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v3.15
  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
 25static unsigned int test_buf_size = 16384;
 26module_param(test_buf_size, uint, S_IRUGO | S_IWUSR);
 27MODULE_PARM_DESC(test_buf_size, "Size of the memcpy test buffer");
 28
 29static char test_channel[20];
 30module_param_string(channel, test_channel, sizeof(test_channel),
 31		S_IRUGO | S_IWUSR);
 32MODULE_PARM_DESC(channel, "Bus ID of the channel to test (default: any)");
 33
 34static char test_device[32];
 35module_param_string(device, test_device, sizeof(test_device),
 36		S_IRUGO | S_IWUSR);
 37MODULE_PARM_DESC(device, "Bus ID of the DMA Engine to test (default: any)");
 38
 39static unsigned int threads_per_chan = 1;
 40module_param(threads_per_chan, uint, S_IRUGO | S_IWUSR);
 41MODULE_PARM_DESC(threads_per_chan,
 42		"Number of threads to start per channel (default: 1)");
 43
 44static unsigned int max_channels;
 45module_param(max_channels, uint, S_IRUGO | S_IWUSR);
 46MODULE_PARM_DESC(max_channels,
 47		"Maximum number of channels to use (default: all)");
 48
 49static unsigned int iterations;
 50module_param(iterations, uint, S_IRUGO | S_IWUSR);
 51MODULE_PARM_DESC(iterations,
 52		"Iterations before stopping test (default: infinite)");
 53
 
 
 
 
 
 54static unsigned int xor_sources = 3;
 55module_param(xor_sources, uint, S_IRUGO | S_IWUSR);
 56MODULE_PARM_DESC(xor_sources,
 57		"Number of xor source buffers (default: 3)");
 58
 59static unsigned int pq_sources = 3;
 60module_param(pq_sources, uint, S_IRUGO | S_IWUSR);
 61MODULE_PARM_DESC(pq_sources,
 62		"Number of p+q source buffers (default: 3)");
 63
 64static int timeout = 3000;
 65module_param(timeout, uint, S_IRUGO | S_IWUSR);
 66MODULE_PARM_DESC(timeout, "Transfer Timeout in msec (default: 3000), "
 67		 "Pass -1 for infinite timeout");
 68
 69static bool noverify;
 70module_param(noverify, bool, S_IRUGO | S_IWUSR);
 71MODULE_PARM_DESC(noverify, "Disable random data setup and verification");
 
 
 
 
 72
 73static bool verbose;
 74module_param(verbose, bool, S_IRUGO | S_IWUSR);
 75MODULE_PARM_DESC(verbose, "Enable \"success\" result messages (default: off)");
 76
 77/**
 78 * struct dmatest_params - test parameters.
 79 * @buf_size:		size of the memcpy test buffer
 80 * @channel:		bus ID of the channel to test
 81 * @device:		bus ID of the DMA Engine to test
 82 * @threads_per_chan:	number of threads to start per channel
 83 * @max_channels:	maximum number of channels to use
 84 * @iterations:		iterations before stopping test
 85 * @xor_sources:	number of xor source buffers
 86 * @pq_sources:		number of p+q source buffers
 87 * @timeout:		transfer timeout in msec, -1 for infinite timeout
 88 */
 89struct dmatest_params {
 90	unsigned int	buf_size;
 91	char		channel[20];
 92	char		device[32];
 93	unsigned int	threads_per_chan;
 94	unsigned int	max_channels;
 95	unsigned int	iterations;
 96	unsigned int	xor_sources;
 97	unsigned int	pq_sources;
 98	int		timeout;
 99	bool		noverify;
 
100};
101
102/**
103 * struct dmatest_info - test information.
104 * @params:		test parameters
105 * @lock:		access protection to the fields of this structure
106 */
107static struct dmatest_info {
108	/* Test parameters */
109	struct dmatest_params	params;
110
111	/* Internal state */
112	struct list_head	channels;
113	unsigned int		nr_channels;
114	struct mutex		lock;
115	bool			did_init;
116} test_info = {
117	.channels = LIST_HEAD_INIT(test_info.channels),
118	.lock = __MUTEX_INITIALIZER(test_info.lock),
119};
120
121static int dmatest_run_set(const char *val, const struct kernel_param *kp);
122static int dmatest_run_get(char *val, const struct kernel_param *kp);
123static struct kernel_param_ops run_ops = {
124	.set = dmatest_run_set,
125	.get = dmatest_run_get,
126};
127static bool dmatest_run;
128module_param_cb(run, &run_ops, &dmatest_run, S_IRUGO | S_IWUSR);
129MODULE_PARM_DESC(run, "Run the test (default: false)");
130
131/* Maximum amount of mismatched bytes in buffer to print */
132#define MAX_ERROR_COUNT		32
133
134/*
135 * Initialization patterns. All bytes in the source buffer has bit 7
136 * set, all bytes in the destination buffer has bit 7 cleared.
137 *
138 * Bit 6 is set for all bytes which are to be copied by the DMA
139 * engine. Bit 5 is set for all bytes which are to be overwritten by
140 * the DMA engine.
141 *
142 * The remaining bits are the inverse of a counter which increments by
143 * one for each byte address.
144 */
145#define PATTERN_SRC		0x80
146#define PATTERN_DST		0x00
147#define PATTERN_COPY		0x40
148#define PATTERN_OVERWRITE	0x20
149#define PATTERN_COUNT_MASK	0x1f
 
 
 
 
 
 
 
150
151struct dmatest_thread {
152	struct list_head	node;
153	struct dmatest_info	*info;
154	struct task_struct	*task;
155	struct dma_chan		*chan;
156	u8			**srcs;
 
157	u8			**dsts;
 
158	enum dma_transaction_type type;
 
 
159	bool			done;
160};
161
162struct dmatest_chan {
163	struct list_head	node;
164	struct dma_chan		*chan;
165	struct list_head	threads;
166};
167
168static DECLARE_WAIT_QUEUE_HEAD(thread_wait);
169static bool wait;
170
171static bool is_threaded_test_run(struct dmatest_info *info)
172{
173	struct dmatest_chan *dtc;
174
175	list_for_each_entry(dtc, &info->channels, node) {
176		struct dmatest_thread *thread;
177
178		list_for_each_entry(thread, &dtc->threads, node) {
179			if (!thread->done)
180				return true;
181		}
182	}
183
184	return false;
185}
186
187static int dmatest_wait_get(char *val, const struct kernel_param *kp)
188{
189	struct dmatest_info *info = &test_info;
190	struct dmatest_params *params = &info->params;
191
192	if (params->iterations)
193		wait_event(thread_wait, !is_threaded_test_run(info));
194	wait = true;
195	return param_get_bool(val, kp);
196}
197
198static struct kernel_param_ops wait_ops = {
199	.get = dmatest_wait_get,
200	.set = param_set_bool,
201};
202module_param_cb(wait, &wait_ops, &wait, S_IRUGO);
203MODULE_PARM_DESC(wait, "Wait for tests to complete (default: false)");
204
205static bool dmatest_match_channel(struct dmatest_params *params,
206		struct dma_chan *chan)
207{
208	if (params->channel[0] == '\0')
209		return true;
210	return strcmp(dma_chan_name(chan), params->channel) == 0;
211}
212
213static bool dmatest_match_device(struct dmatest_params *params,
214		struct dma_device *device)
215{
216	if (params->device[0] == '\0')
217		return true;
218	return strcmp(dev_name(device->dev), params->device) == 0;
219}
220
221static unsigned long dmatest_random(void)
222{
223	unsigned long buf;
224
225	prandom_bytes(&buf, sizeof(buf));
226	return buf;
227}
228
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
229static void dmatest_init_srcs(u8 **bufs, unsigned int start, unsigned int len,
230		unsigned int buf_size)
231{
232	unsigned int i;
233	u8 *buf;
234
235	for (; (buf = *bufs); bufs++) {
236		for (i = 0; i < start; i++)
237			buf[i] = PATTERN_SRC | (~i & PATTERN_COUNT_MASK);
238		for ( ; i < start + len; i++)
239			buf[i] = PATTERN_SRC | PATTERN_COPY
240				| (~i & PATTERN_COUNT_MASK);
241		for ( ; i < buf_size; i++)
242			buf[i] = PATTERN_SRC | (~i & PATTERN_COUNT_MASK);
243		buf++;
244	}
245}
246
247static void dmatest_init_dsts(u8 **bufs, unsigned int start, unsigned int len,
248		unsigned int buf_size)
249{
250	unsigned int i;
251	u8 *buf;
252
253	for (; (buf = *bufs); bufs++) {
254		for (i = 0; i < start; i++)
255			buf[i] = PATTERN_DST | (~i & PATTERN_COUNT_MASK);
256		for ( ; i < start + len; i++)
257			buf[i] = PATTERN_DST | PATTERN_OVERWRITE
258				| (~i & PATTERN_COUNT_MASK);
259		for ( ; i < buf_size; i++)
260			buf[i] = PATTERN_DST | (~i & PATTERN_COUNT_MASK);
261	}
262}
263
264static void dmatest_mismatch(u8 actual, u8 pattern, unsigned int index,
265		unsigned int counter, bool is_srcbuf)
266{
267	u8		diff = actual ^ pattern;
268	u8		expected = pattern | (~counter & PATTERN_COUNT_MASK);
269	const char	*thread_name = current->comm;
270
271	if (is_srcbuf)
272		pr_warn("%s: srcbuf[0x%x] overwritten! Expected %02x, got %02x\n",
273			thread_name, index, expected, actual);
274	else if ((pattern & PATTERN_COPY)
275			&& (diff & (PATTERN_COPY | PATTERN_OVERWRITE)))
276		pr_warn("%s: dstbuf[0x%x] not copied! Expected %02x, got %02x\n",
277			thread_name, index, expected, actual);
278	else if (diff & PATTERN_SRC)
279		pr_warn("%s: dstbuf[0x%x] was copied! Expected %02x, got %02x\n",
280			thread_name, index, expected, actual);
281	else
282		pr_warn("%s: dstbuf[0x%x] mismatch! Expected %02x, got %02x\n",
283			thread_name, index, expected, actual);
284}
285
286static unsigned int dmatest_verify(u8 **bufs, unsigned int start,
287		unsigned int end, unsigned int counter, u8 pattern,
288		bool is_srcbuf)
289{
290	unsigned int i;
291	unsigned int error_count = 0;
292	u8 actual;
293	u8 expected;
294	u8 *buf;
295	unsigned int counter_orig = counter;
296
297	for (; (buf = *bufs); bufs++) {
298		counter = counter_orig;
299		for (i = start; i < end; i++) {
300			actual = buf[i];
301			expected = pattern | (~counter & PATTERN_COUNT_MASK);
302			if (actual != expected) {
303				if (error_count < MAX_ERROR_COUNT)
304					dmatest_mismatch(actual, pattern, i,
305							 counter, is_srcbuf);
 
