xref: /linux/drivers/dma/dmatest.c (revision 293d5b43948309434568f4dcbb36cce4c3c51bd5)
1 /*
2  * DMA Engine test module
3  *
4  * Copyright (C) 2007 Atmel Corporation
5  * Copyright (C) 2013 Intel Corporation
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12 
13 #include <linux/delay.h>
14 #include <linux/dma-mapping.h>
15 #include <linux/dmaengine.h>
16 #include <linux/freezer.h>
17 #include <linux/init.h>
18 #include <linux/kthread.h>
19 #include <linux/module.h>
20 #include <linux/moduleparam.h>
21 #include <linux/random.h>
22 #include <linux/slab.h>
23 #include <linux/wait.h>
24 
25 static unsigned int test_buf_size = 16384;
26 module_param(test_buf_size, uint, S_IRUGO | S_IWUSR);
27 MODULE_PARM_DESC(test_buf_size, "Size of the memcpy test buffer");
28 
29 static char test_channel[20];
30 module_param_string(channel, test_channel, sizeof(test_channel),
31 		S_IRUGO | S_IWUSR);
32 MODULE_PARM_DESC(channel, "Bus ID of the channel to test (default: any)");
33 
34 static char test_device[32];
35 module_param_string(device, test_device, sizeof(test_device),
36 		S_IRUGO | S_IWUSR);
37 MODULE_PARM_DESC(device, "Bus ID of the DMA Engine to test (default: any)");
38 
39 static unsigned int threads_per_chan = 1;
40 module_param(threads_per_chan, uint, S_IRUGO | S_IWUSR);
41 MODULE_PARM_DESC(threads_per_chan,
42 		"Number of threads to start per channel (default: 1)");
43 
44 static unsigned int max_channels;
45 module_param(max_channels, uint, S_IRUGO | S_IWUSR);
46 MODULE_PARM_DESC(max_channels,
47 		"Maximum number of channels to use (default: all)");
48 
49 static unsigned int iterations;
50 module_param(iterations, uint, S_IRUGO | S_IWUSR);
51 MODULE_PARM_DESC(iterations,
52 		"Iterations before stopping test (default: infinite)");
53 
54 static unsigned int sg_buffers = 1;
55 module_param(sg_buffers, uint, S_IRUGO | S_IWUSR);
56 MODULE_PARM_DESC(sg_buffers,
57 		"Number of scatter gather buffers (default: 1)");
58 
59 static unsigned int dmatest = 1;
60 module_param(dmatest, uint, S_IRUGO | S_IWUSR);
61 MODULE_PARM_DESC(dmatest,
62 		"dmatest 0-memcpy 1-slave_sg (default: 1)");
63 
64 static unsigned int xor_sources = 3;
65 module_param(xor_sources, uint, S_IRUGO | S_IWUSR);
66 MODULE_PARM_DESC(xor_sources,
67 		"Number of xor source buffers (default: 3)");
68 
69 static unsigned int pq_sources = 3;
70 module_param(pq_sources, uint, S_IRUGO | S_IWUSR);
71 MODULE_PARM_DESC(pq_sources,
72 		"Number of p+q source buffers (default: 3)");
73 
74 static int timeout = 3000;
75 module_param(timeout, uint, S_IRUGO | S_IWUSR);
76 MODULE_PARM_DESC(timeout, "Transfer Timeout in msec (default: 3000), "
77 		 "Pass -1 for infinite timeout");
78 
79 static bool noverify;
80 module_param(noverify, bool, S_IRUGO | S_IWUSR);
81 MODULE_PARM_DESC(noverify, "Disable random data setup and verification");
82 
83 static bool verbose;
84 module_param(verbose, bool, S_IRUGO | S_IWUSR);
85 MODULE_PARM_DESC(verbose, "Enable \"success\" result messages (default: off)");
86 
87 /**
88  * struct dmatest_params - test parameters.
89  * @buf_size:		size of the memcpy test buffer
90  * @channel:		bus ID of the channel to test
91  * @device:		bus ID of the DMA Engine to test
92  * @threads_per_chan:	number of threads to start per channel
93  * @max_channels:	maximum number of channels to use
94  * @iterations:		iterations before stopping test
95  * @xor_sources:	number of xor source buffers
96  * @pq_sources:		number of p+q source buffers
97  * @timeout:		transfer timeout in msec, -1 for infinite timeout
98  */
99 struct dmatest_params {
100 	unsigned int	buf_size;
101 	char		channel[20];
102 	char		device[32];
103 	unsigned int	threads_per_chan;
104 	unsigned int	max_channels;
105 	unsigned int	iterations;
106 	unsigned int	xor_sources;
107 	unsigned int	pq_sources;
108 	int		timeout;
109 	bool		noverify;
110 };
111 
112 /**
113  * struct dmatest_info - test information.
