xref: /linux/drivers/ntb/test/ntb_perf.c (revision ae07abdb84b267627f6e10fb813e62de5c3c8117)
1 /*
2  * This file is provided under a dual BSD/GPLv2 license.  When using or
3  *   redistributing this file, you may do so under either license.
4  *
5  *   GPL LICENSE SUMMARY
6  *
7  *   Copyright(c) 2015 Intel Corporation. All rights reserved.
8  *   Copyright(c) 2017 T-Platforms. All Rights Reserved.
9  *
10  *   This program is free software; you can redistribute it and/or modify
11  *   it under the terms of version 2 of the GNU General Public License as
12  *   published by the Free Software Foundation.
13  *
14  *   BSD LICENSE
15  *
16  *   Copyright(c) 2015 Intel Corporation. All rights reserved.
17  *   Copyright(c) 2017 T-Platforms. All Rights Reserved.
18  *
19  *   Redistribution and use in source and binary forms, with or without
20  *   modification, are permitted provided that the following conditions
21  *   are met:
22  *
23  *     * Redistributions of source code must retain the above copyright
24  *       notice, this list of conditions and the following disclaimer.
25  *     * Redistributions in binary form must reproduce the above copy
26  *       notice, this list of conditions and the following disclaimer in
27  *       the documentation and/or other materials provided with the
28  *       distribution.
29  *     * Neither the name of Intel Corporation nor the names of its
30  *       contributors may be used to endorse or promote products derived
31  *       from this software without specific prior written permission.
32  *
33  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
34  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
35  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
36  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
37  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
38  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
39  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
40  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
41  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
42  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
43  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
44  *
45  * PCIe NTB Perf Linux driver
46  */
47 
48 /*
49  * How to use this tool, by example.
50  *
51  * Assuming $DBG_DIR is something like:
52  * '/sys/kernel/debug/ntb_perf/0000:00:03.0'
53  * Suppose aside from local device there is at least one remote device
54  * connected to NTB with index 0.
55  *-----------------------------------------------------------------------------
56  * Eg: install driver with specified chunk/total orders and dma-enabled flag
57  *
58  * root@self# insmod ntb_perf.ko chunk_order=19 total_order=28 use_dma
59  *-----------------------------------------------------------------------------
60  * Eg: check NTB ports (index) and MW mapping information
61  *
62  * root@self# cat $DBG_DIR/info
63  *-----------------------------------------------------------------------------
64  * Eg: start performance test with peer (index 0) and get the test metrics
65  *
66  * root@self# echo 0 > $DBG_DIR/run
67  * root@self# cat $DBG_DIR/run
68  */
69 
70 #include <linux/init.h>
71 #include <linux/kernel.h>
72 #include <linux/module.h>
73 #include <linux/sched.h>
74 #include <linux/wait.h>
75 #include <linux/dma-mapping.h>
76 #include <linux/dmaengine.h>
77 #include <linux/pci.h>
78 #include <linux/ktime.h>
79 #include <linux/slab.h>
80 #include <linux/delay.h>
81 #include <linux/sizes.h>
82 #include <linux/workqueue.h>
83 #include <linux/debugfs.h>
84 #include <linux/random.h>
85 #include <linux/ntb.h>
86 
87 #define DRIVER_NAME		"ntb_perf"
88 #define DRIVER_VERSION		"2.0"
89 
90 MODULE_LICENSE("Dual BSD/GPL");
91 MODULE_VERSION(DRIVER_VERSION);
92 MODULE_AUTHOR("Dave Jiang <dave.jiang@intel.com>");
93 MODULE_DESCRIPTION("PCIe NTB Performance Measurement Tool");
94 
95 #define MAX_THREADS_CNT		32
96 #define DEF_THREADS_CNT		1
97 #define MAX_CHUNK_SIZE		SZ_1M
98 #define MAX_CHUNK_ORDER		20 /* no larger than 1M */
99 
100 #define DMA_TRIES		100
101 #define DMA_MDELAY		10
102 
103 #define MSG_TRIES		500
104 #define MSG_UDELAY_LOW		1000
105 #define MSG_UDELAY_HIGH		2000
106 
107 #define PERF_BUF_LEN 1024
108 
109 static unsigned long max_mw_size;
110 module_param(max_mw_size, ulong, 0644);
111 MODULE_PARM_DESC(max_mw_size, "Upper limit of memory window size");
112 
113 static unsigned char chunk_order = 19; /* 512K */
114 module_param(chunk_order, byte, 0644);
115 MODULE_PARM_DESC(chunk_order, "Data chunk order [2^n] to transfer");
116 
117 static unsigned char total_order = 30; /* 1G */
118 module_param(total_order, byte, 0644);
119 MODULE_PARM_DESC(total_order, "Total data order [2^n] to transfer");
120 
121 static bool use_dma; /* default to 0 */
122 module_param(use_dma, bool, 0644);
123 MODULE_PARM_DESC(use_dma, "Use DMA engine to measure performance");
124 
125 /*==============================================================================
126  *                         Perf driver data definition
127  *==============================================================================
128  */
129 
130 enum perf_cmd {
131 	PERF_CMD_INVAL = -1,/* invalid spad command */
132 	PERF_CMD_SSIZE = 0, /* send out buffer size */
133 	PERF_CMD_RSIZE = 1, /* recv in  buffer size */
134 	PERF_CMD_SXLAT = 2, /* send in  buffer xlat */
135 	PERF_CMD_RXLAT = 3, /* recv out buffer xlat */
136 	PERF_CMD_CLEAR = 4, /* clear allocated memory */
137 	PERF_STS_DONE  = 5, /* init is done */
138 	PERF_STS_LNKUP = 6, /* link up state flag */
139 };
140 
141 struct perf_ctx;
142 
143 struct perf_peer {
144 	struct perf_ctx	*perf;
145 	int pidx;
146 	int gidx;
147 
148 	/* Outbound MW params */
149 	u64 outbuf_xlat;
150 	resource_size_t outbuf_size;
151 	void __iomem *outbuf;
152 
153 	/* Inbound MW params */
154 	dma_addr_t inbuf_xlat;
155 	resource_size_t inbuf_size;
156 	void		*inbuf;
157 
158 	/* NTB connection setup service */
159 	struct work_struct	service;
160 	unsigned long		sts;
161 };
162 #define to_peer_service(__work) \