306				error_count++;
307			}
308			counter++;
309		}
310	}
311
312	if (error_count > MAX_ERROR_COUNT)
313		pr_warn("%s: %u errors suppressed\n",
314			current->comm, error_count - MAX_ERROR_COUNT);
315
316	return error_count;
317}
318
319/* poor man's completion - we want to use wait_event_freezable() on it */
320struct dmatest_done {
321	bool			done;
322	wait_queue_head_t	*wait;
323};
324
325static void dmatest_callback(void *arg)
326{
327	struct dmatest_done *done = arg;
328
329	done->done = true;
330	wake_up_all(done->wait);
 
 
 
 
 
 
 
 
 
 
 
 
331}
332
333static unsigned int min_odd(unsigned int x, unsigned int y)
334{
335	unsigned int val = min(x, y);
336
337	return val % 2 ? val : val - 1;
338}
339
340static void result(const char *err, unsigned int n, unsigned int src_off,
341		   unsigned int dst_off, unsigned int len, unsigned long data)
342{
343	pr_info("%s: result #%u: '%s' with src_off=0x%x dst_off=0x%x len=0x%x (%lu)\n",
344		current->comm, n, err, src_off, dst_off, len, data);
345}
346
347static void dbg_result(const char *err, unsigned int n, unsigned int src_off,
348		       unsigned int dst_off, unsigned int len,
349		       unsigned long data)
350{
351	pr_debug("%s: result #%u: '%s' with src_off=0x%x dst_off=0x%x len=0x%x (%lu)\n",
352		   current->comm, n, err, src_off, dst_off, len, data);
353}
354
355#define verbose_result(err, n, src_off, dst_off, len, data) ({ \
356	if (verbose) \
357		result(err, n, src_off, dst_off, len, data); \
358	else \
359		dbg_result(err, n, src_off, dst_off, len, data); \
360})
361
362static unsigned long long dmatest_persec(s64 runtime, unsigned int val)
363{
364	unsigned long long per_sec = 1000000;
365
366	if (runtime <= 0)
367		return 0;
368
369	/* drop precision until runtime is 32-bits */
370	while (runtime > UINT_MAX) {
371		runtime >>= 1;
372		per_sec <<= 1;
373	}
374
375	per_sec *= val;
376	do_div(per_sec, runtime);
377	return per_sec;
378}
379
380static unsigned long long dmatest_KBs(s64 runtime, unsigned long long len)
381{
382	return dmatest_persec(runtime, len >> 10);
383}
384
385/*
386 * This function repeatedly tests DMA transfers of various lengths and
387 * offsets for a given operation type until it is told to exit by
388 * kthread_stop(). There may be multiple threads running this function
389 * in parallel for a single channel, and there may be multiple channels
390 * being tested in parallel.
391 *
392 * Before each test, the source and destination buffer is initialized
393 * with a known pattern. This pattern is different depending on
394 * whether it's in an area which is supposed to be copied or
395 * overwritten, and different in the source and destination buffers.
396 * So if the DMA engine doesn't copy exactly what we tell it to copy,
397 * we'll notice.
398 */
399static int dmatest_func(void *data)
400{
401	DECLARE_WAIT_QUEUE_HEAD_ONSTACK(done_wait);
402	struct dmatest_thread	*thread = data;
403	struct dmatest_done	done = { .wait = &done_wait };
404	struct dmatest_info	*info;
405	struct dmatest_params	*params;
406	struct dma_chan		*chan;
407	struct dma_device	*dev;
408	unsigned int		src_off, dst_off, len;
409	unsigned int		error_count;
410	unsigned int		failed_tests = 0;
411	unsigned int		total_tests = 0;
412	dma_cookie_t		cookie;
413	enum dma_status		status;
414	enum dma_ctrl_flags 	flags;
415	u8			*pq_coefs = NULL;
416	int			ret;
417	int			src_cnt;
418	int			dst_cnt;
419	int			i;
420	ktime_t			ktime;
 
 
421	s64			runtime = 0;
422	unsigned long long	total_len = 0;
 
 
423
424	set_freezable();
425
426	ret = -ENOMEM;
427
428	smp_rmb();
429	info = thread->info;
430	params = &info->params;
431	chan = thread->chan;
432	dev = chan->device;
433	if (thread->type == DMA_MEMCPY)
 
 
 
 
434		src_cnt = dst_cnt = 1;
435	else if (thread->type == DMA_XOR) {
 
436		/* force odd to ensure dst = src */
437		src_cnt = min_odd(params->xor_sources | 1, dev->max_xor);
438		dst_cnt = 1;
 
439	} else if (thread->type == DMA_PQ) {
440		/* force odd to ensure dst = src */
441		src_cnt = min_odd(params->pq_sources | 1, dma_maxpq(dev, 0));
442		dst_cnt = 2;
 
443
444		pq_coefs = kmalloc(params->pq_sources+1, GFP_KERNEL);
445		if (!pq_coefs)
446			goto err_thread_type;
447
448		for (i = 0; i < src_cnt; i++)
449			pq_coefs[i] = 1;
450	} else
451		goto err_thread_type;
452
453	thread->srcs = kcalloc(src_cnt+1, sizeof(u8 *), GFP_KERNEL);
454	if (!thread->srcs)
455		goto err_srcs;
 
 
 
 
 
456	for (i = 0; i < src_cnt; i++) {
457		thread->srcs[i] = kmalloc(params->buf_size, GFP_KERNEL);
458		if (!thread->srcs[i])
 
459			goto err_srcbuf;
 
 
 
 
 
 
460	}
461	thread->srcs[i] = NULL;
462
463	thread->dsts = kcalloc(dst_cnt+1, sizeof(u8 *), GFP_KERNEL);
464	if (!thread->dsts)
465		goto err_dsts;
 
 
 
 
 
466	for (i = 0; i < dst_cnt; i++) {
467		thread->dsts[i] = kmalloc(params->buf_size, GFP_KERNEL);
468		if (!thread->dsts[i])
 
469			goto err_dstbuf;
 
 
 
 
 
 
470	}
471	thread->dsts[i] = NULL;
472
473	set_user_nice(current, 10);
474
475	/*
476	 * src and dst buffers are freed by ourselves below
477	 */
478	flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
479
480	ktime = ktime_get();
481	while (!kthread_should_stop()
482	       && !(params->iterations && total_tests >= params->iterations)) {
483		struct dma_async_tx_descriptor *tx = NULL;
484		struct dmaengine_unmap_data *um;
485		dma_addr_t srcs[src_cnt];
486		dma_addr_t *dsts;
487		u8 align = 0;
488
489		total_tests++;
490
491		/* honor alignment restrictions */
492		if (thread->type == DMA_MEMCPY)
493			align = dev->copy_align;
494		else if (thread->type == DMA_XOR)
495			align = dev->xor_align;
496		else if (thread->type == DMA_PQ)
497			align = dev->pq_align;
498
499		if (1 << align > params->buf_size) {
500			pr_err("%u-byte buffer too small for %d-byte alignment\n",
501			       params->buf_size, 1 << align);
502			break;
503		}
504
505		if (params->noverify) {
506			len = params->buf_size;
 
 
 
 
 
 
 
 
 
 
507			src_off = 0;
508			dst_off = 0;
509		} else {
510			len = dmatest_random() % params->buf_size + 1;
511			len = (len >> align) << align;
512			if (!len)
513				len = 1 << align;
514			src_off = dmatest_random() % (params->buf_size - len + 1);
515			dst_off = dmatest_random() % (params->buf_size - len + 1);
516
517			src_off = (src_off >> align) << align;
518			dst_off = (dst_off >> align) << align;
 