114  * @params:		test parameters
115  * @lock:		access protection to the fields of this structure
116  */
117 static struct dmatest_info {
118 	/* Test parameters */
119 	struct dmatest_params	params;
120 
121 	/* Internal state */
122 	struct list_head	channels;
123 	unsigned int		nr_channels;
124 	struct mutex		lock;
125 	bool			did_init;
126 } test_info = {
127 	.channels = LIST_HEAD_INIT(test_info.channels),
128 	.lock = __MUTEX_INITIALIZER(test_info.lock),
129 };
130 
131 static int dmatest_run_set(const char *val, const struct kernel_param *kp);
132 static int dmatest_run_get(char *val, const struct kernel_param *kp);
133 static const struct kernel_param_ops run_ops = {
134 	.set = dmatest_run_set,
135 	.get = dmatest_run_get,
136 };
137 static bool dmatest_run;
138 module_param_cb(run, &run_ops, &dmatest_run, S_IRUGO | S_IWUSR);
139 MODULE_PARM_DESC(run, "Run the test (default: false)");
140 
141 /* Maximum amount of mismatched bytes in buffer to print */
142 #define MAX_ERROR_COUNT		32
143 
144 /*
145  * Initialization patterns. All bytes in the source buffer has bit 7
146  * set, all bytes in the destination buffer has bit 7 cleared.
147  *
148  * Bit 6 is set for all bytes which are to be copied by the DMA
149  * engine. Bit 5 is set for all bytes which are to be overwritten by
150  * the DMA engine.
151  *
152  * The remaining bits are the inverse of a counter which increments by
153  * one for each byte address.
154  */
155 #define PATTERN_SRC		0x80
156 #define PATTERN_DST		0x00
157 #define PATTERN_COPY		0x40
158 #define PATTERN_OVERWRITE	0x20
159 #define PATTERN_COUNT_MASK	0x1f
160 
161 struct dmatest_thread {
162 	struct list_head	node;
163 	struct dmatest_info	*info;
164 	struct task_struct	*task;
165 	struct dma_chan		*chan;
166 	u8			**srcs;
167 	u8			**dsts;
168 	enum dma_transaction_type type;
169 	bool			done;
170 };
171 
172 struct dmatest_chan {
173 	struct list_head	node;
174 	struct dma_chan		*chan;
175 	struct list_head	threads;
176 };
177 
178 static DECLARE_WAIT_QUEUE_HEAD(thread_wait);
179 static bool wait;
180 
181 static bool is_threaded_test_run(struct dmatest_info *info)
182 {
183 	struct dmatest_chan *dtc;
184 
185 	list_for_each_entry(dtc, &info->channels, node) {
186 		struct dmatest_thread *thread;
187 
188 		list_for_each_entry(thread, &dtc->threads, node) {
189 			if (!thread->done)
190 				return true;
191 		}
192 	}
193 
194 	return false;
195 }
196 
197 static int dmatest_wait_get(char *val, const struct kernel_param *kp)
198 {
199 	struct dmatest_info *info = &test_info;
200 	struct dmatest_params *params = &info->params;
201 
202 	if (params->iterations)
203 		wait_event(thread_wait, !is_threaded_test_run(info));
204 	wait = true;
205 	return param_get_bool(val, kp);
206 }
207 
208 static const struct kernel_param_ops wait_ops = {
209 	.get = dmatest_wait_get,
210 	.set = param_set_bool,
211 };
212 module_param_cb(wait, &wait_ops, &wait, S_IRUGO);
213 MODULE_PARM_DESC(wait, "Wait for tests to complete (default: false)");
214 
215 static bool dmatest_match_channel(struct dmatest_params *params,
216 		struct dma_chan *chan)
217 {
218 	if (params->channel[0] == '\0')
219 		return true;
220 	return strcmp(dma_chan_name(chan), params->channel) == 0;
221 }
222 
223 static bool dmatest_match_device(struct dmatest_params *params,
224 		struct dma_device *device)
225 {
226 	if (params->device[0] == '\0')
227 		return true;
228 	return strcmp(dev_name(device->dev), params->device) == 0;
229 }
230 
231 static unsigned long dmatest_random(void)
232 {
233 	unsigned long buf;
234 
235 	prandom_bytes(&buf, sizeof(buf));
236 	return buf;
237 }
238 
239 static void dmatest_init_srcs(u8 **bufs, unsigned int start, unsigned int len,
240 		unsigned int buf_size)
241 {
242 	unsigned int i;
243 	u8 *buf;
244 
245 	for (; (buf = *bufs); bufs++) {
246 		for (i = 0; i < start; i++)
247 			buf[i] = PATTERN_SRC | (~i & PATTERN_COUNT_MASK);
248 		for ( ; i < start + len; i++)
249 			buf[i] = PATTERN_SRC | PATTERN_COPY
250 				| (~i & PATTERN_COUNT_MASK);
251 		for ( ; i < buf_size; i++)
252 			buf[i] = PATTERN_SRC | (~i & PATTERN_COUNT_MASK);
253 		buf++;
254 	}
255 }
256 
257 static void dmatest_init_dsts(u8 **bufs, unsigned int start, unsigned int len,
258 		unsigned int buf_size)
259 {
260 	unsigned int i;
261 	u8 *buf;
262 
263 	for (; (buf = *bufs); bufs++) {
