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docs: fix Co-Developed-by docs
[linux/fpc-iii.git] / drivers / ntb / ntb_transport.c
blob3bfdb4562408879fd04f340b05e84673c4da2232
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) 2012 Intel Corporation. All rights reserved.
8 * Copyright (C) 2015 EMC Corporation. 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) 2012 Intel Corporation. All rights reserved.
17 * Copyright (C) 2015 EMC Corporation. 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 Transport Linux driver
46 *
47 * Contact Information:
48 * Jon Mason <jon.mason@intel.com>
49 */
50 #include <linux/debugfs.h>
51 #include <linux/delay.h>
52 #include <linux/dmaengine.h>
53 #include <linux/dma-mapping.h>
54 #include <linux/errno.h>
55 #include <linux/export.h>
56 #include <linux/interrupt.h>
57 #include <linux/module.h>
58 #include <linux/pci.h>
59 #include <linux/slab.h>
60 #include <linux/types.h>
61 #include <linux/uaccess.h>
62 #include "linux/ntb.h"
63 #include "linux/ntb_transport.h"
64
65 #define NTB_TRANSPORT_VERSION 4
66 #define NTB_TRANSPORT_VER "4"
67 #define NTB_TRANSPORT_NAME "ntb_transport"
68 #define NTB_TRANSPORT_DESC "Software Queue-Pair Transport over NTB"
69 #define NTB_TRANSPORT_MIN_SPADS (MW0_SZ_HIGH + 2)
70
71 MODULE_DESCRIPTION(NTB_TRANSPORT_DESC);
72 MODULE_VERSION(NTB_TRANSPORT_VER);
73 MODULE_LICENSE("Dual BSD/GPL");
74 MODULE_AUTHOR("Intel Corporation");
75
76 static unsigned long max_mw_size;
77 module_param(max_mw_size, ulong, 0644);
78 MODULE_PARM_DESC(max_mw_size, "Limit size of large memory windows");
79
80 static unsigned int transport_mtu = 0x10000;
81 module_param(transport_mtu, uint, 0644);
82 MODULE_PARM_DESC(transport_mtu, "Maximum size of NTB transport packets");
83
84 static unsigned char max_num_clients;
85 module_param(max_num_clients, byte, 0644);
86 MODULE_PARM_DESC(max_num_clients, "Maximum number of NTB transport clients");
87
88 static unsigned int copy_bytes = 1024;
89 module_param(copy_bytes, uint, 0644);
90 MODULE_PARM_DESC(copy_bytes, "Threshold under which NTB will use the CPU to copy instead of DMA");
91
92 static bool use_dma;
93 module_param(use_dma, bool, 0644);
94 MODULE_PARM_DESC(use_dma, "Use DMA engine to perform large data copy");
95
96 static struct dentry *nt_debugfs_dir;
97
98 /* Only two-ports NTB devices are supported */
99 #define PIDX NTB_DEF_PEER_IDX
100
101 struct ntb_queue_entry {
102 /* ntb_queue list reference */
103 struct list_head entry;
104 /* pointers to data to be transferred */
105 void *cb_data;
106 void *buf;
107 unsigned int len;
108 unsigned int flags;
109 int retries;
110 int errors;
111 unsigned int tx_index;
112 unsigned int rx_index;
113
114 struct ntb_transport_qp *qp;
115 union {
116 struct ntb_payload_header __iomem *tx_hdr;
117 struct ntb_payload_header *rx_hdr;
118 };
119 };
120
121 struct ntb_rx_info {
122 unsigned int entry;
123 };
124
125 struct ntb_transport_qp {
126 struct ntb_transport_ctx *transport;
127 struct ntb_dev *ndev;
128 void *cb_data;
129 struct dma_chan *tx_dma_chan;
130 struct dma_chan *rx_dma_chan;
131