519
 
 
520			dmatest_init_srcs(thread->srcs, src_off, len,
521					  params->buf_size);
522			dmatest_init_dsts(thread->dsts, dst_off, len,
523					  params->buf_size);
524		}
525
526		len = (len >> align) << align;
527		if (!len)
528			len = 1 << align;
529		total_len += len;
530
531		um = dmaengine_get_unmap_data(dev->dev, src_cnt+dst_cnt,
532					      GFP_KERNEL);
533		if (!um) {
534			failed_tests++;
535			result("unmap data NULL", total_tests,
536			       src_off, dst_off, len, ret);
537			continue;
538		}
539
540		um->len = params->buf_size;
541		for (i = 0; i < src_cnt; i++) {
542			void *buf = thread->srcs[i];
543			struct page *pg = virt_to_page(buf);
544			unsigned pg_off = (unsigned long) buf & ~PAGE_MASK;
545
546			um->addr[i] = dma_map_page(dev->dev, pg, pg_off,
547						   um->len, DMA_TO_DEVICE);
548			srcs[i] = um->addr[i] + src_off;
549			ret = dma_mapping_error(dev->dev, um->addr[i]);
550			if (ret) {
551				dmaengine_unmap_put(um);
552				result("src mapping error", total_tests,
553				       src_off, dst_off, len, ret);
554				failed_tests++;
555				continue;
556			}
557			um->to_cnt++;
558		}
559		/* map with DMA_BIDIRECTIONAL to force writeback/invalidate */
560		dsts = &um->addr[src_cnt];
561		for (i = 0; i < dst_cnt; i++) {
562			void *buf = thread->dsts[i];
563			struct page *pg = virt_to_page(buf);
564			unsigned pg_off = (unsigned long) buf & ~PAGE_MASK;
565
566			dsts[i] = dma_map_page(dev->dev, pg, pg_off, um->len,
567					       DMA_BIDIRECTIONAL);
568			ret = dma_mapping_error(dev->dev, dsts[i]);
569			if (ret) {
570				dmaengine_unmap_put(um);
571				result("dst mapping error", total_tests,
572				       src_off, dst_off, len, ret);
573				failed_tests++;
574				continue;
575			}
576			um->bidi_cnt++;
577		}
578
579		if (thread->type == DMA_MEMCPY)
580			tx = dev->device_prep_dma_memcpy(chan,
581							 dsts[0] + dst_off,
582							 srcs[0], len, flags);
 
 
 
 
 
583		else if (thread->type == DMA_XOR)
584			tx = dev->device_prep_dma_xor(chan,
585						      dsts[0] + dst_off,
586						      srcs, src_cnt,
587						      len, flags);
588		else if (thread->type == DMA_PQ) {
589			dma_addr_t dma_pq[dst_cnt];
590
591			for (i = 0; i < dst_cnt; i++)
592				dma_pq[i] = dsts[i] + dst_off;
593			tx = dev->device_prep_dma_pq(chan, dma_pq, srcs,
594						     src_cnt, pq_coefs,
595						     len, flags);
596		}
597
598		if (!tx) {
599			dmaengine_unmap_put(um);
600			result("prep error", total_tests, src_off,
601			       dst_off, len, ret);
602			msleep(100);
603			failed_tests++;
604			continue;
605		}
606
607		done.done = false;
608		tx->callback = dmatest_callback;
609		tx->callback_param = &done;
610		cookie = tx->tx_submit(tx);
611
612		if (dma_submit_error(cookie)) {
613			dmaengine_unmap_put(um);
614			result("submit error", total_tests, src_off,
615			       dst_off, len, ret);
616			msleep(100);
617			failed_tests++;
618			continue;
619		}
620		dma_async_issue_pending(chan);
621
622		wait_event_freezable_timeout(done_wait, done.done,
623					     msecs_to_jiffies(params->timeout));
624
625		status = dma_async_is_tx_complete(chan, cookie, NULL, NULL);
626
627		if (!done.done) {
628			/*
629			 * We're leaving the timed out dma operation with
630			 * dangling pointer to done_wait.  To make this
631			 * correct, we'll need to allocate wait_done for
632			 * each test iteration and perform "who's gonna
633			 * free it this time?" dancing.  For now, just
634			 * leave it dangling.
635			 */
636			dmaengine_unmap_put(um);
637			result("test timed out", total_tests, src_off, dst_off,
638			       len, 0);
639			failed_tests++;
640			continue;
641		} else if (status != DMA_COMPLETE) {
642			dmaengine_unmap_put(um);
643			result(status == DMA_ERROR ?
644			       "completion error status" :
645			       "completion busy status", total_tests, src_off,
646			       dst_off, len, ret);
647			failed_tests++;
648			continue;
649		}
650
651		dmaengine_unmap_put(um);
652
653		if (params->noverify) {
654			verbose_result("test passed", total_tests, src_off,
655				       dst_off, len, 0);
656			continue;
657		}
658
 
659		pr_debug("%s: verifying source buffer...\n", current->comm);
660		error_count = dmatest_verify(thread->srcs, 0, src_off,
661				0, PATTERN_SRC, true);
662		error_count += dmatest_verify(thread->srcs, src_off,
663				src_off + len, src_off,
664				PATTERN_SRC | PATTERN_COPY, true);
665		error_count += dmatest_verify(thread->srcs, src_off + len,
666				params->buf_size, src_off + len,
667				PATTERN_SRC, true);
668
669		pr_debug("%s: verifying dest buffer...\n", current->comm);
670		error_count += dmatest_verify(thread->dsts, 0, dst_off,
671				0, PATTERN_DST, false);
 
672		error_count += dmatest_verify(thread->dsts, dst_off,
673				dst_off + len, src_off,
674				PATTERN_SRC | PATTERN_COPY, false);
 
675		error_count += dmatest_verify(thread->dsts, dst_off + len,
676				params->buf_size, dst_off + len,
677				PATTERN_DST, false);
 
 
 
678
679		if (error_count) {
680			result("data error", total_tests, src_off, dst_off,
681			       len, error_count);
682			failed_tests++;
683		} else {
684			verbose_result("test passed", total_tests, src_off,
685				       dst_off, len, 0);
686		}
687	}
688	runtime = ktime_us_delta(ktime_get(), ktime);
 
 
 
689
690	ret = 0;
691	for (i = 0; thread->dsts[i]; i++)
692		kfree(thread->dsts[i]);
693err_dstbuf:
 
 
 
 
694	kfree(thread->dsts);
695err_dsts:
696	for (i = 0; thread->srcs[i]; i++)
697		kfree(thread->srcs[i]);
698err_srcbuf:
 
 
 
 
699	kfree(thread->srcs);
700err_srcs:
701	kfree(pq_coefs);
702err_thread_type:
703	pr_info("%s: summary %u tests, %u failures %llu iops %llu KB/s (%d)\n",
704		current->comm, total_tests, failed_tests,
705		dmatest_persec(runtime, total_tests),
706		dmatest_KBs(runtime, total_len), ret);
707
708	/* terminate all transfers on specified channels */
709	if (ret)
710		dmaengine_terminate_all(chan);
711
712	thread->done = true;
713	wake_up(&thread_wait);
714
715	return ret;
716}
717
718static void dmatest_cleanup_channel(struct dmatest_chan *dtc)
719{
720	struct dmatest_thread	*thread;
721	struct dmatest_thread	*_thread;
722	int			ret;
723
724	list_for_each_entry_safe(thread, _thread, &dtc->threads, node) {
725		ret = kthread_stop(thread->task);
726		pr_debug("thread %s exited with status %d\n",
727			 thread->task->comm, ret);
728		list_del(&thread->node);
729		put_task_struct(thread->task);
730		kfree(thread);
731	}
732
733	/* terminate all transfers on specified channels */
734	dmaengine_terminate_all(dtc->chan);
735
736	kfree(dtc);
737}
738
739static int dmatest_add_threads(struct dmatest_info *info,
740		struct dmatest_chan *dtc, enum dma_transaction_type type)
741{
742	struct dmatest_params *params = &info->params;
743	struct dmatest_thread *thread;
744	struct dma_chan *chan = dtc->chan;
745	char *op;
746	unsigned int i;
747
748	if (type == DMA_MEMCPY)
749		op = "copy";
 
 
750	else if (type == DMA_XOR)
751		op = "xor";
752	else if (type == DMA_PQ)
753		op = "pq";
754	else
755		return -EINVAL;
756
757	for (i = 0; i < params->threads_per_chan; i++) {
758		thread = kzalloc(sizeof(struct dmatest_thread), GFP_KERNEL);
759		if (!thread) {
760			pr_warn("No memory for %s-%s%u\n",
761				dma_chan_name(chan), op, i);
762			break;
763		}
764		thread->info = info;
765		thread->chan = dtc->chan;
766		thread->type = type;
 