264 		for (i = 0; i < start; i++)
265 			buf[i] = PATTERN_DST | (~i & PATTERN_COUNT_MASK);
266 		for ( ; i < start + len; i++)
267 			buf[i] = PATTERN_DST | PATTERN_OVERWRITE
268 				| (~i & PATTERN_COUNT_MASK);
269 		for ( ; i < buf_size; i++)
270 			buf[i] = PATTERN_DST | (~i & PATTERN_COUNT_MASK);
271 	}
272 }
273 
274 static void dmatest_mismatch(u8 actual, u8 pattern, unsigned int index,
275 		unsigned int counter, bool is_srcbuf)
276 {
277 	u8		diff = actual ^ pattern;
278 	u8		expected = pattern | (~counter & PATTERN_COUNT_MASK);
279 	const char	*thread_name = current->comm;
280 
281 	if (is_srcbuf)
282 		pr_warn("%s: srcbuf[0x%x] overwritten! Expected %02x, got %02x\n",
283 			thread_name, index, expected, actual);
284 	else if ((pattern & PATTERN_COPY)
285 			&& (diff & (PATTERN_COPY | PATTERN_OVERWRITE)))
286 		pr_warn("%s: dstbuf[0x%x] not copied! Expected %02x, got %02x\n",
287 			thread_name, index, expected, actual);
288 	else if (diff & PATTERN_SRC)
289 		pr_warn("%s: dstbuf[0x%x] was copied! Expected %02x, got %02x\n",
290 			thread_name, index, expected, actual);
291 	else
292 		pr_warn("%s: dstbuf[0x%x] mismatch! Expected %02x, got %02x\n",
293 			thread_name, index, expected, actual);
294 }
295 
296 static unsigned int dmatest_verify(u8 **bufs, unsigned int start,
297 		unsigned int end, unsigned int counter, u8 pattern,
298 		bool is_srcbuf)
299 {
300 	unsigned int i;
301 	unsigned int error_count = 0;
302 	u8 actual;
303 	u8 expected;
304 	u8 *buf;
305 	unsigned int counter_orig = counter;
306 
307 	for (; (buf = *bufs); bufs++) {
308 		counter = counter_orig;
309 		for (i = start; i < end; i++) {
310 			actual = buf[i];
311 			expected = pattern | (~counter & PATTERN_COUNT_MASK);
312 			if (actual != expected) {
313 				if (error_count < MAX_ERROR_COUNT)
314 					dmatest_mismatch(actual, pattern, i,
315 							 counter, is_srcbuf);
316 				error_count++;
317 			}
318 			counter++;
319 		}
320 	}
321 
322 	if (error_count > MAX_ERROR_COUNT)
323 		pr_warn("%s: %u errors suppressed\n",
324 			current->comm, error_count - MAX_ERROR_COUNT);
325 
326 	return error_count;
327 }
328 
329 /* poor man's completion - we want to use wait_event_freezable() on it */
330 struct dmatest_done {
331 	bool			done;
332 	wait_queue_head_t	*wait;
333 };
334 
335 static void dmatest_callback(void *arg)
336 {
337 	struct dmatest_done *done = arg;
338 
339 	done->done = true;
340 	wake_up_all(done->wait);
341 }
342 
343 static unsigned int min_odd(unsigned int x, unsigned int y)
344 {
345 	unsigned int val = min(x, y);
346 
347 	return val % 2 ? val : val - 1;
348 }
349 
350 static void result(const char *err, unsigned int n, unsigned int src_off,
351 		   unsigned int dst_off, unsigned int len, unsigned long data)
352 {
353 	pr_info("%s: result #%u: '%s' with src_off=0x%x dst_off=0x%x len=0x%x (%lu)\n",
354 		current->comm, n, err, src_off, dst_off, len, data);
355 }
356 
357 static void dbg_result(const char *err, unsigned int n, unsigned int src_off,
358 		       unsigned int dst_off, unsigned int len,
359 		       unsigned long data)
360 {
361 	pr_debug("%s: result #%u: '%s' with src_off=0x%x dst_off=0x%x len=0x%x (%lu)\n",
362 		 current->comm, n, err, src_off, dst_off, len, data);
363 }
364 
365 #define verbose_result(err, n, src_off, dst_off, len, data) ({	\
366 	if (verbose)						\
367 		result(err, n, src_off, dst_off, len, data);	\
368 	else							\
369 		dbg_result(err, n, src_off, dst_off, len, data);\
370 })
371 
372 static unsigned long long dmatest_persec(s64 runtime, unsigned int val)
373 {
374 	unsigned long long per_sec = 1000000;
375 
376 	if (runtime <= 0)
377 		return 0;
378 
379 	/* drop precision until runtime is 32-bits */
380 	while (runtime > UINT_MAX) {
381 		runtime >>= 1;
382 		per_sec <<= 1;
383 	}
384 
385 	per_sec *= val;
386 	do_div(per_sec, runtime);
387 	return per_sec;
388 }
389 
390 static unsigned long long dmatest_KBs(s64 runtime, unsigned long long len)
391 {
392 	return dmatest_persec(runtime, len >> 10);
393 }
394 
395 /*
396  * This function repeatedly tests DMA transfers of various lengths and
397  * offsets for a given operation type until it is told to exit by
398  * kthread_stop(). There may be multiple threads running this function
399  * in parallel for a single channel, and there may be multiple channels
400  * being tested in parallel.
