1// SPDX-License-Identifier: MIT
2
3#include "nouveau_drv.h"
4#include "nouveau_gem.h"
5#include "nouveau_mem.h"
6#include "nouveau_dma.h"
7#include "nouveau_exec.h"
8#include "nouveau_abi16.h"
9#include "nouveau_chan.h"
10#include "nouveau_sched.h"
11#include "nouveau_uvmm.h"
12
13/**
14 * DOC: Overview
15 *
16 * Nouveau's VM_BIND / EXEC UAPI consists of three ioctls: DRM_NOUVEAU_VM_INIT,
17 * DRM_NOUVEAU_VM_BIND and DRM_NOUVEAU_EXEC.
18 *
19 * In order to use the UAPI firstly a user client must initialize the VA space
20 * using the DRM_NOUVEAU_VM_INIT ioctl specifying which region of the VA space
21 * should be managed by the kernel and which by the UMD.
22 *
23 * The DRM_NOUVEAU_VM_BIND ioctl provides clients an interface to manage the
24 * userspace-managable portion of the VA space. It provides operations to map
25 * and unmap memory. Mappings may be flagged as sparse. Sparse mappings are not
26 * backed by a GEM object and the kernel will ignore GEM handles provided
27 * alongside a sparse mapping.
28 *
29 * Userspace may request memory backed mappings either within or outside of the
30 * bounds (but not crossing those bounds) of a previously mapped sparse
31 * mapping. Subsequently requested memory backed mappings within a sparse
32 * mapping will take precedence over the corresponding range of the sparse
33 * mapping. If such memory backed mappings are unmapped the kernel will make
34 * sure that the corresponding sparse mapping will take their place again.
35 * Requests to unmap a sparse mapping that still contains memory backed mappings
36 * will result in those memory backed mappings being unmapped first.
37 *
38 * Unmap requests are not bound to the range of existing mappings and can even
39 * overlap the bounds of sparse mappings. For such a request the kernel will
40 * make sure to unmap all memory backed mappings within the given range,
41 * splitting up memory backed mappings which are only partially contained
42 * within the given range. Unmap requests with the sparse flag set must match
43 * the range of a previously mapped sparse mapping exactly though.
44 *
45 * While the kernel generally permits arbitrary sequences and ranges of memory
46 * backed mappings being mapped and unmapped, either within a single or multiple
47 * VM_BIND ioctl calls, there are some restrictions for sparse mappings.
48 *
49 * The kernel does not permit to:
50 *   - unmap non-existent sparse mappings
51 *   - unmap a sparse mapping and map a new sparse mapping overlapping the range
52 *     of the previously unmapped sparse mapping within the same VM_BIND ioctl
53 *   - unmap a sparse mapping and map new memory backed mappings overlapping the
54 *     range of the previously unmapped sparse mapping within the same VM_BIND
55 *     ioctl
56 *
57 * When using the VM_BIND ioctl to request the kernel to map memory to a given
58 * virtual address in the GPU's VA space there is no guarantee that the actual
59 * mappings are created in the GPU's MMU. If the given memory is swapped out
60 * at the time the bind operation is executed the kernel will stash the mapping
61 * details into it's internal alloctor and create the actual MMU mappings once
62 * the memory is swapped back in. While this is transparent for userspace, it is
63 * guaranteed that all the backing memory is swapped back in and all the memory
64 * mappings, as requested by userspace previously, are actually mapped once the
65 * DRM_NOUVEAU_EXEC ioctl is called to submit an exec job.
66 *
67 * A VM_BIND job can be executed either synchronously or asynchronously. If
68 * exectued asynchronously, userspace may provide a list of syncobjs this job
69 * will wait for and/or a list of syncobj the kernel will signal once the
70 * VM_BIND job finished execution. If executed synchronously the ioctl will
71 * block until the bind job is finished. For synchronous jobs the kernel will
72 * not permit any syncobjs submitted to the kernel.
73 *
74 * To execute a push buffer the UAPI provides the DRM_NOUVEAU_EXEC ioctl. EXEC
75 * jobs are always executed asynchronously, and, equal to VM_BIND jobs, provide
76 * the option to synchronize them with syncobjs.
77 *
78 * Besides that, EXEC jobs can be scheduled for a specified channel to execute on.
79 *
80 * Since VM_BIND jobs update the GPU's VA space on job submit, EXEC jobs do have
81 * an up to date view of the VA space. However, the actual mappings might still
82 * be pending. Hence, EXEC jobs require to have the particular fences - of
83 * the corresponding VM_BIND jobs they depent on - attached to them.