132 bool client_ready;
133 bool link_is_up;
134 bool active;
135
136 u8 qp_num; /* Only 64 QP's are allowed. 0-63 */
137 u64 qp_bit;
138
139 struct ntb_rx_info __iomem *rx_info;
140 struct ntb_rx_info *remote_rx_info;
141
142 void (*tx_handler)(struct ntb_transport_qp *qp, void *qp_data,
143 void *data, int len);
144 struct list_head tx_free_q;
145 spinlock_t ntb_tx_free_q_lock;
146 void __iomem *tx_mw;
147 dma_addr_t tx_mw_phys;
148 unsigned int tx_index;
149 unsigned int tx_max_entry;
150 unsigned int tx_max_frame;
151
152 void (*rx_handler)(struct ntb_transport_qp *qp, void *qp_data,
153 void *data, int len);
154 struct list_head rx_post_q;
155 struct list_head rx_pend_q;
156 struct list_head rx_free_q;
157 /* ntb_rx_q_lock: synchronize access to rx_XXXX_q */
158 spinlock_t ntb_rx_q_lock;
159 void *rx_buff;
160 unsigned int rx_index;
161 unsigned int rx_max_entry;
162 unsigned int rx_max_frame;
163 unsigned int rx_alloc_entry;
164 dma_cookie_t last_cookie;
165 struct tasklet_struct rxc_db_work;
166
167 void (*event_handler)(void *data, int status);
168 struct delayed_work link_work;
169 struct work_struct link_cleanup;
170
171 struct dentry *debugfs_dir;
172 struct dentry *debugfs_stats;
173
174 /* Stats */
175 u64 rx_bytes;
176 u64 rx_pkts;
177 u64 rx_ring_empty;
178 u64 rx_err_no_buf;
179 u64 rx_err_oflow;
180 u64 rx_err_ver;
181 u64 rx_memcpy;
182 u64 rx_async;
183 u64 tx_bytes;
184 u64 tx_pkts;
185 u64 tx_ring_full;
186 u64 tx_err_no_buf;
187 u64 tx_memcpy;
188 u64 tx_async;
189 };
190
191 struct ntb_transport_mw {
192 phys_addr_t phys_addr;
193 resource_size_t phys_size;
194 void __iomem *vbase;
195 size_t xlat_size;
196 size_t buff_size;
197 size_t alloc_size;
198 void *alloc_addr;
199 void *virt_addr;
200 dma_addr_t dma_addr;
201 };
202
203 struct ntb_transport_client_dev {
204 struct list_head entry;
205 struct ntb_transport_ctx *nt;
206 struct device dev;
207 };
208
209 struct ntb_transport_ctx {
210 struct list_head entry;
211 struct list_head client_devs;
212
213 struct ntb_dev *ndev;
214
215 struct ntb_transport_mw *mw_vec;
216 struct ntb_transport_qp *qp_vec;
217 unsigned int mw_count;
218 unsigned int qp_count;
219 u64 qp_bitmap;
220 u64 qp_bitmap_free;
221
222 bool link_is_up;
223 struct delayed_work link_work;
224 struct work_struct link_cleanup;
225
226 struct dentry *debugfs_node_dir;
227 };
228
229 enum {
230 DESC_DONE_FLAG = BIT(0),
231 LINK_DOWN_FLAG = BIT(1),
232 };
233
234 struct ntb_payload_header {
235 unsigned int ver;
236 unsigned int len;
237 unsigned int flags;
238 };
239
240 enum {
241 VERSION = 0,
242 QP_LINKS,
243 NUM_QPS,
244 NUM_MWS,
245 MW0_SZ_HIGH,
246 MW0_SZ_LOW,
247 };
248
249 #define dev_client_dev(__dev) \
250 container_of((__dev), struct ntb_transport_client_dev, dev)
251
252 #define drv_client(__drv) \
253 container_of((__drv), struct ntb_transport_client, driver)
254
255 #define QP_TO_MW(nt, qp) ((qp) % nt->mw_count)
256 #define NTB_QP_DEF_NUM_ENTRIES 100
257 #define NTB_LINK_DOWN_TIMEOUT 10
258
259 static void ntb_transport_rxc_db(unsigned long data);
260 static const struct ntb_ctx_ops ntb_transport_ops;