401  *
402  * Before each test, the source and destination buffer is initialized
403  * with a known pattern. This pattern is different depending on
404  * whether it's in an area which is supposed to be copied or
405  * overwritten, and different in the source and destination buffers.
406  * So if the DMA engine doesn't copy exactly what we tell it to copy,
407  * we'll notice.
408  */
409 static int dmatest_func(void *data)
410 {
411 	DECLARE_WAIT_QUEUE_HEAD_ONSTACK(done_wait);
412 	struct dmatest_thread	*thread = data;
413 	struct dmatest_done	done = { .wait = &done_wait };
414 	struct dmatest_info	*info;
415 	struct dmatest_params	*params;
416 	struct dma_chan		*chan;
417 	struct dma_device	*dev;
418 	unsigned int		error_count;
419 	unsigned int		failed_tests = 0;
420 	unsigned int		total_tests = 0;
421 	dma_cookie_t		cookie;
422 	enum dma_status		status;
423 	enum dma_ctrl_flags 	flags;
424 	u8			*pq_coefs = NULL;
425 	int			ret;
426 	int			src_cnt;
427 	int			dst_cnt;
428 	int			i;
429 	ktime_t			ktime;
430 	s64			runtime = 0;
431 	unsigned long long	total_len = 0;
432 
433 	set_freezable();
434 
435 	ret = -ENOMEM;
436 
437 	smp_rmb();
438 	info = thread->info;
439 	params = &info->params;
440 	chan = thread->chan;
441 	dev = chan->device;
442 	if (thread->type == DMA_MEMCPY)
443 		src_cnt = dst_cnt = 1;
444 	else if (thread->type == DMA_SG)
445 		src_cnt = dst_cnt = sg_buffers;
446 	else if (thread->type == DMA_XOR) {
447 		/* force odd to ensure dst = src */
448 		src_cnt = min_odd(params->xor_sources | 1, dev->max_xor);
449 		dst_cnt = 1;
450 	} else if (thread->type == DMA_PQ) {
451 		/* force odd to ensure dst = src */
452 		src_cnt = min_odd(params->pq_sources | 1, dma_maxpq(dev, 0));
453 		dst_cnt = 2;
454 
455 		pq_coefs = kmalloc(params->pq_sources+1, GFP_KERNEL);
456 		if (!pq_coefs)
457 			goto err_thread_type;
458 
459 		for (i = 0; i < src_cnt; i++)
460 			pq_coefs[i] = 1;
461 	} else
462 		goto err_thread_type;
463 
464 	thread->srcs = kcalloc(src_cnt+1, sizeof(u8 *), GFP_KERNEL);
465 	if (!thread->srcs)
466 		goto err_srcs;
467 	for (i = 0; i < src_cnt; i++) {
468 		thread->srcs[i] = kmalloc(params->buf_size, GFP_KERNEL);
469 		if (!thread->srcs[i])
470 			goto err_srcbuf;
471 	}
472 	thread->srcs[i] = NULL;
473 
474 	thread->dsts = kcalloc(dst_cnt+1, sizeof(u8 *), GFP_KERNEL);
475 	if (!thread->dsts)
476 		goto err_dsts;
477 	for (i = 0; i < dst_cnt; i++) {
478 		thread->dsts[i] = kmalloc(params->buf_size, GFP_KERNEL);
479 		if (!thread->dsts[i])
480 			goto err_dstbuf;
481 	}
482 	thread->dsts[i] = NULL;
483 
484 	set_user_nice(current, 10);
485 
486 	/*
487 	 * src and dst buffers are freed by ourselves below
488 	 */
489 	flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
490 
491 	ktime = ktime_get();
492 	while (!kthread_should_stop()
493 	       && !(params->iterations && total_tests >= params->iterations)) {
494 		struct dma_async_tx_descriptor *tx = NULL;
495 		struct dmaengine_unmap_data *um;
496 		dma_addr_t srcs[src_cnt];
497 		dma_addr_t *dsts;
498 		unsigned int src_off, dst_off, len;
499 		u8 align = 0;
500 		struct scatterlist tx_sg[src_cnt];
501 		struct scatterlist rx_sg[src_cnt];
502 
503 		total_tests++;
504 
505 		/* honor alignment restrictions */
506 		if (thread->type == DMA_MEMCPY)
507 			align = dev->copy_align;
508 		else if (thread->type == DMA_XOR)
509 			align = dev->xor_align;
510 		else if (thread->type == DMA_PQ)
511 			align = dev->pq_align;
512 
513 		if (1 << align > params->buf_size) {
514 			pr_err("%u-byte buffer too small for %d-byte alignment\n",
515 			       params->buf_size, 1 << align);
516 			break;
517 		}
518 
519 		if (params->noverify)
520 			len = params->buf_size;