 
767		smp_wmb();
768		thread->task = kthread_create(dmatest_func, thread, "%s-%s%u",
769				dma_chan_name(chan), op, i);
770		if (IS_ERR(thread->task)) {
771			pr_warn("Failed to create thread %s-%s%u\n",
772				dma_chan_name(chan), op, i);
773			kfree(thread);
774			break;
775		}
776
777		/* srcbuf and dstbuf are allocated by the thread itself */
778		get_task_struct(thread->task);
779		list_add_tail(&thread->node, &dtc->threads);
780		wake_up_process(thread->task);
781	}
782
783	return i;
784}
785
786static int dmatest_add_channel(struct dmatest_info *info,
787		struct dma_chan *chan)
788{
789	struct dmatest_chan	*dtc;
790	struct dma_device	*dma_dev = chan->device;
791	unsigned int		thread_count = 0;
792	int cnt;
793
794	dtc = kmalloc(sizeof(struct dmatest_chan), GFP_KERNEL);
795	if (!dtc) {
796		pr_warn("No memory for %s\n", dma_chan_name(chan));
797		return -ENOMEM;
798	}
799
800	dtc->chan = chan;
801	INIT_LIST_HEAD(&dtc->threads);
802
803	if (dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask)) {
804		cnt = dmatest_add_threads(info, dtc, DMA_MEMCPY);
805		thread_count += cnt > 0 ? cnt : 0;
 
 
806	}
 
 
 
 
 
 
 
 
807	if (dma_has_cap(DMA_XOR, dma_dev->cap_mask)) {
808		cnt = dmatest_add_threads(info, dtc, DMA_XOR);
809		thread_count += cnt > 0 ? cnt : 0;
810	}
811	if (dma_has_cap(DMA_PQ, dma_dev->cap_mask)) {
812		cnt = dmatest_add_threads(info, dtc, DMA_PQ);
813		thread_count += cnt > 0 ? cnt : 0;
814	}
815
816	pr_info("Started %u threads using %s\n",
817		thread_count, dma_chan_name(chan));
818
819	list_add_tail(&dtc->node, &info->channels);
820	info->nr_channels++;
821
822	return 0;
823}
824
825static bool filter(struct dma_chan *chan, void *param)
826{
827	struct dmatest_params *params = param;
828
829	if (!dmatest_match_channel(params, chan) ||
830	    !dmatest_match_device(params, chan->device))
831		return false;
832	else
833		return true;
834}
835
836static void request_channels(struct dmatest_info *info,
837			     enum dma_transaction_type type)
838{
839	dma_cap_mask_t mask;
840
841	dma_cap_zero(mask);
842	dma_cap_set(type, mask);
843	for (;;) {
844		struct dmatest_params *params = &info->params;
845		struct dma_chan *chan;
846
847		chan = dma_request_channel(mask, filter, params);
848		if (chan) {
849			if (dmatest_add_channel(info, chan)) {
850				dma_release_channel(chan);
851				break; /* add_channel failed, punt */
852			}
853		} else
854			break; /* no more channels available */
855		if (params->max_channels &&
856		    info->nr_channels >= params->max_channels)
857			break; /* we have all we need */
858	}
859}
860
861static void run_threaded_test(struct dmatest_info *info)
862{
863	struct dmatest_params *params = &info->params;
864
865	/* Copy test parameters */
866	params->buf_size = test_buf_size;
867	strlcpy(params->channel, strim(test_channel), sizeof(params->channel));
868	strlcpy(params->device, strim(test_device), sizeof(params->device));
869	params->threads_per_chan = threads_per_chan;
870	params->max_channels = max_channels;
871	params->iterations = iterations;
872	params->xor_sources = xor_sources;
873	params->pq_sources = pq_sources;
874	params->timeout = timeout;
875	params->noverify = noverify;
 
876
877	request_channels(info, DMA_MEMCPY);
 