163 	container_of(__work, struct perf_peer, service)
164 
165 struct perf_thread {
166 	struct perf_ctx *perf;
167 	int tidx;
168 
169 	/* DMA-based test sync parameters */
170 	atomic_t dma_sync;
171 	wait_queue_head_t dma_wait;
172 	struct dma_chan *dma_chan;
173 
174 	/* Data source and measured statistics */
175 	void *src;
176 	u64 copied;
177 	ktime_t duration;
178 	int status;
179 	struct work_struct work;
180 };
181 #define to_thread_work(__work) \
182 	container_of(__work, struct perf_thread, work)
183 
184 struct perf_ctx {
185 	struct ntb_dev *ntb;
186 
187 	/* Global device index and peers descriptors */
188 	int gidx;
189 	int pcnt;
190 	struct perf_peer *peers;
191 
192 	/* Performance measuring work-threads interface */
193 	unsigned long busy_flag;
194 	wait_queue_head_t twait;
195 	atomic_t tsync;
196 	u8 tcnt;
197 	struct perf_peer *test_peer;
198 	struct perf_thread threads[MAX_THREADS_CNT];
199 
200 	/* Scratchpad/Message IO operations */
201 	int (*cmd_send)(struct perf_peer *peer, enum perf_cmd cmd, u64 data);
202 	int (*cmd_recv)(struct perf_ctx *perf, int *pidx, enum perf_cmd *cmd,
203 			u64 *data);
204 
205 	struct dentry *dbgfs_dir;
206 };
207 
208 /*
209  * Scratchpads-base commands interface
210  */
211 #define PERF_SPAD_CNT(_pcnt) \
212 	(3*((_pcnt) + 1))
213 #define PERF_SPAD_CMD(_gidx) \
214 	(3*(_gidx))
215 #define PERF_SPAD_LDATA(_gidx) \
216 	(3*(_gidx) + 1)
217 #define PERF_SPAD_HDATA(_gidx) \
218 	(3*(_gidx) + 2)
219 #define PERF_SPAD_NOTIFY(_gidx) \
220 	(BIT_ULL(_gidx))
221 
222 /*
223  * Messages-base commands interface
224  */
225 #define PERF_MSG_CNT		3
226 #define PERF_MSG_CMD		0
227 #define PERF_MSG_LDATA		1
228 #define PERF_MSG_HDATA		2
229 
230 /*==============================================================================
231  *                           Static data declarations
232  *==============================================================================
233  */
234 
235 static struct dentry *perf_dbgfs_topdir;
236 
237 static struct workqueue_struct *perf_wq __read_mostly;
238 
239 /*==============================================================================
240  *                  NTB cross-link commands execution service
241  *==============================================================================
242  */
243 
244 static void perf_terminate_test(struct perf_ctx *perf);
245 
246 static inline bool perf_link_is_up(struct perf_peer *peer)
247 {
248 	u64 link;
249 
250 	link = ntb_link_is_up(peer->perf->ntb, NULL, NULL);
251 	return !!(link & BIT_ULL_MASK(peer->pidx));
252 }
253 
254 static int perf_spad_cmd_send(struct perf_peer *peer, enum perf_cmd cmd,
255 			      u64 data)
256 {
257 	struct perf_ctx *perf = peer->perf;
258 	int try;
259 	u32 sts;
260 
261 	dev_dbg(&perf->ntb->dev, "CMD send: %d 0x%llx\n", cmd, data);
262 
263 	/*
264 	 * Perform predefined number of attempts before give up.
265 	 * We are sending the data to the port specific scratchpad, so
266 	 * to prevent a multi-port access race-condition. Additionally
267 	 * there is no need in local locking since only thread-safe
268 	 * service work is using this method.
269 	 */
270 	for (try = 0; try < MSG_TRIES; try++) {
271 		if (!perf_link_is_up(peer))
272 			return -ENOLINK;
273 
274 		sts = ntb_peer_spad_read(perf->ntb, peer->pidx,
275 					 PERF_SPAD_CMD(perf->gidx));
276 		if (le32_to_cpu(sts) != PERF_CMD_INVAL) {
277 			usleep_range(MSG_UDELAY_LOW, MSG_UDELAY_HIGH);
278 			continue;
279 		}
280 
281 		ntb_peer_spad_write(perf->ntb, peer->pidx,
282 				    PERF_SPAD_LDATA(perf->gidx),
283 				    cpu_to_le32(lower_32_bits(data)));
284 		ntb_peer_spad_write(perf->ntb, peer->pidx,
285 				    PERF_SPAD_HDATA(perf->gidx),
286 				    cpu_to_le32(upper_32_bits(data)));
287 		mmiowb();
288 		ntb_peer_spad_write(perf->ntb, peer->pidx,
289 				    PERF_SPAD_CMD(perf->gidx),
290 				    cpu_to_le32(cmd));
291 		mmiowb();
292 		ntb_peer_db_set(perf->ntb, PERF_SPAD_NOTIFY(peer->gidx));
293 
294 		dev_dbg(&perf->ntb->dev, "DB ring peer %#llx\n",
295 			PERF_SPAD_NOTIFY(peer->gidx));
296 
297 		break;
298 	}
299 
300 	return try < MSG_TRIES ? 0 : -EAGAIN;
301 }
302 
303 static int perf_spad_cmd_recv(struct perf_ctx *perf, int *pidx,
304 			      enum perf_cmd *cmd, u64 *data)
305 {
306 	struct perf_peer *peer;
307 	u32 val;
308 
309 	ntb_db_clear(perf->ntb, PERF_SPAD_NOTIFY(perf->gidx));
310 
311 	/*
312 	 * We start scanning all over, since cleared DB may have been set
313 	 * by any peer. Yes, it makes peer with smaller index being
314 	 * serviced with greater priority, but it's convenient for spad
315 	 * and message code unification and simplicity.
316 	 */
317 	for (*pidx = 0; *pidx < perf->pcnt; (*pidx)++) {
318 		peer = &perf->peers[*pidx];
319 
320 		if (!perf_link_is_up(peer))
321 			continue;
322 
323 		val = ntb_spad_read(perf->ntb, PERF_SPAD_CMD(peer->gidx));
324 		val = le32_to_cpu(val);
325 		if (val == PERF_CMD_INVAL)
326 			continue;
327 
328 		*cmd = val;
329 
330 		val = ntb_spad_read(perf->ntb, PERF_SPAD_LDATA(peer->gidx));
331 		*data = le32_to_cpu(val);
332 
333 		val = ntb_spad_read(perf->ntb, PERF_SPAD_HDATA(peer->gidx));
334 		*data |= (u64)le32_to_cpu(val) << 32;
335 
336 		/* Next command can be retrieved from now */
337 		ntb_spad_write(perf->ntb, PERF_SPAD_CMD(peer->gidx),
338 			       cpu_to_le32(PERF_CMD_INVAL));
339 
340 		dev_dbg(&perf->ntb->dev, "CMD recv: %d 0x%llx\n", *cmd, *data);
341 
342 		return 0;
343 	}
344 
345 	return -ENODATA;
346 }
347 
348 static int perf_msg_cmd_send(struct perf_peer *peer, enum perf_cmd cmd,
349 			     u64 data)
350 {
351 	struct perf_ctx *perf = peer->perf;
352 	int try, ret;
353 	u64 outbits;
354 
355 	dev_dbg(&perf->ntb->dev, "CMD send: %d 0x%llx\n", cmd, data);
356 
357 	/*
358 	 * Perform predefined number of attempts before give up. Message
359 	 * registers are free of race-condition problem when accessed
360 	 * from different ports, so we don't need splitting registers
361 	 * by global device index. We also won't have local locking,
362 	 * since the method is used from service work only.