521 		else
522 			len = dmatest_random() % params->buf_size + 1;
523 
524 		len = (len >> align) << align;
525 		if (!len)
526 			len = 1 << align;
527 
528 		total_len += len;
529 
530 		if (params->noverify) {
531 			src_off = 0;
532 			dst_off = 0;
533 		} else {
534 			src_off = dmatest_random() % (params->buf_size - len + 1);
535 			dst_off = dmatest_random() % (params->buf_size - len + 1);
536 
537 			src_off = (src_off >> align) << align;
538 			dst_off = (dst_off >> align) << align;
539 
540 			dmatest_init_srcs(thread->srcs, src_off, len,
541 					  params->buf_size);
542 			dmatest_init_dsts(thread->dsts, dst_off, len,
543 					  params->buf_size);
544 		}
545 
546 		um = dmaengine_get_unmap_data(dev->dev, src_cnt+dst_cnt,
547 					      GFP_KERNEL);
548 		if (!um) {
549 			failed_tests++;
550 			result("unmap data NULL", total_tests,
551 			       src_off, dst_off, len, ret);
552 			continue;
553 		}
554 
555 		um->len = params->buf_size;
556 		for (i = 0; i < src_cnt; i++) {
557 			void *buf = thread->srcs[i];
558 			struct page *pg = virt_to_page(buf);
559 			unsigned pg_off = (unsigned long) buf & ~PAGE_MASK;
560 
561 			um->addr[i] = dma_map_page(dev->dev, pg, pg_off,
562 						   um->len, DMA_TO_DEVICE);
563 			srcs[i] = um->addr[i] + src_off;
564 			ret = dma_mapping_error(dev->dev, um->addr[i]);
565 			if (ret) {
566 				dmaengine_unmap_put(um);
567 				result("src mapping error", total_tests,
568 				       src_off, dst_off, len, ret);
569 				failed_tests++;
570 				continue;
571 			}
572 			um->to_cnt++;
573 		}
574 		/* map with DMA_BIDIRECTIONAL to force writeback/invalidate */
575 		dsts = &um->addr[src_cnt];
576 		for (i = 0; i < dst_cnt; i++) {
577 			void *buf = thread->dsts[i];
578 			struct page *pg = virt_to_page(buf);
579 			unsigned pg_off = (unsigned long) buf & ~PAGE_MASK;
580 
581 			dsts[i] = dma_map_page(dev->dev, pg, pg_off, um->len,
582 					       DMA_BIDIRECTIONAL);
583 			ret = dma_mapping_error(dev->dev, dsts[i]);
584 			if (ret) {
585 				dmaengine_unmap_put(um);
586 				result("dst mapping error", total_tests,
587 				       src_off, dst_off, len, ret);
588 				failed_tests++;
589 				continue;
590 			}
591 			um->bidi_cnt++;
592 		}
593 
594 		sg_init_table(tx_sg, src_cnt);
595 		sg_init_table(rx_sg, src_cnt);
596 		for (i = 0; i < src_cnt; i++) {
597 			sg_dma_address(&rx_sg[i]) = srcs[i];
598 			sg_dma_address(&tx_sg[i]) = dsts[i] + dst_off;
599 			sg_dma_len(&tx_sg[i]) = len;
600 			sg_dma_len(&rx_sg[i]) = len;
601 		}
602 
603 		if (thread->type == DMA_MEMCPY)
604 			tx = dev->device_prep_dma_memcpy(chan,
605 							 dsts[0] + dst_off,
606 							 srcs[0], len, flags);
607 		else if (thread->type == DMA_SG)
608 			tx = dev->device_prep_dma_sg(chan, tx_sg, src_cnt,
609 						     rx_sg, src_cnt, flags);
610 		else if (thread->type == DMA_XOR)
611 			tx = dev->device_prep_dma_xor(chan,
612 						      dsts[0] + dst_off,
613 						      srcs, src_cnt,
614 						      len, flags);
615 		else if (thread->type == DMA_PQ) {
616 			dma_addr_t dma_pq[dst_cnt];
617 
618 			for (i = 0; i < dst_cnt; i++)
619 				dma_pq[i] = dsts[i] + dst_off;
620 			tx = dev->device_prep_dma_pq(chan, dma_pq, srcs,
621 						     src_cnt, pq_coefs,
622 						     len, flags);
623 		}
624 
625 		if (!tx) {
626 			dmaengine_unmap_put(um);
627 			result("prep error", total_tests, src_off,
628 			       dst_off, len, ret);
629 			msleep(100);
630 			failed_tests++;
631 			continue;
632 		}
633 
634 		done.done = false;
635 		tx->callback = dmatest_callback;
636 		tx->callback_param = &done;
637 		cookie = tx->tx_submit(tx);
638 
639 		if (dma_submit_error(cookie)) {
640 			dmaengine_unmap_put(um);