878	request_channels(info, DMA_XOR);
879	request_channels(info, DMA_PQ);
880}
881
882static void stop_threaded_test(struct dmatest_info *info)
883{
884	struct dmatest_chan *dtc, *_dtc;
885	struct dma_chan *chan;
886
887	list_for_each_entry_safe(dtc, _dtc, &info->channels, node) {
888		list_del(&dtc->node);
889		chan = dtc->chan;
890		dmatest_cleanup_channel(dtc);
891		pr_debug("dropped channel %s\n", dma_chan_name(chan));
892		dma_release_channel(chan);
893	}
894
895	info->nr_channels = 0;
896}
897
898static void restart_threaded_test(struct dmatest_info *info, bool run)
899{
900	/* we might be called early to set run=, defer running until all
901	 * parameters have been evaluated
902	 */
903	if (!info->did_init)
904		return;
905
906	/* Stop any running test first */
907	stop_threaded_test(info);
908
909	/* Run test with new parameters */
910	run_threaded_test(info);
911}
912
913static int dmatest_run_get(char *val, const struct kernel_param *kp)
914{
915	struct dmatest_info *info = &test_info;
916
917	mutex_lock(&info->lock);
918	if (is_threaded_test_run(info)) {
919		dmatest_run = true;
920	} else {
921		stop_threaded_test(info);
922		dmatest_run = false;
923	}
924	mutex_unlock(&info->lock);
925
926	return param_get_bool(val, kp);
927}
928
929static int dmatest_run_set(const char *val, const struct kernel_param *kp)
930{
931	struct dmatest_info *info = &test_info;
932	int ret;
933
934	mutex_lock(&info->lock);
935	ret = param_set_bool(val, kp);
936	if (ret) {
937		mutex_unlock(&info->lock);
938		return ret;
939	}
940
941	if (is_threaded_test_run(info))
942		ret = -EBUSY;
943	else if (dmatest_run)
944		restart_threaded_test(info, dmatest_run);
945
946	mutex_unlock(&info->lock);
947
948	return ret;
949}
950
951static int __init dmatest_init(void)
952{
953	struct dmatest_info *info = &test_info;
954	struct dmatest_params *params = &info->params;
955
956	if (dmatest_run) {
957		mutex_lock(&info->lock);
958		run_threaded_test(info);
959		mutex_unlock(&info->lock);
960	}
961
962	if (params->iterations && wait)
963		wait_event(thread_wait, !is_threaded_test_run(info));
964
965	/* module parameters are stable, inittime tests are started,
966	 * let userspace take over 'run' control
967	 */
968	info->did_init = true;
969
970	return 0;
971}
972/* when compiled-in wait for drivers to load first */
973late_initcall(dmatest_init);
974
975static void __exit dmatest_exit(void)
976{
977	struct dmatest_info *info = &test_info;
978
979	mutex_lock(&info->lock);
980	stop_threaded_test(info);
981	mutex_unlock(&info->lock);
982}
983module_exit(dmatest_exit);
984
985MODULE_AUTHOR("Haavard Skinnemoen (Atmel)");
986MODULE_LICENSE("GPL v2");
v4.17
   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/sched/task.h>
  20#include <linux/module.h>
  21#include <linux/moduleparam.h>
  22#include <linux/random.h>
  23#include <linux/slab.h>
  24#include <linux/wait.h>
  25
  26static unsigned int test_buf_size = 16384;
  27module_param(test_buf_size, uint, S_IRUGO | S_IWUSR);
  28MODULE_PARM_DESC(test_buf_size, "Size of the memcpy test buffer");
  29
  30static char test_channel[20];
  31module_param_string(channel, test_channel, sizeof(test_channel),
  32		S_IRUGO | S_IWUSR);
  33MODULE_PARM_DESC(channel, "Bus ID of the channel to test (default: any)");
  34
  35static char test_device[32];
  36module_param_string(device, test_device, sizeof(test_device),
  37		S_IRUGO | S_IWUSR);
  38MODULE_PARM_DESC(device, "Bus ID of the DMA Engine to test (default: any)");
  39
  40static unsigned int threads_per_chan = 1;
  41module_param(threads_per_chan, uint, S_IRUGO | S_IWUSR);
  42MODULE_PARM_DESC(threads_per_chan,
  43		"Number of threads to start per channel (default: 1)");
  44
  45static unsigned int max_channels;
  46module_param(max_channels, uint, S_IRUGO | S_IWUSR);
  47MODULE_PARM_DESC(max_channels,
  48		"Maximum number of channels to use (default: all)");
  49
  50static unsigned int iterations;
  51module_param(iterations, uint, S_IRUGO | S_IWUSR);
  52MODULE_PARM_DESC(iterations,
  53		"Iterations before stopping test (default: infinite)");
  54
  55static unsigned int dmatest;
  56module_param(dmatest, uint, S_IRUGO | S_IWUSR);
  57MODULE_PARM_DESC(dmatest,
  58		"dmatest 0-memcpy 1-memset (default: 0)");
  59
  60static unsigned int xor_sources = 3;
  61module_param(xor_sources, uint, S_IRUGO | S_IWUSR);
  62MODULE_PARM_DESC(xor_sources,
  63		"Number of xor source buffers (default: 3)");
  64
  65static unsigned int pq_sources = 3;
  66module_param(pq_sources, uint, S_IRUGO | S_IWUSR);
  67MODULE_PARM_DESC(pq_sources,
  68		"Number of p+q source buffers (default: 3)");
  69
  70static int timeout = 3000;
  71module_param(timeout, uint, S_IRUGO | S_IWUSR);
  72MODULE_PARM_DESC(timeout, "Transfer Timeout in msec (default: 3000), "
  73		 "Pass -1 for infinite timeout");
  74
  75static bool noverify;
  76module_param(noverify, bool, S_IRUGO | S_IWUSR);
  77MODULE_PARM_DESC(noverify, "Disable data verification (default: verify)");
  78
  79static bool norandom;
  80module_param(norandom, bool, 0644);
  81MODULE_PARM_DESC(norandom, "Disable random offset setup (default: random)");
  82
  83static bool verbose;
  84module_param(verbose, bool, S_IRUGO | S_IWUSR);
  85MODULE_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 */
  99struct 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	bool		norandom;
 111};
 112
 113/**
 114 * struct dmatest_info - test information.
 115 * @params:		test parameters
 116 * @lock:		access protection to the fields of this structure
 117 */
 118static struct dmatest_info {
 119	/* Test parameters */
 120	struct dmatest_params	params;
 121
 122	/* Internal state */
 123	struct list_head	channels;
 124	unsigned int		nr_channels;
 125	struct mutex		lock;
 126	bool			did_init;
 127} test_info = {
 128	.channels = LIST_HEAD_INIT(test_info.channels),
 129	.lock = __MUTEX_INITIALIZER(test_info.lock),
 130};
 131
 132static int dmatest_run_set(const char *val, const struct kernel_param *kp);
 133static int dmatest_run_get(char *val, const struct kernel_param *kp);
 134static const struct kernel_param_ops run_ops = {
 135	.set = dmatest_run_set,
 136	.get = dmatest_run_get,
 137};
 138static bool dmatest_run;
 139module_param_cb(run, &run_ops, &dmatest_run, S_IRUGO | S_IWUSR);
 140MODULE_PARM_DESC(run, "Run the test (default: false)");
 141
 142/* Maximum amount of mismatched bytes in buffer to print */
 143#define MAX_ERROR_COUNT		32
 144
 145/*
 146 * Initialization patterns. All bytes in the source buffer has bit 7
 147 * set, all bytes in the destination buffer has bit 7 cleared.
 148 *
 149 * Bit 6 is set for all bytes which are to be copied by the DMA
 150 * engine. Bit 5 is set for all bytes which are to be overwritten by
 151 * the DMA engine.
 152 *
 153 * The remaining bits are the inverse of a counter which increments by
 154 * one for each byte address.
 155 */
 156#define PATTERN_SRC		0x80
 157#define PATTERN_DST		0x00
 158#define PATTERN_COPY		0x40
 159#define PATTERN_OVERWRITE	0x20
 160#define PATTERN_COUNT_MASK	0x1f
 161#define PATTERN_MEMSET_IDX	0x01
 162
 163/* poor man's completion - we want to use wait_event_freezable() on it */
 164struct dmatest_done {
 165	bool			done;
 166	wait_queue_head_t	*wait;
 167};
 168
 169struct dmatest_thread {
 170	struct list_head	node;
 171	struct dmatest_info	*info;
 172	struct task_struct	*task;
 173	struct dma_chan		*chan;
 174	u8			**srcs;
 175	u8			**usrcs;
 176	u8			**dsts;
 177	u8			**udsts;
 178	enum dma_transaction_type type;
 179	wait_queue_head_t done_wait;
 180	struct dmatest_done test_done;
 181	bool			done;
 182};
 183
 184struct dmatest_chan {
 185	struct list_head	node;
 186	struct dma_chan		*chan;
 187	struct list_head	threads;
 188};
 189
 190static DECLARE_WAIT_QUEUE_HEAD(thread_wait);
 191static bool wait;
 192
 193static bool is_threaded_test_run(struct dmatest_info *info)
 194{
 195	struct dmatest_chan *dtc;
 196
 197	list_for_each_entry(dtc, &info->channels, node) {
 198		struct dmatest_thread *thread;
 199
 200		list_for_each_entry(thread, &dtc->threads, node) {
 201			if (!thread->done)
 202				return true;
 203		}
 204	}
 205
 206	return false;
 207}
 208
 209static int dmatest_wait_get(char *val, const struct kernel_param *kp)
 210{
 211	struct dmatest_info *info = &test_info;
 212	struct dmatest_params *params = &info->params;
 213
 214	if (params->iterations)
 215		wait_event(thread_wait, !is_threaded_test_run(info));
 216	wait = true;
 217	return param_get_bool(val, kp);
 218}
 219
 220static const struct kernel_param_ops wait_ops = {
 221	.get = dmatest_wait_get,
 222	.set = param_set_bool,
 223};
 224module_param_cb(wait, &wait_ops, &wait, S_IRUGO);
 225MODULE_PARM_DESC(wait, "Wait for tests to complete (default: false)");
 226
 227static bool dmatest_match_channel(struct dmatest_params *params,
 228		struct dma_chan *chan)
 229{
 230	if (params->channel[0] == '\0')
 231		return true;
 232	return strcmp(dma_chan_name(chan), params->channel) == 0;
 233}
 234
 235static bool dmatest_match_device(struct dmatest_params *params,
 236		struct dma_device *device)
 237{
 238	if (params->device[0] == '\0')
 239		return true;
 240	return strcmp(dev_name(device->dev), params->device) == 0;
 241}
 242
 243static unsigned long dmatest_random(void)
 244{
 245	unsigned long buf;
 246
 247	prandom_bytes(&buf, sizeof(buf));
 248	return buf;
 249}
 250
 251static inline u8 gen_inv_idx(u8 index, bool is_memset)
 252{
 253	u8 val = is_memset ? PATTERN_MEMSET_IDX : index;
 254
 255	return ~val & PATTERN_COUNT_MASK;
 256}
 257
 258static inline u8 gen_src_value(u8 index, bool is_memset)
 259{
 260	return PATTERN_SRC | gen_inv_idx(index, is_memset);
 261}
 262
 263static inline u8 gen_dst_value(u8 index, bool is_memset)
 264{
 265	return PATTERN_DST | gen_inv_idx(index, is_memset);
 266}
 267
 268static void dmatest_init_srcs(u8 **bufs, unsigned int start, unsigned int len,
 269		unsigned int buf_size, bool is_memset)
 270{
 271	unsigned int i;
 272	u8 *buf;
 273
 274	for (; (buf = *bufs); bufs++) {
 275		for (i = 0; i < start; i++)
 276			buf[i] = gen_src_value(i, is_memset);
 277		for ( ; i < start + len; i++)
 278			buf[i] = gen_src_value(i, is_memset) | PATTERN_COPY;
 
 279		for ( ; i < buf_size; i++)
 280			buf[i] = gen_src_value(i, is_memset);
 281		buf++;
 282	}
 283}
 284
 285static void dmatest_init_dsts(u8 **bufs, unsigned int start, unsigned int len,
 286		unsigned int buf_size, bool is_memset)
 287{
 288	unsigned int i;
 289	u8 *buf;
 290
 291	for (; (buf = *bufs); bufs++) {
 292		for (i = 0; i < start; i++)
 293			buf[i] = gen_dst_value(i, is_memset);
 294		for ( ; i < start + len; i++)
 295			buf[i] = gen_dst_value(i, is_memset) |
 296						PATTERN_OVERWRITE;
 297		for ( ; i < buf_size; i++)
 298			buf[i] = gen_dst_value(i, is_memset);
 299	}
 300}
 301
 302static void dmatest_mismatch(u8 actual, u8 pattern, unsigned int index,
 303		unsigned int counter, bool is_srcbuf, bool is_memset)
 304{
 305	u8		diff = actual ^ pattern;
 306	u8		expected = pattern | gen_inv_idx(counter, is_memset);
 307	const char	*thread_name = current->comm;
 308
 309	if (is_srcbuf)
 310		pr_warn("%s: srcbuf[0x%x] overwritten! Expected %02x, got %02x\n",
 311			thread_name, index, expected, actual);
 312	else if ((pattern & PATTERN_COPY)
 313			&& (diff & (PATTERN_COPY | PATTERN_OVERWRITE)))
 314		pr_warn("%s: dstbuf[0x%x] not copied! Expected %02x, got %02x\n",
 315			thread_name, index, expected, actual);
 316	else if (diff & PATTERN_SRC)
 317		pr_warn("%s: dstbuf[0x%x] was copied! Expected %02x, got %02x\n",
 318			thread_name, index, expected, actual);
 319	else
 320		pr_warn("%s: dstbuf[0x%x] mismatch! Expected %02x, got %02x\n",
 321			thread_name, index, expected, actual);
 322}
 323
 324static unsigned int dmatest_verify(u8 **bufs, unsigned int start,
 325		unsigned int end, unsigned int counter, u8 pattern,
 326		bool is_srcbuf, bool is_memset)
 327{
 328	unsigned int i;
 329	unsigned int error_count = 0;
 330	u8 actual;
 331	u8 expected;
 332	u8 *buf;
 333	unsigned int counter_orig = counter;
 334
 335	for (; (buf = *bufs); bufs++) {
 336		counter = counter_orig;
 337		for (i = start; i < end; i++) {
 338			actual = buf[i];
 339			expected = pattern | gen_inv_idx(counter, is_memset);
 340			if (actual != expected) {
 341				if (error_count < MAX_ERROR_COUNT)
 342					dmatest_mismatch(actual, pattern, i,
 343							 counter, is_srcbuf,
 344							 is_memset);
 345				error_count++;
 346			}
 347			counter++;
 348		}
 349	}
 350
 351	if (error_count > MAX_ERROR_COUNT)
 352		pr_warn("%s: %u errors suppressed\n",
 353			current->comm, error_count - MAX_ERROR_COUNT);
 354
 355	return error_count;
 356}
 357
 