363 	 */
364 	outbits = ntb_msg_outbits(perf->ntb);
365 	for (try = 0; try < MSG_TRIES; try++) {
366 		if (!perf_link_is_up(peer))
367 			return -ENOLINK;
368 
369 		ret = ntb_msg_clear_sts(perf->ntb, outbits);
370 		if (ret)
371 			return ret;
372 
373 		ntb_peer_msg_write(perf->ntb, peer->pidx, PERF_MSG_LDATA,
374 			      cpu_to_le32(lower_32_bits(data)));
375 
376 		if (ntb_msg_read_sts(perf->ntb) & outbits) {
377 			usleep_range(MSG_UDELAY_LOW, MSG_UDELAY_HIGH);
378 			continue;
379 		}
380 
381 		ntb_peer_msg_write(perf->ntb, peer->pidx, PERF_MSG_HDATA,
382 			      cpu_to_le32(upper_32_bits(data)));
383 		mmiowb();
384 
385 		/* This call shall trigger peer message event */
386 		ntb_peer_msg_write(perf->ntb, peer->pidx, PERF_MSG_CMD,
387 			      cpu_to_le32(cmd));
388 
389 		break;
390 	}
391 
392 	return try < MSG_TRIES ? 0 : -EAGAIN;
393 }
394 
395 static int perf_msg_cmd_recv(struct perf_ctx *perf, int *pidx,
396 			     enum perf_cmd *cmd, u64 *data)
397 {
398 	u64 inbits;
399 	u32 val;
400 
401 	inbits = ntb_msg_inbits(perf->ntb);
402 
403 	if (hweight64(ntb_msg_read_sts(perf->ntb) & inbits) < 3)
404 		return -ENODATA;
405 
406 	val = ntb_msg_read(perf->ntb, pidx, PERF_MSG_CMD);
407 	*cmd = le32_to_cpu(val);
408 
409 	val = ntb_msg_read(perf->ntb, pidx, PERF_MSG_LDATA);
410 	*data = le32_to_cpu(val);
411 
412 	val = ntb_msg_read(perf->ntb, pidx, PERF_MSG_HDATA);
413 	*data |= (u64)le32_to_cpu(val) << 32;
414 
415 	/* Next command can be retrieved from now */
416 	ntb_msg_clear_sts(perf->ntb, inbits);
417 
418 	dev_dbg(&perf->ntb->dev, "CMD recv: %d 0x%llx\n", *cmd, *data);
419 
420 	return 0;
421 }
422 
423 static int perf_cmd_send(struct perf_peer *peer, enum perf_cmd cmd, u64 data)
424 {
425 	struct perf_ctx *perf = peer->perf;
426 
427 	if (cmd == PERF_CMD_SSIZE || cmd == PERF_CMD_SXLAT)
428 		return perf->cmd_send(peer, cmd, data);
429 
430 	dev_err(&perf->ntb->dev, "Send invalid command\n");
431 	return -EINVAL;
432 }
433 
434 static int perf_cmd_exec(struct perf_peer *peer, enum perf_cmd cmd)
435 {
436 	switch (cmd) {
437 	case PERF_CMD_SSIZE:
438 	case PERF_CMD_RSIZE:
439 	case PERF_CMD_SXLAT:
440 	case PERF_CMD_RXLAT:
441 	case PERF_CMD_CLEAR:
442 		break;
443 	default:
444 		dev_err(&peer->perf->ntb->dev, "Exec invalid command\n");
445 		return -EINVAL;
446 	}
447 
448 	/* No need of memory barrier, since bit ops have invernal lock */
449 	set_bit(cmd, &peer->sts);
450 
451 	dev_dbg(&peer->perf->ntb->dev, "CMD exec: %d\n", cmd);
452 
453 	(void)queue_work(system_highpri_wq, &peer->service);
454 
455 	return 0;
456 }
457 
458 static int perf_cmd_recv(struct perf_ctx *perf)
459 {
460 	struct perf_peer *peer;
461 	int ret, pidx, cmd;
462 	u64 data;
463 
464 	while (!(ret = perf->cmd_recv(perf, &pidx, &cmd, &data))) {
465 		peer = &perf->peers[pidx];
466 
467 		switch (cmd) {
468 		case PERF_CMD_SSIZE:
469 			peer->inbuf_size = data;
470 			return perf_cmd_exec(peer, PERF_CMD_RSIZE);
471 		case PERF_CMD_SXLAT:
472 			peer->outbuf_xlat = data;
473 			return perf_cmd_exec(peer, PERF_CMD_RXLAT);
474 		default:
475 			dev_err(&perf->ntb->dev, "Recv invalid command\n");
476 			return -EINVAL;
477 		}
478 	}
479 
480 	/* Return 0 if no data left to process, otherwise an error */
481 	return ret == -ENODATA ? 0 : ret;
482 }
483 
484 static void perf_link_event(void *ctx)
485 {
486 	struct perf_ctx *perf = ctx;
487 	struct perf_peer *peer;
488 	bool lnk_up;
489 	int pidx;
490 
491 	for (pidx = 0; pidx < perf->pcnt; pidx++) {
492 		peer = &perf->peers[pidx];
493 
494 		lnk_up = perf_link_is_up(peer);
495 
496 		if (lnk_up &&
497 		    !test_and_set_bit(PERF_STS_LNKUP, &peer->sts)) {
498 			perf_cmd_exec(peer, PERF_CMD_SSIZE);
499 		} else if (!lnk_up &&
500 			   test_and_clear_bit(PERF_STS_LNKUP, &peer->sts)) {
501 			perf_cmd_exec(peer, PERF_CMD_CLEAR);
502 		}
503 	}
504 }
505 
506 static void perf_db_event(void *ctx, int vec)
507 {
508 	struct perf_ctx *perf = ctx;
509 
510 	dev_dbg(&perf->ntb->dev, "DB vec %d mask %#llx bits %#llx\n", vec,
511 		ntb_db_vector_mask(perf->ntb, vec), ntb_db_read(perf->ntb));
512 
513 	/* Just receive all available commands */
514 	(void)perf_cmd_recv(perf);
515 }
516 
517 static void perf_msg_event(void *ctx)
518 {
519 	struct perf_ctx *perf = ctx;
520 
521 	dev_dbg(&perf->ntb->dev, "Msg status bits %#llx\n",
522 		ntb_msg_read_sts(perf->ntb));
523 
524 	/* Messages are only sent one-by-one */
525 	(void)perf_cmd_recv(perf);
526 }
527 
528 static const struct ntb_ctx_ops perf_ops = {
529 	.link_event = perf_link_event,
530 	.db_event = perf_db_event,
531 	.msg_event = perf_msg_event
532 };
533 
534 static void perf_free_outbuf(struct perf_peer *peer)
535 {
536 	(void)ntb_peer_mw_clear_trans(peer->perf->ntb, peer->pidx, peer->gidx);
537 }
538 
539 static int perf_setup_outbuf(struct perf_peer *peer)
540 {
541 	struct perf_ctx *perf = peer->perf;
542 	int ret;
543 
544 	/* Outbuf size can be unaligned due to custom max_mw_size */
545 	ret = ntb_peer_mw_set_trans(perf->ntb, peer->pidx, peer->gidx,
546 				    peer->outbuf_xlat, peer->outbuf_size);
547 	if (ret) {
548 		dev_err(&perf->ntb->dev, "Failed to set outbuf translation\n");
549 		return ret;
550 	}
551 
552 	/* Initialization is finally done */
553 	set_bit(PERF_STS_DONE, &peer->sts);
554 
555 	return 0;
556 }
557 
558 static void perf_free_inbuf(struct perf_peer *peer)
559 {
560 	if (!peer->inbuf)
561 		return;
562 
563 	(void)ntb_mw_clear_trans(peer->perf->ntb, peer->pidx, peer->gidx);
564 	dma_free_coherent(&peer->perf->ntb->dev, peer->inbuf_size,
565 			  peer->inbuf, peer->inbuf_xlat);
566 	peer->inbuf = NULL;
567 }
568 
569 static int perf_setup_inbuf(struct perf_peer *peer)
570 {
571 	resource_size_t xlat_align, size_align, size_max;