84 */
85
86static int
87nouveau_exec_job_submit(struct nouveau_job *job,
88			struct drm_gpuvm_exec *vme)
89{
90	struct nouveau_exec_job *exec_job = to_nouveau_exec_job(job);
91	struct nouveau_cli *cli = job->cli;
92	struct nouveau_uvmm *uvmm = nouveau_cli_uvmm(cli);
93	int ret;
94
95	/* Create a new fence, but do not emit yet. */
96	ret = nouveau_fence_create(&exec_job->fence, exec_job->chan);
97	if (ret)
98		return ret;
99
100	nouveau_uvmm_lock(uvmm);
101	ret = drm_gpuvm_exec_lock(vme);
102	if (ret) {
103		nouveau_uvmm_unlock(uvmm);
104		return ret;
105	}
106	nouveau_uvmm_unlock(uvmm);
107
108	ret = drm_gpuvm_exec_validate(vme);
109	if (ret) {
110		drm_gpuvm_exec_unlock(vme);
111		return ret;
112	}
113
114	return 0;
115}
116
117static void
118nouveau_exec_job_armed_submit(struct nouveau_job *job,
119			      struct drm_gpuvm_exec *vme)
120{
121	drm_gpuvm_exec_resv_add_fence(vme, job->done_fence,
122				      job->resv_usage, job->resv_usage);
123	drm_gpuvm_exec_unlock(vme);
124}
125
126static struct dma_fence *
127nouveau_exec_job_run(struct nouveau_job *job)
128{
129	struct nouveau_exec_job *exec_job = to_nouveau_exec_job(job);
130	struct nouveau_channel *chan = exec_job->chan;
131	struct nouveau_fence *fence = exec_job->fence;
132	int i, ret;
133
134	ret = nouveau_dma_wait(chan, exec_job->push.count + 1, 16);
135	if (ret) {
136		NV_PRINTK(err, job->cli, "nv50cal_space: %d\n", ret);
137		return ERR_PTR(ret);
138	}
139
140	for (i = 0; i < exec_job->push.count; i++) {
141		struct drm_nouveau_exec_push *p = &exec_job->push.s[i];
142		bool no_prefetch = p->flags & DRM_NOUVEAU_EXEC_PUSH_NO_PREFETCH;
143
144		nv50_dma_push(chan, p->va, p->va_len, no_prefetch);
145	}
146
147	ret = nouveau_fence_emit(fence);
148	if (ret) {
149		nouveau_fence_unref(&exec_job->fence);
150		NV_PRINTK(err, job->cli, "error fencing pushbuf: %d\n", ret);
151		WIND_RING(chan);
152		return ERR_PTR(ret);
153	}
154
155	/* The fence was emitted successfully, set the job's fence pointer to
156	 * NULL in order to avoid freeing it up when the job is cleaned up.
157	 */
158	exec_job->fence = NULL;
159
160	return &fence->base;
161}
162
163static void
164nouveau_exec_job_free(struct nouveau_job *job)
165{
166	struct nouveau_exec_job *exec_job = to_nouveau_exec_job(job);
167
168	nouveau_job_done(job);
169	nouveau_job_free(job);
170
171	kfree(exec_job->fence);
172	kfree(exec_job->push.s);
173	kfree(exec_job);
174}
175
176static enum drm_gpu_sched_stat
177nouveau_exec_job_timeout(struct nouveau_job *job)
178{
179	struct nouveau_exec_job *exec_job = to_nouveau_exec_job(job);
180	struct nouveau_channel *chan = exec_job->chan;
181
182	if (unlikely(!atomic_read(&chan->killed)))
183		nouveau_channel_kill(chan);
184
185	NV_PRINTK(warn, job->cli, "job timeout, channel %d killed!\n",
186		  chan->chid);
187
188	return DRM_GPU_SCHED_STAT_NOMINAL;
189}
190
191static struct nouveau_job_ops nouveau_exec_job_ops = {
192	.submit = nouveau_exec_job_submit,
193	.armed_submit = nouveau_exec_job_armed_submit,
194	.run = nouveau_exec_job_run,
195	.free = nouveau_exec_job_free,
196	.timeout = nouveau_exec_job_timeout,
197};
198
199int
200nouveau_exec_job_init(struct nouveau_exec_job **pjob,
201		      struct nouveau_exec_job_args *__args)
202{
203	struct nouveau_exec_job *job;
204	struct nouveau_job_args args = {};
205	int i, ret;
206
207	for (i = 0; i < __args->push.count; i++) {
208		struct drm_nouveau_exec_push *p = &__args->push.s[i];
209
210		if (unlikely(p->va_len > NV50_DMA_PUSH_MAX_LENGTH)) {
211			NV_PRINTK(err, nouveau_cli(__args->file_priv),
212				  "pushbuf size exceeds limit: 0x%x max 0x%x\n",
213				  p->va_len, NV50_DMA_PUSH_MAX_LENGTH);
214			return -EINVAL;
215		}
216	}
217
218	job = *pjob = kzalloc(sizeof(*job), GFP_KERNEL);
219	if (!job)
220		return -ENOMEM;
221
222	job->push.count = __args->push.count;
223	if (__args->push.count) {
224		job->push.s = kmemdup(__args->push.s,
225				      sizeof(*__args->push.s) *
226				      __args->push.count,
227				      GFP_KERNEL);
228		if (!job->push.s) {
229			ret = -ENOMEM;