 
 
 
 
 358
 359static void dmatest_callback(void *arg)
 360{
 361	struct dmatest_done *done = arg;
 362	struct dmatest_thread *thread =
 363		container_of(done, struct dmatest_thread, test_done);
 364	if (!thread->done) {
 365		done->done = true;
 366		wake_up_all(done->wait);
 367	} else {
 368		/*
 369		 * If thread->done, it means that this callback occurred
 370		 * after the parent thread has cleaned up. This can
 371		 * happen in the case that driver doesn't implement
 372		 * the terminate_all() functionality and a dma operation
 373		 * did not occur within the timeout period
 374		 */
 375		WARN(1, "dmatest: Kernel memory may be corrupted!!\n");
 376	}
 377}
 378
 379static unsigned int min_odd(unsigned int x, unsigned int y)
 380{
 381	unsigned int val = min(x, y);
 382
 383	return val % 2 ? val : val - 1;
 384}
 385
 386static void result(const char *err, unsigned int n, unsigned int src_off,
 387		   unsigned int dst_off, unsigned int len, unsigned long data)
 388{
 389	pr_info("%s: result #%u: '%s' with src_off=0x%x dst_off=0x%x len=0x%x (%lu)\n",
 390		current->comm, n, err, src_off, dst_off, len, data);
 391}
 392
 393static void dbg_result(const char *err, unsigned int n, unsigned int src_off,
 394		       unsigned int dst_off, unsigned int len,
 395		       unsigned long data)
 396{
 397	pr_debug("%s: result #%u: '%s' with src_off=0x%x dst_off=0x%x len=0x%x (%lu)\n",
 398		 current->comm, n, err, src_off, dst_off, len, data);
 399}
 400
 401#define verbose_result(err, n, src_off, dst_off, len, data) ({	\
 402	if (verbose)						\
 403		result(err, n, src_off, dst_off, len, data);	\
 404	else							\
 405		dbg_result(err, n, src_off, dst_off, len, data);\
 406})
 407
 408static unsigned long long dmatest_persec(s64 runtime, unsigned int val)
 409{
 410	unsigned long long per_sec = 1000000;
 411
 412	if (runtime <= 0)
 413		return 0;
 414
 415	/* drop precision until runtime is 32-bits */
 416	while (runtime > UINT_MAX) {
 417		runtime >>= 1;
 418		per_sec <<= 1;
 419	}
 420
 421	per_sec *= val;
 422	do_div(per_sec, runtime);
 423	return per_sec;
 424}
 425
 426static unsigned long long dmatest_KBs(s64 runtime, unsigned long long len)
 427{
 428	return dmatest_persec(runtime, len >> 10);
 429}
 430
 431/*
 432 * This function repeatedly tests DMA transfers of various lengths and
 433 * offsets for a given operation type until it is told to exit by
 434 * kthread_stop(). There may be multiple threads running this function
 435 * in parallel for a single channel, and there may be multiple channels
 436 * being tested in parallel.
 437 *
 438 * Before each test, the source and destination buffer is initialized
 439 * with a known pattern. This pattern is different depending on
 440 * whether it's in an area which is supposed to be copied or
 441 * overwritten, and different in the source and destination buffers.
 442 * So if the DMA engine doesn't copy exactly what we tell it to copy,
 443 * we'll notice.
 444 */
 445static int dmatest_func(void *data)
 446{
 
 447	struct dmatest_thread	*thread = data;
 448	struct dmatest_done	*done = &thread->test_done;
 449	struct dmatest_info	*info;
 450	struct dmatest_params	*params;
 451	struct dma_chan		*chan;
 452	struct dma_device	*dev;
 
 453	unsigned int		error_count;
 454	unsigned int		failed_tests = 0;
 455	unsigned int		total_tests = 0;
 456	dma_cookie_t		cookie;
 457	enum dma_status		status;
 458	enum dma_ctrl_flags 	flags;
 459	u8			*pq_coefs = NULL;
 460	int			ret;
 461	int			src_cnt;
 462	int			dst_cnt;
 463	int			i;
 464	ktime_t			ktime, start, diff;
 465	ktime_t			filltime = 0;
 466	ktime_t			comparetime = 0;
 467	s64			runtime = 0;
 468	unsigned long long	total_len = 0;
 469	u8			align = 0;
 470	bool			is_memset = false;
 471
 472	set_freezable();
 473
 474	ret = -ENOMEM;
 475
 476	smp_rmb();
 477	info = thread->info;
 478	params = &info->params;
 479	chan = thread->chan;
 480	dev = chan->device;
 481	if (thread->type == DMA_MEMCPY) {
 482		align = dev->copy_align;
 483		src_cnt = dst_cnt = 1;
 484	} else if (thread->type == DMA_MEMSET) {
 485		align = dev->fill_align;
 486		src_cnt = dst_cnt = 1;
 487		is_memset = true;
 488	} else if (thread->type == DMA_XOR) {
 489		/* force odd to ensure dst = src */
 490		src_cnt = min_odd(params->xor_sources | 1, dev->max_xor);
 491		dst_cnt = 1;
 492		align = dev->xor_align;
 493	} else if (thread->type == DMA_PQ) {
 494		/* force odd to ensure dst = src */
 495		src_cnt = min_odd(params->pq_sources | 1, dma_maxpq(dev, 0));
 496		dst_cnt = 2;
 497		align = dev->pq_align;
 498
 499		pq_coefs = kmalloc(params->pq_sources + 1, GFP_KERNEL);
 500		if (!pq_coefs)
 501			goto err_thread_type;
 502
 503		for (i = 0; i < src_cnt; i++)
 504			pq_coefs[i] = 1;
 505	} else
 506		goto err_thread_type;
 507
 508	thread->srcs = kcalloc(src_cnt + 1, sizeof(u8 *), GFP_KERNEL);
 509	if (!thread->srcs)
 510		goto err_srcs;
 511
 512	thread->usrcs = kcalloc(src_cnt + 1, sizeof(u8 *), GFP_KERNEL);
 513	if (!thread->usrcs)
 514		goto err_usrcs;
 515
 516	for (i = 0; i < src_cnt; i++) {
 517		thread->usrcs[i] = kmalloc(params->buf_size + align,
 518					   GFP_KERNEL);
 519		if (!thread->usrcs[i])
 520			goto err_srcbuf;
 521
 522		/* align srcs to alignment restriction */
 523		if (align)
 524			thread->srcs[i] = PTR_ALIGN(thread->usrcs[i], align);
 525		else
 526			thread->srcs[i] = thread->usrcs[i];
 527	}
 528	thread->srcs[i] = NULL;
 529
 530	thread->dsts = kcalloc(dst_cnt + 1, sizeof(u8 *), GFP_KERNEL);
 531	if (!thread->dsts)
 532		goto err_dsts;
 533
 534	thread->udsts = kcalloc(dst_cnt + 1, sizeof(u8 *), GFP_KERNEL);
 535	if (!thread->udsts)
 536		goto err_udsts;
 537
 538	for (i = 0; i < dst_cnt; i++) {
 539		thread->udsts[i] = kmalloc(params->buf_size + align,
 540					   GFP_KERNEL);
 541		if (!thread->udsts[i])
 542			goto err_dstbuf;
 543
 544		/* align dsts to alignment restriction */
 545		if (align)
 546			thread->dsts[i] = PTR_ALIGN(thread->udsts[i], align);
 547		else
 548			thread->dsts[i] = thread->udsts[i];
 549	}
 550	thread->dsts[i] = NULL;
 551
 552	set_user_nice(current, 10);
 553
 554	/*
 555	 * src and dst buffers are freed by ourselves below
 556	 */
 557	flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
 558
 559	ktime = ktime_get();
 560	while (!kthread_should_stop()
 561	       && !(params->iterations && total_tests >= params->iterations)) {
 562		struct dma_async_tx_descriptor *tx = NULL;
 563		struct dmaengine_unmap_data *um;
 564		dma_addr_t srcs[src_cnt];
 565		dma_addr_t *dsts;
 566		unsigned int src_off, dst_off, len;
 567
 568		total_tests++;
 569
 570		/* Check if buffer count fits into map count variable (u8) */
 571		if ((src_cnt + dst_cnt) >= 255) {
 572			pr_err("too many buffers (%d of 255 supported)\n",
 573			       src_cnt + dst_cnt);
 574			break;
 575		}
 
 576
 577		if (1 << align > params->buf_size) {
 578			pr_err("%u-byte buffer too small for %d-byte alignment\n",
 579			       params->buf_size, 1 << align);
 580			break;
 581		}
 582
 583		if (params->norandom)
 584			len = params->buf_size;
 585		else
 586			len = dmatest_random() % params->buf_size + 1;
 587
 588		len = (len >> align) << align;
 589		if (!len)
 590			len = 1 << align;
 591
 592		total_len += len;
 593
 594		if (params->norandom) {
 595			src_off = 0;
 596			dst_off = 0;
 597		} else {
 