572 	struct perf_ctx *perf = peer->perf;
573 	int ret;
574 
575 	/* Get inbound MW parameters */
576 	ret = ntb_mw_get_align(perf->ntb, peer->pidx, perf->gidx,
577 			       &xlat_align, &size_align, &size_max);
578 	if (ret) {
579 		dev_err(&perf->ntb->dev, "Couldn't get inbuf restrictions\n");
580 		return ret;
581 	}
582 
583 	if (peer->inbuf_size > size_max) {
584 		dev_err(&perf->ntb->dev, "Too big inbuf size %pa > %pa\n",
585 			&peer->inbuf_size, &size_max);
586 		return -EINVAL;
587 	}
588 
589 	peer->inbuf_size = round_up(peer->inbuf_size, size_align);
590 
591 	perf_free_inbuf(peer);
592 
593 	peer->inbuf = dma_alloc_coherent(&perf->ntb->dev, peer->inbuf_size,
594 					 &peer->inbuf_xlat, GFP_KERNEL);
595 	if (!peer->inbuf) {
596 		dev_err(&perf->ntb->dev, "Failed to alloc inbuf of %pa\n",
597 			&peer->inbuf_size);
598 		return -ENOMEM;
599 	}
600 	if (!IS_ALIGNED(peer->inbuf_xlat, xlat_align)) {
601 		dev_err(&perf->ntb->dev, "Unaligned inbuf allocated\n");
602 		goto err_free_inbuf;
603 	}
604 
605 	ret = ntb_mw_set_trans(perf->ntb, peer->pidx, peer->gidx,
606 			       peer->inbuf_xlat, peer->inbuf_size);
607 	if (ret) {
608 		dev_err(&perf->ntb->dev, "Failed to set inbuf translation\n");
609 		goto err_free_inbuf;
610 	}
611 
612 	/*
613 	 * We submit inbuf xlat transmission cmd for execution here to follow
614 	 * the code architecture, even though this method is called from service
615 	 * work itself so the command will be executed right after it returns.
616 	 */
617 	(void)perf_cmd_exec(peer, PERF_CMD_SXLAT);
618 
619 	return 0;
620 
621 err_free_inbuf:
622 	perf_free_inbuf(peer);
623 
624 	return ret;
625 }
626 
627 static void perf_service_work(struct work_struct *work)
628 {
629 	struct perf_peer *peer = to_peer_service(work);
630 
631 	if (test_and_clear_bit(PERF_CMD_SSIZE, &peer->sts))
632 		perf_cmd_send(peer, PERF_CMD_SSIZE, peer->outbuf_size);
633 
634 	if (test_and_clear_bit(PERF_CMD_RSIZE, &peer->sts))
635 		perf_setup_inbuf(peer);
636 
637 	if (test_and_clear_bit(PERF_CMD_SXLAT, &peer->sts))
638 		perf_cmd_send(peer, PERF_CMD_SXLAT, peer->inbuf_xlat);
639 
640 	if (test_and_clear_bit(PERF_CMD_RXLAT, &peer->sts))
641 		perf_setup_outbuf(peer);
642 
643 	if (test_and_clear_bit(PERF_CMD_CLEAR, &peer->sts)) {
644 		clear_bit(PERF_STS_DONE, &peer->sts);
645 		if (test_bit(0, &peer->perf->busy_flag) &&
646 		    peer == peer->perf->test_peer) {
647 			dev_warn(&peer->perf->ntb->dev,
648 				"Freeing while test on-fly\n");
649 			perf_terminate_test(peer->perf);
650 		}
651 		perf_free_outbuf(peer);
652 		perf_free_inbuf(peer);
653 	}
654 }
655 
656 static int perf_init_service(struct perf_ctx *perf)
657 {
658 	u64 mask;
659 
660 	if (ntb_peer_mw_count(perf->ntb) < perf->pcnt + 1) {
661 		dev_err(&perf->ntb->dev, "Not enough memory windows\n");
662 		return -EINVAL;
663 	}
664 
665 	if (ntb_msg_count(perf->ntb) >= PERF_MSG_CNT) {
666 		perf->cmd_send = perf_msg_cmd_send;
667 		perf->cmd_recv = perf_msg_cmd_recv;
668 
669 		dev_dbg(&perf->ntb->dev, "Message service initialized\n");
670 
671 		return 0;
672 	}
673 
674 	dev_dbg(&perf->ntb->dev, "Message service unsupported\n");
675 
676 	mask = GENMASK_ULL(perf->pcnt, 0);
677 	if (ntb_spad_count(perf->ntb) >= PERF_SPAD_CNT(perf->pcnt) &&
678 	    (ntb_db_valid_mask(perf->ntb) & mask) == mask) {
679 		perf->cmd_send = perf_spad_cmd_send;
680 		perf->cmd_recv = perf_spad_cmd_recv;
681 
682 		dev_dbg(&perf->ntb->dev, "Scratchpad service initialized\n");
683 
684 		return 0;
685 	}
686 
687 	dev_dbg(&perf->ntb->dev, "Scratchpad service unsupported\n");
688 
689 	dev_err(&perf->ntb->dev, "Command services unsupported\n");
690 
691 	return -EINVAL;
692 }
693 
694 static int perf_enable_service(struct perf_ctx *perf)
695 {
696 	u64 mask, incmd_bit;
697 	int ret, sidx, scnt;
698 
699 	mask = ntb_db_valid_mask(perf->ntb);
700 	(void)ntb_db_set_mask(perf->ntb, mask);
701 
702 	ret = ntb_set_ctx(perf->ntb, perf, &perf_ops);
703 	if (ret)
704 		return ret;
705 
706 	if (perf->cmd_send == perf_msg_cmd_send) {
707 		u64 inbits, outbits;
708 
709 		inbits = ntb_msg_inbits(perf->ntb);
710 		outbits = ntb_msg_outbits(perf->ntb);
711 		(void)ntb_msg_set_mask(perf->ntb, inbits | outbits);
712 
713 		incmd_bit = BIT_ULL(__ffs64(inbits));
714 		ret = ntb_msg_clear_mask(perf->ntb, incmd_bit);
715 
716 		dev_dbg(&perf->ntb->dev, "MSG sts unmasked %#llx\n", incmd_bit);
717 	} else {
718 		scnt = ntb_spad_count(perf->ntb);
719 		for (sidx = 0; sidx < scnt; sidx++)
720 			ntb_spad_write(perf->ntb, sidx, PERF_CMD_INVAL);
721 		incmd_bit = PERF_SPAD_NOTIFY(perf->gidx);
722 		ret = ntb_db_clear_mask(perf->ntb, incmd_bit);
723 
724 		dev_dbg(&perf->ntb->dev, "DB bits unmasked %#llx\n", incmd_bit);
725 	}
726 	if (ret) {
727 		ntb_clear_ctx(perf->ntb);
728 		return ret;
729 	}
730 
731 	ntb_link_enable(perf->ntb, NTB_SPEED_AUTO, NTB_WIDTH_AUTO);
732 	/* Might be not necessary */
733 	ntb_link_event(perf->ntb);
734 
735 	return 0;
736 }
737 
738 static void perf_disable_service(struct perf_ctx *perf)
739 {
740 	int pidx;
741 
742 	ntb_link_disable(perf->ntb);
743 
744 	if (perf->cmd_send == perf_msg_cmd_send) {
745 		u64 inbits;
746 
747 		inbits = ntb_msg_inbits(perf->ntb);
748 		(void)ntb_msg_set_mask(perf->ntb, inbits);
749 	} else {
750 		(void)ntb_db_set_mask(perf->ntb, PERF_SPAD_NOTIFY(perf->gidx));
751 	}
752 
753 	ntb_clear_ctx(perf->ntb);
754 
755 	for (pidx = 0; pidx < perf->pcnt; pidx++)
756 		perf_cmd_exec(&perf->peers[pidx], PERF_CMD_CLEAR);
757 
758 	for (pidx = 0; pidx < perf->pcnt; pidx++)
759 		flush_work(&perf->peers[pidx].service);
760 }
761 
762 /*==============================================================================