641 			result("submit error", total_tests, src_off,
642 			       dst_off, len, ret);
643 			msleep(100);
644 			failed_tests++;
645 			continue;
646 		}
647 		dma_async_issue_pending(chan);
648 
649 		wait_event_freezable_timeout(done_wait, done.done,
650 					     msecs_to_jiffies(params->timeout));
651 
652 		status = dma_async_is_tx_complete(chan, cookie, NULL, NULL);
653 
654 		if (!done.done) {
655 			/*
656 			 * We're leaving the timed out dma operation with
657 			 * dangling pointer to done_wait.  To make this
658 			 * correct, we'll need to allocate wait_done for
659 			 * each test iteration and perform "who's gonna
660 			 * free it this time?" dancing.  For now, just
661 			 * leave it dangling.
662 			 */
663 			dmaengine_unmap_put(um);
664 			result("test timed out", total_tests, src_off, dst_off,
665 			       len, 0);
666 			failed_tests++;
667 			continue;
668 		} else if (status != DMA_COMPLETE) {
669 			dmaengine_unmap_put(um);
670 			result(status == DMA_ERROR ?
671 			       "completion error status" :
672 			       "completion busy status", total_tests, src_off,
673 			       dst_off, len, ret);
674 			failed_tests++;
675 			continue;
676 		}
677 
678 		dmaengine_unmap_put(um);
679 
680 		if (params->noverify) {
681 			verbose_result("test passed", total_tests, src_off,
682 				       dst_off, len, 0);
683 			continue;
684 		}
685 
686 		pr_debug("%s: verifying source buffer...\n", current->comm);
687 		error_count = dmatest_verify(thread->srcs, 0, src_off,
688 				0, PATTERN_SRC, true);
689 		error_count += dmatest_verify(thread->srcs, src_off,
690 				src_off + len, src_off,
691 				PATTERN_SRC | PATTERN_COPY, true);
692 		error_count += dmatest_verify(thread->srcs, src_off + len,
693 				params->buf_size, src_off + len,
694 				PATTERN_SRC, true);
695 
696 		pr_debug("%s: verifying dest buffer...\n", current->comm);
697 		error_count += dmatest_verify(thread->dsts, 0, dst_off,
698 				0, PATTERN_DST, false);
699 		error_count += dmatest_verify(thread->dsts, dst_off,
700 				dst_off + len, src_off,
701 				PATTERN_SRC | PATTERN_COPY, false);
702 		error_count += dmatest_verify(thread->dsts, dst_off + len,
703 				params->buf_size, dst_off + len,
704 				PATTERN_DST, false);
705 
706 		if (error_count) {
707 			result("data error", total_tests, src_off, dst_off,
708 			       len, error_count);
709 			failed_tests++;
710 		} else {
711 			verbose_result("test passed", total_tests, src_off,
712 				       dst_off, len, 0);
713 		}
714 	}
715 	runtime = ktime_us_delta(ktime_get(), ktime);
716 
717 	ret = 0;
718 err_dstbuf:
719 	for (i = 0; thread->dsts[i]; i++)
720 		kfree(thread->dsts[i]);
721 	kfree(thread->dsts);
722 err_dsts:
723 err_srcbuf:
724 	for (i = 0; thread->srcs[i]; i++)
725 		kfree(thread->srcs[i]);
726 	kfree(thread->srcs);
727 err_srcs:
728 	kfree(pq_coefs);
729 err_thread_type:
730 	pr_info("%s: summary %u tests, %u failures %llu iops %llu KB/s (%d)\n",
731 		current->comm, total_tests, failed_tests,
732 		dmatest_persec(runtime, total_tests),
733 		dmatest_KBs(runtime, total_len), ret);
734 
735 	/* terminate all transfers on specified channels */
736 	if (ret)
737 		dmaengine_terminate_all(chan);
738 
739 	thread->done = true;
740 	wake_up(&thread_wait);
741 
742 	return ret;
743 }
744 
745 static void dmatest_cleanup_channel(struct dmatest_chan *dtc)
746 {
747 	struct dmatest_thread	*thread;
748 	struct dmatest_thread	*_thread;
749 	int			ret;
750 
751 	list_for_each_entry_safe(thread, _thread, &dtc->threads, node) {
752 		ret = kthread_stop(thread->task);
753 		pr_debug("thread %s exited with status %d\n",
754 			 thread->task->comm, ret);
755 		list_del(&thread->node);
756 		put_task_struct(thread->task);
757 		kfree(thread);