 
 
 
 598			src_off = dmatest_random() % (params->buf_size - len + 1);
 599			dst_off = dmatest_random() % (params->buf_size - len + 1);
 600
 601			src_off = (src_off >> align) << align;
 602			dst_off = (dst_off >> align) << align;
 603		}
 604
 605		if (!params->noverify) {
 606			start = ktime_get();
 607			dmatest_init_srcs(thread->srcs, src_off, len,
 608					  params->buf_size, is_memset);
 609			dmatest_init_dsts(thread->dsts, dst_off, len,
 610					  params->buf_size, is_memset);
 
 611
 612			diff = ktime_sub(ktime_get(), start);
 613			filltime = ktime_add(filltime, diff);
 614		}
 
 615
 616		um = dmaengine_get_unmap_data(dev->dev, src_cnt + dst_cnt,
 617					      GFP_KERNEL);
 618		if (!um) {
 619			failed_tests++;
 620			result("unmap data NULL", total_tests,
 621			       src_off, dst_off, len, ret);
 622			continue;
 623		}
 624
 625		um->len = params->buf_size;
 626		for (i = 0; i < src_cnt; i++) {
 627			void *buf = thread->srcs[i];
 628			struct page *pg = virt_to_page(buf);
 629			unsigned long pg_off = offset_in_page(buf);
 630
 631			um->addr[i] = dma_map_page(dev->dev, pg, pg_off,
 632						   um->len, DMA_TO_DEVICE);
 633			srcs[i] = um->addr[i] + src_off;
 634			ret = dma_mapping_error(dev->dev, um->addr[i]);
 635			if (ret) {
 636				dmaengine_unmap_put(um);
 637				result("src mapping error", total_tests,
 638				       src_off, dst_off, len, ret);
 639				failed_tests++;
 640				continue;
 641			}
 642			um->to_cnt++;
 643		}
 644		/* map with DMA_BIDIRECTIONAL to force writeback/invalidate */
 645		dsts = &um->addr[src_cnt];
 646		for (i = 0; i < dst_cnt; i++) {
 647			void *buf = thread->dsts[i];
 648			struct page *pg = virt_to_page(buf);
 649			unsigned long pg_off = offset_in_page(buf);
 650
 651			dsts[i] = dma_map_page(dev->dev, pg, pg_off, um->len,
 652					       DMA_BIDIRECTIONAL);
 653			ret = dma_mapping_error(dev->dev, dsts[i]);
 654			if (ret) {
 655				dmaengine_unmap_put(um);
 656				result("dst mapping error", total_tests,
 657				       src_off, dst_off, len, ret);
 658				failed_tests++;
 659				continue;
 660			}
 661			um->bidi_cnt++;
 662		}
 663
 664		if (thread->type == DMA_MEMCPY)
 665			tx = dev->device_prep_dma_memcpy(chan,
 666							 dsts[0] + dst_off,
 667							 srcs[0], len, flags);
 668		else if (thread->type == DMA_MEMSET)
 669			tx = dev->device_prep_dma_memset(chan,
 670						dsts[0] + dst_off,
 671						*(thread->srcs[0] + src_off),
 672						len, flags);
 673		else if (thread->type == DMA_XOR)
 674			tx = dev->device_prep_dma_xor(chan,
 675						      dsts[0] + dst_off,
 676						      srcs, src_cnt,
 677						      len, flags);
 678		else if (thread->type == DMA_PQ) {
 679			dma_addr_t dma_pq[dst_cnt];
 680
 681			for (i = 0; i < dst_cnt; i++)
 682				dma_pq[i] = dsts[i] + dst_off;
 683			tx = dev->device_prep_dma_pq(chan, dma_pq, srcs,
 684						     src_cnt, pq_coefs,
 685						     len, flags);
 686		}
 687
 688		if (!tx) {
 689			dmaengine_unmap_put(um);
 690			result("prep error", total_tests, src_off,
 691			       dst_off, len, ret);
 692			msleep(100);
 693			failed_tests++;
 694			continue;
 695		}
 696
 697		done->done = false;
 698		tx->callback = dmatest_callback;
 699		tx->callback_param = done;
 700		cookie = tx->tx_submit(tx);
 701
 702		if (dma_submit_error(cookie)) {
 703			dmaengine_unmap_put(um);
 704			result("submit error", total_tests, src_off,
 705			       dst_off, len, ret);
 706			msleep(100);
 707			failed_tests++;
 708			continue;
 709		}
 710		dma_async_issue_pending(chan);
 711
 712		wait_event_freezable_timeout(thread->done_wait, done->done,
 713					     msecs_to_jiffies(params->timeout));
 714
 715		status = dma_async_is_tx_complete(chan, cookie, NULL, NULL);
 716
 717		if (!done->done) {
 
 
 
 
 
 
 
 
 718			dmaengine_unmap_put(um);
 719			result("test timed out", total_tests, src_off, dst_off,
 720			       len, 0);
 721			failed_tests++;
 722			continue;
 723		} else if (status != DMA_COMPLETE) {
 724			dmaengine_unmap_put(um);
 725			result(status == DMA_ERROR ?
 726			       "completion error status" :
 727			       "completion busy status", total_tests, src_off,
 728			       dst_off, len, ret);
 729			failed_tests++;
 730			continue;
 731		}
 732
 733		dmaengine_unmap_put(um);
 734
 735		if (params->noverify) {
 736			verbose_result("test passed", total_tests, src_off,
 737				       dst_off, len, 0);
 738			continue;
 739		}
 740
 741		start = ktime_get();
 742		pr_debug("%s: verifying source buffer...\n", current->comm);
 743		error_count = dmatest_verify(thread->srcs, 0, src_off,
 744				0, PATTERN_SRC, true, is_memset);
 745		error_count += dmatest_verify(thread->srcs, src_off,
 746				src_off + len, src_off,
 747				PATTERN_SRC | PATTERN_COPY, true, is_memset);
 748		error_count += dmatest_verify(thread->srcs, src_off + len,
 749				params->buf_size, src_off + len,
 750				PATTERN_SRC, true, is_memset);
 751
 752		pr_debug("%s: verifying dest buffer...\n", current->comm);
 753		error_count += dmatest_verify(thread->dsts, 0, dst_off,
 754				0, PATTERN_DST, false, is_memset);
 755
 756		error_count += dmatest_verify(thread->dsts, dst_off,
 757				dst_off + len, src_off,
 758				PATTERN_SRC | PATTERN_COPY, false, is_memset);
 759
 760		error_count += dmatest_verify(thread->dsts, dst_off + len,
 761				params->buf_size, dst_off + len,
 762				PATTERN_DST, false, is_memset);
 763
 764		diff = ktime_sub(ktime_get(), start);
 765		comparetime = ktime_add(comparetime, diff);
 766
 767		if (error_count) {
 768			result("data error", total_tests, src_off, dst_off,
 769			       len, error_count);
 770			failed_tests++;
 771		} else {
 772			verbose_result("test passed", total_tests, src_off,
 773				       dst_off, len, 0);
 774		}
 775	}
 776	ktime = ktime_sub(ktime_get(), ktime);
 777	ktime = ktime_sub(ktime, comparetime);
 778	ktime = ktime_sub(ktime, filltime);
 779	runtime = ktime_to_us(ktime);
 780
 781	ret = 0;
 
 
 782err_dstbuf:
 783	for (i = 0; thread->udsts[i]; i++)
 784		kfree(thread->udsts[i]);
 785	kfree(thread->udsts);
 786err_udsts:
 787	kfree(thread->dsts);
 788err_dsts:
 