763  *                      Performance measuring work-thread
764  *==============================================================================
765  */
766 
767 static void perf_dma_copy_callback(void *data)
768 {
769 	struct perf_thread *pthr = data;
770 
771 	atomic_dec(&pthr->dma_sync);
772 	wake_up(&pthr->dma_wait);
773 }
774 
775 static int perf_copy_chunk(struct perf_thread *pthr,
776 			   void __iomem *dst, void *src, size_t len)
777 {
778 	struct dma_async_tx_descriptor *tx;
779 	struct dmaengine_unmap_data *unmap;
780 	struct device *dma_dev;
781 	int try = 0, ret = 0;
782 
783 	if (!use_dma) {
784 		memcpy_toio(dst, src, len);
785 		goto ret_check_tsync;
786 	}
787 
788 	dma_dev = pthr->dma_chan->device->dev;
789 
790 	if (!is_dma_copy_aligned(pthr->dma_chan->device, offset_in_page(src),
791 				 offset_in_page(dst), len))
792 		return -EIO;
793 
794 	unmap = dmaengine_get_unmap_data(dma_dev, 2, GFP_NOWAIT);
795 	if (!unmap)
796 		return -ENOMEM;
797 
798 	unmap->len = len;
799 	unmap->addr[0] = dma_map_page(dma_dev, virt_to_page(src),
800 		offset_in_page(src), len, DMA_TO_DEVICE);
801 	if (dma_mapping_error(dma_dev, unmap->addr[0])) {
802 		ret = -EIO;
803 		goto err_free_resource;
804 	}
805 	unmap->to_cnt = 1;
806 
807 	unmap->addr[1] = dma_map_page(dma_dev, virt_to_page(dst),
808 		offset_in_page(dst), len, DMA_FROM_DEVICE);
809 	if (dma_mapping_error(dma_dev, unmap->addr[1])) {
810 		ret = -EIO;
811 		goto err_free_resource;
812 	}
813 	unmap->from_cnt = 1;
814 
815 	do {
816 		tx = dmaengine_prep_dma_memcpy(pthr->dma_chan, unmap->addr[1],
817 			unmap->addr[0], len, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
818 		if (!tx)
819 			msleep(DMA_MDELAY);
820 	} while (!tx && (try++ < DMA_TRIES));
821 
822 	if (!tx) {
823 		ret = -EIO;
824 		goto err_free_resource;
825 	}
826 
827 	tx->callback = perf_dma_copy_callback;
828 	tx->callback_param = pthr;
829 	dma_set_unmap(tx, unmap);
830 
831 	if (dma_submit_error(dmaengine_submit(tx))) {
832 		dmaengine_unmap_put(unmap);
833 		goto err_free_resource;
834 	}
835 
836 	dmaengine_unmap_put(unmap);
837 
838 	atomic_inc(&pthr->dma_sync);
839 	dma_async_issue_pending(pthr->dma_chan);
840 
841 ret_check_tsync:
842 	return likely(atomic_read(&pthr->perf->tsync) > 0) ? 0 : -EINTR;
843 
844 err_free_resource:
845 	dmaengine_unmap_put(unmap);
846 
847 	return ret;
848 }
849 
850 static bool perf_dma_filter(struct dma_chan *chan, void *data)
851 {
852 	struct perf_ctx *perf = data;
853 	int node;
854 
855 	node = dev_to_node(&perf->ntb->dev);
856 
857 	return node == NUMA_NO_NODE || node == dev_to_node(chan->device->dev);
858 }
859 
860 static int perf_init_test(struct perf_thread *pthr)
861 {
862 	struct perf_ctx *perf = pthr->perf;
863 	dma_cap_mask_t dma_mask;
864 
865 	pthr->src = kmalloc_node(perf->test_peer->outbuf_size, GFP_KERNEL,
866 				 dev_to_node(&perf->ntb->dev));
867 	if (!pthr->src)
868 		return -ENOMEM;
869 
870 	get_random_bytes(pthr->src, perf->test_peer->outbuf_size);
871 
872 	if (!use_dma)
873 		return 0;
874 
875 	dma_cap_zero(dma_mask);
876 	dma_cap_set(DMA_MEMCPY, dma_mask);
877 	pthr->dma_chan = dma_request_channel(dma_mask, perf_dma_filter, perf);
878 	if (!pthr->dma_chan) {
879 		dev_err(&perf->ntb->dev, "%d: Failed to get DMA channel\n",
880 			pthr->tidx);
881 		atomic_dec(&perf->tsync);
882 		wake_up(&perf->twait);
883 		kfree(pthr->src);
884 		return -ENODEV;
885 	}
886 
887 	atomic_set(&pthr->dma_sync, 0);
888 
889 	return 0;
890 }
891 
892 static int perf_run_test(struct perf_thread *pthr)
893 {
894 	struct perf_peer *peer = pthr->perf->test_peer;
895 	struct perf_ctx *perf = pthr->perf;
896 	void __iomem *flt_dst, *bnd_dst;
897 	u64 total_size, chunk_size;
898 	void *flt_src;
899 	int ret = 0;
900 
901 	total_size = 1ULL << total_order;
902 	chunk_size = 1ULL << chunk_order;
903 	chunk_size = min_t(u64, peer->outbuf_size, chunk_size);
904 
905 	flt_src = pthr->src;
906 	bnd_dst = peer->outbuf + peer->outbuf_size;
907 	flt_dst = peer->outbuf;
908 
909 	pthr->duration = ktime_get();
910 
911 	/* Copied field is cleared on test launch stage */
912 	while (pthr->copied < total_size) {
913 		ret = perf_copy_chunk(pthr, flt_dst, flt_src, chunk_size);
914 		if (ret) {
915 			dev_err(&perf->ntb->dev, "%d: Got error %d on test\n",
916 				pthr->tidx, ret);
917 			return ret;
918 		}
919 
920 		pthr->copied += chunk_size;
921 
922 		flt_dst += chunk_size;
923 		flt_src += chunk_size;
924 		if (flt_dst >= bnd_dst || flt_dst < peer->outbuf) {
925 			flt_dst = peer->outbuf;
926 			flt_src = pthr->src;
927 		}
928 
929 		/* Give up CPU to give a chance for other threads to use it */
930 		schedule();
931 	}
932 
933 	return 0;
934 }
935 
936 static int perf_sync_test(struct perf_thread *pthr)
937 {
938 	struct perf_ctx *perf = pthr->perf;
939 
940 	if (!use_dma)
941 		goto no_dma_ret;
942 
943 	wait_event(pthr->dma_wait,
944 		   (atomic_read(&pthr->dma_sync) == 0 ||
945 		    atomic_read(&perf->tsync) < 0));
946 
947 	if (atomic_read(&perf->tsync) < 0)
948 		return -EINTR;
949 
950 no_dma_ret:
951 	pthr->duration = ktime_sub(ktime_get(), pthr->duration);
952 
953 	dev_dbg(&perf->ntb->dev, "%d: copied %llu bytes\n",
954 		pthr->tidx, pthr->copied);
955 
956 	dev_dbg(&perf->ntb->dev, "%d: lasted %llu usecs\n",
957 		pthr->tidx, ktime_to_us(pthr->duration));
958 
959 	dev_dbg(&perf->ntb->dev, "%d: %llu MBytes/s\n", pthr->tidx,
960 		div64_u64(pthr->copied, ktime_to_us(pthr->duration)));
961 
962 	return 0;
963 }
964 
965 static void perf_clear_test(struct perf_thread *pthr)
966 {
967 	struct perf_ctx *perf = pthr->perf;
968 
969 	if (!use_dma)
970 		goto no_dma_notify;
971 
972 	/*
973 	 * If test finished without errors, termination isn't needed.