758 	}
759 
760 	/* terminate all transfers on specified channels */
761 	dmaengine_terminate_all(dtc->chan);
762 
763 	kfree(dtc);
764 }
765 
766 static int dmatest_add_threads(struct dmatest_info *info,
767 		struct dmatest_chan *dtc, enum dma_transaction_type type)
768 {
769 	struct dmatest_params *params = &info->params;
770 	struct dmatest_thread *thread;
771 	struct dma_chan *chan = dtc->chan;
772 	char *op;
773 	unsigned int i;
774 
775 	if (type == DMA_MEMCPY)
776 		op = "copy";
777 	else if (type == DMA_SG)
778 		op = "sg";
779 	else if (type == DMA_XOR)
780 		op = "xor";
781 	else if (type == DMA_PQ)
782 		op = "pq";
783 	else
784 		return -EINVAL;
785 
786 	for (i = 0; i < params->threads_per_chan; i++) {
787 		thread = kzalloc(sizeof(struct dmatest_thread), GFP_KERNEL);
788 		if (!thread) {
789 			pr_warn("No memory for %s-%s%u\n",
790 				dma_chan_name(chan), op, i);
791 			break;
792 		}
793 		thread->info = info;
794 		thread->chan = dtc->chan;
795 		thread->type = type;
796 		smp_wmb();
797 		thread->task = kthread_create(dmatest_func, thread, "%s-%s%u",
798 				dma_chan_name(chan), op, i);
799 		if (IS_ERR(thread->task)) {
800 			pr_warn("Failed to create thread %s-%s%u\n",
801 				dma_chan_name(chan), op, i);
802 			kfree(thread);
803 			break;
804 		}
805 
806 		/* srcbuf and dstbuf are allocated by the thread itself */
807 		get_task_struct(thread->task);
808 		list_add_tail(&thread->node, &dtc->threads);
809 		wake_up_process(thread->task);
810 	}
811 
812 	return i;
813 }
814 
815 static int dmatest_add_channel(struct dmatest_info *info,
816 		struct dma_chan *chan)
817 {
818 	struct dmatest_chan	*dtc;
819 	struct dma_device	*dma_dev = chan->device;
820 	unsigned int		thread_count = 0;
821 	int cnt;
822 
823 	dtc = kmalloc(sizeof(struct dmatest_chan), GFP_KERNEL);
824 	if (!dtc) {
825 		pr_warn("No memory for %s\n", dma_chan_name(chan));
826 		return -ENOMEM;
827 	}
828 
829 	dtc->chan = chan;
830 	INIT_LIST_HEAD(&dtc->threads);
831 
832 	if (dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask)) {
833 		if (dmatest == 0) {
834 			cnt = dmatest_add_threads(info, dtc, DMA_MEMCPY);
835 			thread_count += cnt > 0 ? cnt : 0;
836 		}
837 	}
838 
839 	if (dma_has_cap(DMA_SG, dma_dev->cap_mask)) {
840 		if (dmatest == 1) {
841 			cnt = dmatest_add_threads(info, dtc, DMA_SG);
842 			thread_count += cnt > 0 ? cnt : 0;
843 		}
844 	}
845 
846 	if (dma_has_cap(DMA_XOR, dma_dev->cap_mask)) {
847 		cnt = dmatest_add_threads(info, dtc, DMA_XOR);
848 		thread_count += cnt > 0 ? cnt : 0;
849 	}
850 	if (dma_has_cap(DMA_PQ, dma_dev->cap_mask)) {
851 		cnt = dmatest_add_threads(info, dtc, DMA_PQ);
852 		thread_count += cnt > 0 ? cnt : 0;
853 	}
854 
855 	pr_info("Started %u threads using %s\n",
856 		thread_count, dma_chan_name(chan));
857 
858 	list_add_tail(&dtc->node, &info->channels);
859 	info->nr_channels++;
860 
861 	return 0;
862 }
863 
864 static bool filter(struct dma_chan *chan, void *param)
865 {
866 	struct dmatest_params *params = param;
867 
868 	if (!dmatest_match_channel(params, chan) ||
869 	    !dmatest_match_device(params, chan->device))
870 		return false;
871 	else
872 		return true;
873 }
874 
875 static void request_channels(struct dmatest_info *info,
876 			     enum dma_transaction_type type)
877 {
878 	dma_cap_mask_t mask;
879 
880 	dma_cap_zero(mask);
881 	dma_cap_set(type, mask);
882 	for (;;) {
883 		struct dmatest_params *params = &info->params;
884 		struct dma_chan *chan;
885 
886 		chan = dma_request_channel(mask, filter, params);
887 		if (chan) {
888 			if (dmatest_add_channel(info, chan)) {
889 				dma_release_channel(chan);
890 				break; /* add_channel failed, punt */
891 			}