 
 789err_srcbuf:
 790	for (i = 0; thread->usrcs[i]; i++)
 791		kfree(thread->usrcs[i]);
 792	kfree(thread->usrcs);
 793err_usrcs:
 794	kfree(thread->srcs);
 795err_srcs:
 796	kfree(pq_coefs);
 797err_thread_type:
 798	pr_info("%s: summary %u tests, %u failures %llu iops %llu KB/s (%d)\n",
 799		current->comm, total_tests, failed_tests,
 800		dmatest_persec(runtime, total_tests),
 801		dmatest_KBs(runtime, total_len), ret);
 802
 803	/* terminate all transfers on specified channels */
 804	if (ret || failed_tests)
 805		dmaengine_terminate_all(chan);
 806
 807	thread->done = true;
 808	wake_up(&thread_wait);
 809
 810	return ret;
 811}
 812
 813static void dmatest_cleanup_channel(struct dmatest_chan *dtc)
 814{
 815	struct dmatest_thread	*thread;
 816	struct dmatest_thread	*_thread;
 817	int			ret;
 818
 819	list_for_each_entry_safe(thread, _thread, &dtc->threads, node) {
 820		ret = kthread_stop(thread->task);
 821		pr_debug("thread %s exited with status %d\n",
 822			 thread->task->comm, ret);
 823		list_del(&thread->node);
 824		put_task_struct(thread->task);
 825		kfree(thread);
 826	}
 827
 828	/* terminate all transfers on specified channels */
 829	dmaengine_terminate_all(dtc->chan);
 830
 831	kfree(dtc);
 832}
 833
 834static int dmatest_add_threads(struct dmatest_info *info,
 835		struct dmatest_chan *dtc, enum dma_transaction_type type)
 836{
 837	struct dmatest_params *params = &info->params;
 838	struct dmatest_thread *thread;
 839	struct dma_chan *chan = dtc->chan;
 840	char *op;
 841	unsigned int i;
 842
 843	if (type == DMA_MEMCPY)
 844		op = "copy";
 845	else if (type == DMA_MEMSET)
 846		op = "set";
 847	else if (type == DMA_XOR)
 848		op = "xor";
 849	else if (type == DMA_PQ)
 850		op = "pq";
 851	else
 852		return -EINVAL;
 853
 854	for (i = 0; i < params->threads_per_chan; i++) {
 855		thread = kzalloc(sizeof(struct dmatest_thread), GFP_KERNEL);
 856		if (!thread) {
 857			pr_warn("No memory for %s-%s%u\n",
 858				dma_chan_name(chan), op, i);
 859			break;
 860		}
 861		thread->info = info;
 862		thread->chan = dtc->chan;
 863		thread->type = type;
 864		thread->test_done.wait = &thread->done_wait;
 865		init_waitqueue_head(&thread->done_wait);
 866		smp_wmb();
 867		thread->task = kthread_create(dmatest_func, thread, "%s-%s%u",
 868				dma_chan_name(chan), op, i);
 869		if (IS_ERR(thread->task)) {
 870			pr_warn("Failed to create thread %s-%s%u\n",
 871				dma_chan_name(chan), op, i);
 872			kfree(thread);
 873			break;
 874		}
 875
 876		/* srcbuf and dstbuf are allocated by the thread itself */
 877		get_task_struct(thread->task);
 878		list_add_tail(&thread->node, &dtc->threads);
 879		wake_up_process(thread->task);
 880	}
 881
 882	return i;
 883}
 884
 885static int dmatest_add_channel(struct dmatest_info *info,
 886		struct dma_chan *chan)
 887{
 888	struct dmatest_chan	*dtc;
 889	struct dma_device	*dma_dev = chan->device;
 890	unsigned int		thread_count = 0;
 891	int cnt;
 892
 893	dtc = kmalloc(sizeof(struct dmatest_chan), GFP_KERNEL);
 894	if (!dtc) {
 895		pr_warn("No memory for %s\n", dma_chan_name(chan));
 896		return -ENOMEM;
 897	}
 898
 899	dtc->chan = chan;
 900	INIT_LIST_HEAD(&dtc->threads);
 901
 902	if (dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask)) {
 903		if (dmatest == 0) {
 904			cnt = dmatest_add_threads(info, dtc, DMA_MEMCPY);
 905			thread_count += cnt > 0 ? cnt : 0;
 906		}
 907	}
 908
 909	if (dma_has_cap(DMA_MEMSET, dma_dev->cap_mask)) {
 910		if (dmatest == 1) {
 911			cnt = dmatest_add_threads(info, dtc, DMA_MEMSET);
 912			thread_count += cnt > 0 ? cnt : 0;
 913		}
 914	}
 915
 916	if (dma_has_cap(DMA_XOR, dma_dev->cap_mask)) {
 917		cnt = dmatest_add_threads(info, dtc, DMA_XOR);
 918		thread_count += cnt > 0 ? cnt : 0;
 919	}
 920	if (dma_has_cap(DMA_PQ, dma_dev->cap_mask)) {
 921		cnt = dmatest_add_threads(info, dtc, DMA_PQ);
 922		thread_count += cnt > 0 ? cnt : 0;
 923	}
 924
 925	pr_info("Started %u threads using %s\n",
 926		thread_count, dma_chan_name(chan));
 927
 928	list_add_tail(&dtc->node, &info->channels);
 929	info->nr_channels++;
 930
 931	return 0;
 932}
 933
 934static bool filter(struct dma_chan *chan, void *param)
 935{
 936	struct dmatest_params *params = param;
 937
 938	if (!dmatest_match_channel(params, chan) ||
 939	    !dmatest_match_device(params, chan->device))
 940		return false;
 941	else
 942		return true;
 943}
 944
 945static void request_channels(struct dmatest_info *info,
 946			     enum dma_transaction_type type)
 947{
 948	dma_cap_mask_t mask;
 949
 950	dma_cap_zero(mask);
 951	dma_cap_set(type, mask);
 952	for (;;) {
 953		struct dmatest_params *params = &info->params;
 954		struct dma_chan *chan;
 955
 956		chan = dma_request_channel(mask, filter, params);
 957		if (chan) {
 958			if (dmatest_add_channel(info, chan)) {
 959				dma_release_channel(chan);
 960				break; /* add_channel failed, punt */
 961			}
 962		} else
 963			break; /* no more channels available */
 964		if (params->max_channels &&
 965		    info->nr_channels >= params->max_channels)
 966			break; /* we have all we need */
 967	}
 968}
 969
 970static void run_threaded_test(struct dmatest_info *info)
 971{
 972	struct dmatest_params *params = &info->params;
 973
 974	/* Copy test parameters */
 975	params->buf_size = test_buf_size;
 976	strlcpy(params->channel, strim(test_channel), sizeof(params->channel));
 977	strlcpy(params->device, strim(test_device), sizeof(params->device));
 978	params->threads_per_chan = threads_per_chan;
 979	params->max_channels = max_channels;
 980	params->iterations = iterations;
 981	params->xor_sources = xor_sources;
 982	params->pq_sources = pq_sources;
 983	params->timeout = timeout;
 984	params->noverify = noverify;
 985	params->norandom = norandom;
 986
 987	request_channels(info, DMA_MEMCPY);
 988	request_channels(info, DMA_MEMSET);
 989	request_channels(info, DMA_XOR);
 990	request_channels(info, DMA_PQ);
 991}
 992
 993static void stop_threaded_test(struct dmatest_info *info)
 994{
 995	struct dmatest_chan *dtc, *_dtc;
 996	struct dma_chan *chan;
 997
 998	list_for_each_entry_safe(dtc, _dtc, &info->channels, node) {
 999		list_del(&dtc->node);
1000		chan = dtc->chan;
1001		dmatest_cleanup_channel(dtc);
1002		pr_debug("dropped channel %s\n", dma_chan_name(chan));
1003		dma_release_channel(chan);
1004	}
1005
1006	info->nr_channels = 0;
1007}
1008
1009static void restart_threaded_test(struct dmatest_info *info, bool run)
1010{
1011	/* we might be called early to set run=, defer running until all
1012	 * parameters have been evaluated
1013	 */
1014	if (!info->did_init)
1015		return;
1016
1017	/* Stop any running test first */
1018	stop_threaded_test(info);
1019
1020	/* Run test with new parameters */
1021	run_threaded_test(info);
1022}
1023
1024static int dmatest_run_get(char *val, const struct kernel_param *kp)
1025{
1026	struct dmatest_info *info = &test_info;
1027
1028	mutex_lock(&info->lock);
1029	if (is_threaded_test_run(info)) {
1030		dmatest_run = true;
1031	} else {
1032		stop_threaded_test(info);
1033		dmatest_run = false;
1034	}
1035	mutex_unlock(&info->lock);
1036
1037	return param_get_bool(val, kp);
1038}
1039
1040static int dmatest_run_set(const char *val, const struct kernel_param *kp)
1041{
1042	struct dmatest_info *info = &test_info;
1043	int ret;
1044
1045	mutex_lock(&info->lock);
1046	ret = param_set_bool(val, kp);
1047	if (ret) {
1048		mutex_unlock(&info->lock);
1049		return ret;
1050	}
1051
1052	if (is_threaded_test_run(info))
1053		ret = -EBUSY;
1054	else if (dmatest_run)
1055		restart_threaded_test(info, dmatest_run);
1056
1057	mutex_unlock(&info->lock);
1058
1059	return ret;
1060}
1061
1062static int __init dmatest_init(void)
1063{
1064	struct dmatest_info *info = &test_info;
1065	struct dmatest_params *params = &info->params;
1066
1067	if (dmatest_run) {
1068		mutex_lock(&info->lock);
1069		run_threaded_test(info);
1070		mutex_unlock(&info->lock);
1071	}
1072
1073	if (params->iterations && wait)
1074		wait_event(thread_wait, !is_threaded_test_run(info));
1075
1076	/* module parameters are stable, inittime tests are started,
1077	 * let userspace take over 'run' control
1078	 */
1079	info->did_init = true;
1080
1081	return 0;
1082}
1083/* when compiled-in wait for drivers to load first */
1084late_initcall(dmatest_init);
1085
1086static void __exit dmatest_exit(void)
1087{
1088	struct dmatest_info *info = &test_info;
1089
1090	mutex_lock(&info->lock);
1091	stop_threaded_test(info);
1092	mutex_unlock(&info->lock);
1093}
1094module_exit(dmatest_exit);
1095
1096MODULE_AUTHOR("Haavard Skinnemoen (Atmel)");
1097MODULE_LICENSE("GPL v2");