974 	 * We call it anyway just to be sure of the transfers completion.
975 	 */
976 	(void)dmaengine_terminate_sync(pthr->dma_chan);
977 
978 	dma_release_channel(pthr->dma_chan);
979 
980 no_dma_notify:
981 	atomic_dec(&perf->tsync);
982 	wake_up(&perf->twait);
983 	kfree(pthr->src);
984 }
985 
986 static void perf_thread_work(struct work_struct *work)
987 {
988 	struct perf_thread *pthr = to_thread_work(work);
989 	int ret;
990 
991 	/*
992 	 * Perform stages in compliance with use_dma flag value.
993 	 * Test status is changed only if error happened, otherwise
994 	 * status -ENODATA is kept while test is on-fly. Results
995 	 * synchronization is performed only if test fininshed
996 	 * without an error or interruption.
997 	 */
998 	ret = perf_init_test(pthr);
999 	if (ret) {
1000 		pthr->status = ret;
1001 		return;
1002 	}
1003 
1004 	ret = perf_run_test(pthr);
1005 	if (ret) {
1006 		pthr->status = ret;
1007 		goto err_clear_test;
1008 	}
1009 
1010 	pthr->status = perf_sync_test(pthr);
1011 
1012 err_clear_test:
1013 	perf_clear_test(pthr);
1014 }
1015 
1016 static int perf_set_tcnt(struct perf_ctx *perf, u8 tcnt)
1017 {
1018 	if (tcnt == 0 || tcnt > MAX_THREADS_CNT)
1019 		return -EINVAL;
1020 
1021 	if (test_and_set_bit_lock(0, &perf->busy_flag))
1022 		return -EBUSY;
1023 
1024 	perf->tcnt = tcnt;
1025 
1026 	clear_bit_unlock(0, &perf->busy_flag);
1027 
1028 	return 0;
1029 }
1030 
1031 static void perf_terminate_test(struct perf_ctx *perf)
1032 {
1033 	int tidx;
1034 
1035 	atomic_set(&perf->tsync, -1);
1036 	wake_up(&perf->twait);
1037 
1038 	for (tidx = 0; tidx < MAX_THREADS_CNT; tidx++) {
1039 		wake_up(&perf->threads[tidx].dma_wait);
1040 		cancel_work_sync(&perf->threads[tidx].work);
1041 	}
1042 }
1043 
1044 static int perf_submit_test(struct perf_peer *peer)
1045 {
1046 	struct perf_ctx *perf = peer->perf;
1047 	struct perf_thread *pthr;
1048 	int tidx, ret;
1049 
1050 	if (!test_bit(PERF_STS_DONE, &peer->sts))
1051 		return -ENOLINK;
1052 
1053 	if (test_and_set_bit_lock(0, &perf->busy_flag))
1054 		return -EBUSY;
1055 
1056 	perf->test_peer = peer;
1057 	atomic_set(&perf->tsync, perf->tcnt);
1058 
1059 	for (tidx = 0; tidx < MAX_THREADS_CNT; tidx++) {
1060 		pthr = &perf->threads[tidx];
1061 
1062 		pthr->status = -ENODATA;
1063 		pthr->copied = 0;
1064 		pthr->duration = ktime_set(0, 0);
1065 		if (tidx < perf->tcnt)
1066 			(void)queue_work(perf_wq, &pthr->work);
1067 	}
1068 
1069 	ret = wait_event_interruptible(perf->twait,
1070 				       atomic_read(&perf->tsync) <= 0);
1071 	if (ret == -ERESTARTSYS) {
1072 		perf_terminate_test(perf);
1073 		ret = -EINTR;
1074 	}
1075 
1076 	clear_bit_unlock(0, &perf->busy_flag);
1077 
1078 	return ret;
1079 }
1080 
1081 static int perf_read_stats(struct perf_ctx *perf, char *buf,
1082 			   size_t size, ssize_t *pos)
1083 {
1084 	struct perf_thread *pthr;
1085 	int tidx;
1086 
1087 	if (test_and_set_bit_lock(0, &perf->busy_flag))
1088 		return -EBUSY;
1089 
1090 	(*pos) += scnprintf(buf + *pos, size - *pos,
1091 		"    Peer %d test statistics:\n", perf->test_peer->pidx);
1092 
1093 	for (tidx = 0; tidx < MAX_THREADS_CNT; tidx++) {
1094 		pthr = &perf->threads[tidx];
1095 
1096 		if (pthr->status == -ENODATA)
1097 			continue;
1098 
1099 		if (pthr->status) {
1100 			(*pos) += scnprintf(buf + *pos, size - *pos,
1101 				"%d: error status %d\n", tidx, pthr->status);
1102 			continue;
1103 		}
1104 
1105 		(*pos) += scnprintf(buf + *pos, size - *pos,
1106 			"%d: copied %llu bytes in %llu usecs, %llu MBytes/s\n",
1107 			tidx, pthr->copied, ktime_to_us(pthr->duration),
1108 			div64_u64(pthr->copied, ktime_to_us(pthr->duration)));
1109 	}
1110 
1111 	clear_bit_unlock(0, &perf->busy_flag);
1112 
1113 	return 0;
1114 }
1115 
1116 static void perf_init_threads(struct perf_ctx *perf)
1117 {
1118 	struct perf_thread *pthr;
1119 	int tidx;
1120 
1121 	perf->tcnt = DEF_THREADS_CNT;
1122 	perf->test_peer = &perf->peers[0];
1123 	init_waitqueue_head(&perf->twait);
1124 
1125 	for (tidx = 0; tidx < MAX_THREADS_CNT; tidx++) {
1126 		pthr = &perf->threads[tidx];
1127 
1128 		pthr->perf = perf;
1129 		pthr->tidx = tidx;
1130 		pthr->status = -ENODATA;
1131 		init_waitqueue_head(&pthr->dma_wait);
1132 		INIT_WORK(&pthr->work, perf_thread_work);
1133 	}
1134 }
1135 
1136 static void perf_clear_threads(struct perf_ctx *perf)
1137 {
1138 	perf_terminate_test(perf);
1139 }
1140 
1141 /*==============================================================================
1142  *                               DebugFS nodes
1143  *==============================================================================
1144  */
1145 
1146 static ssize_t perf_dbgfs_read_info(struct file *filep, char __user *ubuf,
1147 				    size_t size, loff_t *offp)
1148 {
1149 	struct perf_ctx *perf = filep->private_data;
1150 	struct perf_peer *peer;
1151 	size_t buf_size;
1152 	ssize_t pos = 0;
1153 	int ret, pidx;
1154 	char *buf;
1155 
1156 	buf_size = min_t(size_t, size, 0x1000U);
1157 