230			goto err_free_job;
231		}
232	}
233
234	args.file_priv = __args->file_priv;
235	job->chan = __args->chan;
236
237	args.sched = __args->sched;
238	/* Plus one to account for the HW fence. */
239	args.credits = job->push.count + 1;
240
241	args.in_sync.count = __args->in_sync.count;
242	args.in_sync.s = __args->in_sync.s;
243
244	args.out_sync.count = __args->out_sync.count;
245	args.out_sync.s = __args->out_sync.s;
246
247	args.ops = &nouveau_exec_job_ops;
248	args.resv_usage = DMA_RESV_USAGE_WRITE;
249
250	ret = nouveau_job_init(&job->base, &args);
251	if (ret)
252		goto err_free_pushs;
253
254	return 0;
255
256err_free_pushs:
257	kfree(job->push.s);
258err_free_job:
259	kfree(job);
260	*pjob = NULL;
261
262	return ret;
263}
264
265static int
266nouveau_exec(struct nouveau_exec_job_args *args)
267{
268	struct nouveau_exec_job *job;
269	int ret;
270
271	ret = nouveau_exec_job_init(&job, args);
272	if (ret)
273		return ret;
274
275	ret = nouveau_job_submit(&job->base);
276	if (ret)
277		goto err_job_fini;
278
279	return 0;
280
281err_job_fini:
282	nouveau_job_fini(&job->base);
283	return ret;
284}
285
286static int
287nouveau_exec_ucopy(struct nouveau_exec_job_args *args,
288		   struct drm_nouveau_exec *req)
289{
290	struct drm_nouveau_sync **s;
291	u32 inc = req->wait_count;
292	u64 ins = req->wait_ptr;
293	u32 outc = req->sig_count;
294	u64 outs = req->sig_ptr;
295	u32 pushc = req->push_count;
296	u64 pushs = req->push_ptr;
297	int ret;
298
299	if (pushc) {
300		args->push.count = pushc;
301		args->push.s = u_memcpya(pushs, pushc, sizeof(*args->push.s));
302		if (IS_ERR(args->push.s))
303			return PTR_ERR(args->push.s);
304	}
305
306	if (inc) {
307		s = &args->in_sync.s;
308
309		args->in_sync.count = inc;
310		*s = u_memcpya(ins, inc, sizeof(**s));
311		if (IS_ERR(*s)) {
312			ret = PTR_ERR(*s);
313			goto err_free_pushs;
314		}
315	}
316
317	if (outc) {
318		s = &args->out_sync.s;
319
320		args->out_sync.count = outc;
321		*s = u_memcpya(outs, outc, sizeof(**s));
322		if (IS_ERR(*s)) {
323			ret = PTR_ERR(*s);
324			goto err_free_ins;
325		}
326	}
327
328	return 0;
329
330err_free_pushs:
331	u_free(args->push.s);
332err_free_ins:
333	u_free(args->in_sync.s);
334	return ret;
335}
336
337static void
338nouveau_exec_ufree(struct nouveau_exec_job_args *args)
339{
340	u_free(args->push.s);
341	u_free(args->in_sync.s);
342	u_free(args->out_sync.s);
343}
344
345int
346nouveau_exec_ioctl_exec(struct drm_device *dev,
347			void *data,
348			struct drm_file *file_priv)
349{
350	struct nouveau_abi16 *abi16 = nouveau_abi16_get(file_priv);
351	struct nouveau_cli *cli = nouveau_cli(file_priv);
352	struct nouveau_abi16_chan *chan16;
353	struct nouveau_channel *chan = NULL;
354	struct nouveau_exec_job_args args = {};
355	struct drm_nouveau_exec *req = data;
356	int push_max, ret = 0;
357
358	if (unlikely(!abi16))
359		return -ENOMEM;
360
361	/* abi16 locks already */
362	if (unlikely(!nouveau_cli_uvmm(cli)))
363		return nouveau_abi16_put(abi16, -ENOSYS);
364
365	list_for_each_entry(chan16, &abi16->channels, head) {
366		if (chan16->chan->chid == req->channel) {
367			chan = chan16->chan;
368			break;
369		}
370	}
371
372	if (!chan)
373		return nouveau_abi16_put(abi16, -ENOENT);
374
375	if (unlikely(atomic_read(&chan->killed)))
376		return nouveau_abi16_put(abi16, -ENODEV);
377
378	if (!chan->dma.ib_max)
379		return nouveau_abi16_put(abi16, -ENOSYS);
380
381	push_max = nouveau_exec_push_max_from_ib_max(chan->dma.ib_max);
382	if (unlikely(req->push_count > push_max)) {
383		NV_PRINTK(err, cli, "pushbuf push count exceeds limit: %d max %d\n",
384			  req->push_count, push_max);
385		return nouveau_abi16_put(abi16, -EINVAL);
386	}
387
388	ret = nouveau_exec_ucopy(&args, req);
389	if (ret)
390		goto out;
391
392	args.sched = chan16->sched;
393	args.file_priv = file_priv;
394	args.chan = chan;
395
396	ret = nouveau_exec(&args);
397	if (ret)
398		goto out_free_args;
399
400out_free_args:
401	nouveau_exec_ufree(&args);
402out:
403	return nouveau_abi16_put(abi16, ret);
404}
405