892 		} else
893 			break; /* no more channels available */
894 		if (params->max_channels &&
895 		    info->nr_channels >= params->max_channels)
896 			break; /* we have all we need */
897 	}
898 }
899 
900 static void run_threaded_test(struct dmatest_info *info)
901 {
902 	struct dmatest_params *params = &info->params;
903 
904 	/* Copy test parameters */
905 	params->buf_size = test_buf_size;
906 	strlcpy(params->channel, strim(test_channel), sizeof(params->channel));
907 	strlcpy(params->device, strim(test_device), sizeof(params->device));
908 	params->threads_per_chan = threads_per_chan;
909 	params->max_channels = max_channels;
910 	params->iterations = iterations;
911 	params->xor_sources = xor_sources;
912 	params->pq_sources = pq_sources;
913 	params->timeout = timeout;
914 	params->noverify = noverify;
915 
916 	request_channels(info, DMA_MEMCPY);
917 	request_channels(info, DMA_XOR);
918 	request_channels(info, DMA_SG);
919 	request_channels(info, DMA_PQ);
920 }
921 
922 static void stop_threaded_test(struct dmatest_info *info)
923 {
924 	struct dmatest_chan *dtc, *_dtc;
925 	struct dma_chan *chan;
926 
927 	list_for_each_entry_safe(dtc, _dtc, &info->channels, node) {
928 		list_del(&dtc->node);
929 		chan = dtc->chan;
930 		dmatest_cleanup_channel(dtc);
931 		pr_debug("dropped channel %s\n", dma_chan_name(chan));
932 		dma_release_channel(chan);
933 	}
934 
935 	info->nr_channels = 0;
936 }
937 
938 static void restart_threaded_test(struct dmatest_info *info, bool run)
939 {
940 	/* we might be called early to set run=, defer running until all
941 	 * parameters have been evaluated
942 	 */
943 	if (!info->did_init)
944 		return;
945 
946 	/* Stop any running test first */
947 	stop_threaded_test(info);
948 
949 	/* Run test with new parameters */
950 	run_threaded_test(info);
951 }
952 
953 static int dmatest_run_get(char *val, const struct kernel_param *kp)
954 {
955 	struct dmatest_info *info = &test_info;
956 
957 	mutex_lock(&info->lock);
958 	if (is_threaded_test_run(info)) {
959 		dmatest_run = true;
960 	} else {
961 		stop_threaded_test(info);
962 		dmatest_run = false;
963 	}
964 	mutex_unlock(&info->lock);
965 
966 	return param_get_bool(val, kp);
967 }
968 
969 static int dmatest_run_set(const char *val, const struct kernel_param *kp)
970 {
971 	struct dmatest_info *info = &test_info;
972 	int ret;
973 
974 	mutex_lock(&info->lock);
975 	ret = param_set_bool(val, kp);
976 	if (ret) {
977 		mutex_unlock(&info->lock);
978 		return ret;
979 	}
980 
981 	if (is_threaded_test_run(info))
982 		ret = -EBUSY;
983 	else if (dmatest_run)
984 		restart_threaded_test(info, dmatest_run);
985 
986 	mutex_unlock(&info->lock);
987 
988 	return ret;
989 }
990 
991 static int __init dmatest_init(void)
992 {
993 	struct dmatest_info *info = &test_info;
994 	struct dmatest_params *params = &info->params;
995 
996 	if (dmatest_run) {
997 		mutex_lock(&info->lock);
998 		run_threaded_test(info);
999 		mutex_unlock(&info->lock);
1000 	}
1001 
1002 	if (params->iterations && wait)
1003 		wait_event(thread_wait, !is_threaded_test_run(info));
1004 
1005 	/* module parameters are stable, inittime tests are started,
1006 	 * let userspace take over 'run' control
1007 	 */
1008 	info->did_init = true;
1009 
1010 	return 0;
1011 }
1012 /* when compiled-in wait for drivers to load first */
1013 late_initcall(dmatest_init);
1014 
1015 static void __exit dmatest_exit(void)
1016 {
1017 	struct dmatest_info *info = &test_info;
1018 
1019 	mutex_lock(&info->lock);
1020 	stop_threaded_test(info);
1021 	mutex_unlock(&info->lock);
1022 }
1023 module_exit(dmatest_exit);
1024 
1025 MODULE_AUTHOR("Haavard Skinnemoen (Atmel)");
1026 MODULE_LICENSE("GPL v2");
1027