1158 	buf = kmalloc(buf_size, GFP_KERNEL);
1159 	if (!buf)
1160 		return -ENOMEM;
1161 
1162 	pos += scnprintf(buf + pos, buf_size - pos,
1163 		"    Performance measuring tool info:\n\n");
1164 
1165 	pos += scnprintf(buf + pos, buf_size - pos,
1166 		"Local port %d, Global index %d\n", ntb_port_number(perf->ntb),
1167 		perf->gidx);
1168 	pos += scnprintf(buf + pos, buf_size - pos, "Test status: ");
1169 	if (test_bit(0, &perf->busy_flag)) {
1170 		pos += scnprintf(buf + pos, buf_size - pos,
1171 			"on-fly with port %d (%d)\n",
1172 			ntb_peer_port_number(perf->ntb, perf->test_peer->pidx),
1173 			perf->test_peer->pidx);
1174 	} else {
1175 		pos += scnprintf(buf + pos, buf_size - pos, "idle\n");
1176 	}
1177 
1178 	for (pidx = 0; pidx < perf->pcnt; pidx++) {
1179 		peer = &perf->peers[pidx];
1180 
1181 		pos += scnprintf(buf + pos, buf_size - pos,
1182 			"Port %d (%d), Global index %d:\n",
1183 			ntb_peer_port_number(perf->ntb, peer->pidx), peer->pidx,
1184 			peer->gidx);
1185 
1186 		pos += scnprintf(buf + pos, buf_size - pos,
1187 			"\tLink status: %s\n",
1188 			test_bit(PERF_STS_LNKUP, &peer->sts) ? "up" : "down");
1189 
1190 		pos += scnprintf(buf + pos, buf_size - pos,
1191 			"\tOut buffer addr 0x%pK\n", peer->outbuf);
1192 
1193 		pos += scnprintf(buf + pos, buf_size - pos,
1194 			"\tOut buffer size %pa\n", &peer->outbuf_size);
1195 
1196 		pos += scnprintf(buf + pos, buf_size - pos,
1197 			"\tOut buffer xlat 0x%016llx[p]\n", peer->outbuf_xlat);
1198 
1199 		if (!peer->inbuf) {
1200 			pos += scnprintf(buf + pos, buf_size - pos,
1201 				"\tIn buffer addr: unallocated\n");
1202 			continue;
1203 		}
1204 
1205 		pos += scnprintf(buf + pos, buf_size - pos,
1206 			"\tIn buffer addr 0x%pK\n", peer->inbuf);
1207 
1208 		pos += scnprintf(buf + pos, buf_size - pos,
1209 			"\tIn buffer size %pa\n", &peer->inbuf_size);
1210 
1211 		pos += scnprintf(buf + pos, buf_size - pos,
1212 			"\tIn buffer xlat %pad[p]\n", &peer->inbuf_xlat);
1213 	}
1214 
1215 	ret = simple_read_from_buffer(ubuf, size, offp, buf, pos);
1216 	kfree(buf);
1217 
1218 	return ret;
1219 }
1220 
1221 static const struct file_operations perf_dbgfs_info = {
1222 	.open = simple_open,
1223 	.read = perf_dbgfs_read_info
1224 };
1225 
1226 static ssize_t perf_dbgfs_read_run(struct file *filep, char __user *ubuf,
1227 				   size_t size, loff_t *offp)
1228 {
1229 	struct perf_ctx *perf = filep->private_data;
1230 	ssize_t ret, pos = 0;
1231 	char *buf;
1232 
1233 	buf = kmalloc(PERF_BUF_LEN, GFP_KERNEL);
1234 	if (!buf)
1235 		return -ENOMEM;
1236 
1237 	ret = perf_read_stats(perf, buf, PERF_BUF_LEN, &pos);
1238 	if (ret)
1239 		goto err_free;
1240 
1241 	ret = simple_read_from_buffer(ubuf, size, offp, buf, pos);
1242 err_free:
1243 	kfree(buf);
1244 
1245 	return ret;
1246 }
1247 
1248 static ssize_t perf_dbgfs_write_run(struct file *filep, const char __user *ubuf,
1249 				    size_t size, loff_t *offp)
1250 {
1251 	struct perf_ctx *perf = filep->private_data;
1252 	struct perf_peer *peer;
1253 	int pidx, ret;
1254 
1255 	ret = kstrtoint_from_user(ubuf, size, 0, &pidx);
1256 	if (ret)
1257 		return ret;
1258 
1259 	if (pidx < 0 || pidx >= perf->pcnt)
1260 		return -EINVAL;
1261 
1262 	peer = &perf->peers[pidx];
1263 
1264 	ret = perf_submit_test(peer);
1265 	if (ret)
1266 		return ret;
1267 
1268 	return size;
1269 }
1270 
1271 static const struct file_operations perf_dbgfs_run = {
1272 	.open = simple_open,
1273 	.read = perf_dbgfs_read_run,
1274 	.write = perf_dbgfs_write_run
1275 };
1276 
1277 static ssize_t perf_dbgfs_read_tcnt(struct file *filep, char __user *ubuf,
1278 				    size_t size, loff_t *offp)
1279 {
1280 	struct perf_ctx *perf = filep->private_data;
1281 	char buf[8];
1282 	ssize_t pos;
1283 
1284 	pos = scnprintf(buf, sizeof(buf), "%hhu\n", perf->tcnt);
1285 
1286 	return simple_read_from_buffer(ubuf, size, offp, buf, pos);
1287 }
1288 
1289 static ssize_t perf_dbgfs_write_tcnt(struct file *filep,
1290 				     const char __user *ubuf,
1291 				     size_t size, loff_t *offp)
1292 {
1293 	struct perf_ctx *perf = filep->private_data;
1294 	int ret;
1295 	u8 val;
1296 
1297 	ret = kstrtou8_from_user(ubuf, size, 0, &val);
1298 	if (ret)
1299 		return ret;
1300 
1301 	ret = perf_set_tcnt(perf, val);
1302 	if (ret)
1303 		return ret;
1304 
1305 	return size;
1306 }
1307 
1308 static const struct file_operations perf_dbgfs_tcnt = {
1309 	.open = simple_open,
1310 	.read = perf_dbgfs_read_tcnt,
1311 	.write = perf_dbgfs_write_tcnt
1312 };
1313 
1314 static void perf_setup_dbgfs(struct perf_ctx *perf)
1315 {
1316 	struct pci_dev *pdev = perf->ntb->pdev;
1317 
1318 	perf->dbgfs_dir = debugfs_create_dir(pci_name(pdev), perf_dbgfs_topdir);
1319 	if (!perf->dbgfs_dir) {
1320 		dev_warn(&perf->ntb->dev, "DebugFS unsupported\n");
1321 		return;
1322 	}
1323 
1324 	debugfs_create_file("info", 0600, perf->dbgfs_dir, perf,
1325 			    &perf_dbgfs_info);
1326 
1327 	debugfs_create_file("run", 0600, perf->dbgfs_dir, perf,
1328 			    &perf_dbgfs_run);
