmd[i].iova = iova + submit_cmd.submit_offset;
404		submit->cmd[i].idx  = submit_cmd.submit_idx;
405
406		if (submit->valid)
407			continue;
408
409		ret = submit_reloc(submit, msm_obj, submit_cmd.submit_offset,
410				submit_cmd.nr_relocs, submit_cmd.relocs);
411		if (ret)
412			goto out;
413	}
414
415	submit->nr_cmds = i;
416
417	ret = msm_gpu_submit(gpu, submit, ctx);
418
419	args->fence = submit->fence;
420
421out:
422	if (submit)
423		submit_cleanup(submit, !!ret);
424	mutex_unlock(&dev->struct_mutex);
425	return ret;
426}
427