1329 
1330 	debugfs_create_file("threads_count", 0600, perf->dbgfs_dir, perf,
1331 			    &perf_dbgfs_tcnt);
1332 
1333 	/* They are made read-only for test exec safety and integrity */
1334 	debugfs_create_u8("chunk_order", 0500, perf->dbgfs_dir, &chunk_order);
1335 
1336 	debugfs_create_u8("total_order", 0500, perf->dbgfs_dir, &total_order);
1337 
1338 	debugfs_create_bool("use_dma", 0500, perf->dbgfs_dir, &use_dma);
1339 }
1340 
1341 static void perf_clear_dbgfs(struct perf_ctx *perf)
1342 {
1343 	debugfs_remove_recursive(perf->dbgfs_dir);
1344 }
1345 
1346 /*==============================================================================
1347  *                        Basic driver initialization
1348  *==============================================================================
1349  */
1350 
1351 static struct perf_ctx *perf_create_data(struct ntb_dev *ntb)
1352 {
1353 	struct perf_ctx *perf;
1354 
1355 	perf = devm_kzalloc(&ntb->dev, sizeof(*perf), GFP_KERNEL);
1356 	if (!perf)
1357 		return ERR_PTR(-ENOMEM);
1358 
1359 	perf->pcnt = ntb_peer_port_count(ntb);
1360 	perf->peers = devm_kcalloc(&ntb->dev, perf->pcnt, sizeof(*perf->peers),
1361 				  GFP_KERNEL);
1362 	if (!perf->peers)
1363 		return ERR_PTR(-ENOMEM);
1364 
1365 	perf->ntb = ntb;
1366 
1367 	return perf;
1368 }
1369 
1370 static int perf_setup_peer_mw(struct perf_peer *peer)
1371 {
1372 	struct perf_ctx *perf = peer->perf;
1373 	phys_addr_t phys_addr;
1374 	int ret;
1375 
1376 	/* Get outbound MW parameters and map it */
1377 	ret = ntb_peer_mw_get_addr(perf->ntb, peer->gidx, &phys_addr,
1378 				   &peer->outbuf_size);
1379 	if (ret)
1380 		return ret;
1381 
1382 	peer->outbuf = devm_ioremap_wc(&perf->ntb->dev, phys_addr,
1383 					peer->outbuf_size);
1384 	if (!peer->outbuf)
1385 		return -ENOMEM;
1386 
1387 	if (max_mw_size && peer->outbuf_size > max_mw_size) {
1388 		peer->outbuf_size = max_mw_size;
1389 		dev_warn(&peer->perf->ntb->dev,
1390 			"Peer %d outbuf reduced to %pa\n", peer->pidx,
1391 			&peer->outbuf_size);
1392 	}
1393 
1394 	return 0;
1395 }
1396 
1397 static int perf_init_peers(struct perf_ctx *perf)
1398 {
1399 	struct perf_peer *peer;
1400 	int pidx, lport, ret;
1401 
1402 	lport = ntb_port_number(perf->ntb);
1403 	perf->gidx = -1;
1404 	for (pidx = 0; pidx < perf->pcnt; pidx++) {
1405 		peer = &perf->peers[pidx];
1406 
1407 		peer->perf = perf;
1408 		peer->pidx = pidx;
1409 		if (lport < ntb_peer_port_number(perf->ntb, pidx)) {
1410 			if (perf->gidx == -1)
1411 				perf->gidx = pidx;
1412 			peer->gidx = pidx + 1;
1413 		} else {
1414 			peer->gidx = pidx;
1415 		}
1416 		INIT_WORK(&peer->service, perf_service_work);
1417 	}
1418 	if (perf->gidx == -1)
1419 		perf->gidx = pidx;
1420 
1421 	for (pidx = 0; pidx < perf->pcnt; pidx++) {
1422 		ret = perf_setup_peer_mw(&perf->peers[pidx]);
1423 		if (ret)
1424 			return ret;
1425 	}
1426 
1427 	dev_dbg(&perf->ntb->dev, "Global port index %d\n", perf->gidx);
1428 
1429 	return 0;
1430 }
1431 
1432 static int perf_probe(struct ntb_client *client, struct ntb_dev *ntb)
1433 {
1434 	struct perf_ctx *perf;
1435 	int ret;
1436 
1437 	perf = perf_create_data(ntb);
1438 	if (IS_ERR(perf))
1439 		return PTR_ERR(perf);
1440 
1441 	ret = perf_init_peers(perf);
1442 	if (ret)
1443 		return ret;
1444 
1445 	perf_init_threads(perf);
1446 
1447 	ret = perf_init_service(perf);
1448 	if (ret)
1449 		return ret;
1450 
1451 	ret = perf_enable_service(perf);
1452 	if (ret)
1453 		return ret;
1454 
1455 	perf_setup_dbgfs(perf);
1456 
1457 	return 0;
1458 }
1459 
1460 static void perf_remove(struct ntb_client *client, struct ntb_dev *ntb)
1461 {
1462 	struct perf_ctx *perf = ntb->ctx;
1463 
1464 	perf_clear_dbgfs(perf);
1465 
1466 	perf_disable_service(perf);
1467 
1468 	perf_clear_threads(perf);
1469 }
1470 
1471 static struct ntb_client perf_client = {
1472 	.ops = {
1473 		.probe = perf_probe,
1474 		.remove = perf_remove
1475 	}
1476 };
1477 
1478 static int __init perf_init(void)
1479 {
1480 	int ret;
1481 
1482 	if (chunk_order > MAX_CHUNK_ORDER) {
1483 		chunk_order = MAX_CHUNK_ORDER;
1484 		pr_info("Chunk order reduced to %hhu\n", chunk_order);
1485 	}
1486 
1487 	if (total_order < chunk_order) {
1488 		total_order = chunk_order;
1489 		pr_info("Total data order reduced to %hhu\n", total_order);
1490 	}
1491 
1492 	perf_wq = alloc_workqueue("perf_wq", WQ_UNBOUND | WQ_SYSFS, 0);
1493 	if (!perf_wq)
1494 		return -ENOMEM;
1495 
1496 	if (debugfs_initialized())
1497 		perf_dbgfs_topdir = debugfs_create_dir(KBUILD_MODNAME, NULL);
1498 
1499 	ret = ntb_register_client(&perf_client);
1500 	if (ret) {
1501 		debugfs_remove_recursive(perf_dbgfs_topdir);
1502 		destroy_workqueue(perf_wq);
1503 	}
1504 
1505 	return ret;
1506 }
1507 module_init(perf_init);
1508 
1509 static void __exit perf_exit(void)
1510 {
1511 	ntb_unregister_client(&perf_client);
1512 	debugfs_remove_recursive(perf_dbgfs_topdir);
1513 	destroy_workqueue(perf_wq);
1514 }
1515 module_exit(perf_exit);
1516 
1517