261 static struct ntb_client ntb_transport_client;
262 static int ntb_async_tx_submit(struct ntb_transport_qp *qp,
263 struct ntb_queue_entry *entry);
264 static void ntb_memcpy_tx(struct ntb_queue_entry *entry, void __iomem *offset);
265 static int ntb_async_rx_submit(struct ntb_queue_entry *entry, void *offset);
266 static void ntb_memcpy_rx(struct ntb_queue_entry *entry, void *offset);
267
268
269 static int ntb_transport_bus_match(struct device *dev,
270 struct device_driver *drv)
271 {
272 return !strncmp(dev_name(dev), drv->name, strlen(drv->name));
273 }
274
275 static int ntb_transport_bus_probe(struct device *dev)
276 {
277 const struct ntb_transport_client *client;
278 int rc = -EINVAL;
279
280 get_device(dev);
281
282 client = drv_client(dev->driver);
283 rc = client->probe(dev);
284 if (rc)
285 put_device(dev);
286
287 return rc;
288 }
289
290 static int ntb_transport_bus_remove(struct device *dev)
291 {
292 const struct ntb_transport_client *client;
293
294 client = drv_client(dev->driver);
295 client->remove(dev);
296
297 put_device(dev);
298
299 return 0;
300 }
301
302 static struct bus_type ntb_transport_bus = {
303 .name = "ntb_transport",
304 .match = ntb_transport_bus_match,
305 .probe = ntb_transport_bus_probe,
306 .remove = ntb_transport_bus_remove,
307 };
308
309 static LIST_HEAD(ntb_transport_list);
310
311 static int ntb_bus_init(struct ntb_transport_ctx *nt)
312 {
313 list_add_tail(&nt->entry, &ntb_transport_list);
314 return 0;
315 }
316
317 static void ntb_bus_remove(struct ntb_transport_ctx *nt)
318 {
319 struct ntb_transport_client_dev *client_dev, *cd;
320
321 list_for_each_entry_safe(client_dev, cd, &nt->client_devs, entry) {
322 dev_err(client_dev->dev.parent, "%s still attached to bus, removing\n",
323 dev_name(&client_dev->dev));
324 list_del(&client_dev->entry);
325 device_unregister(&client_dev->dev);
326 }
327
328 list_del(&nt->entry);
329 }
330
331 static void ntb_transport_client_release(struct device *dev)
332 {
333 struct ntb_transport_client_dev *client_dev;
334
335 client_dev = dev_client_dev(dev);
336 kfree(client_dev);
337 }
338
339 /**
340 * ntb_transport_unregister_client_dev - Unregister NTB client device
341 * @device_name: Name of NTB client device
342 *
343 * Unregister an NTB client device with the NTB transport layer
344 */
345 void ntb_transport_unregister_client_dev(char *device_name)
346 {
347 struct ntb_transport_client_dev *client, *cd;
348 struct ntb_transport_ctx *nt;
349
350 list_for_each_entry(nt, &ntb_transport_list, entry)
351 list_for_each_entry_safe(client, cd, &nt->client_devs, entry)
352 if (!strncmp(dev_name(&client->dev), device_name,
353 strlen(device_name))) {
354 list_del(&client->entry);
355 device_unregister(&client->dev);
356 }
357 }
358 EXPORT_SYMBOL_GPL(ntb_transport_unregister_client_dev);
359
360 /**
361 * ntb_transport_register_client_dev - Register NTB client device
362 * @device_name: Name of NTB client device
363 *
364 * Register an NTB client device with the NTB transport layer
365 */
366 int ntb_transport_register_client_dev(char *device_name)
367 {
368 struct ntb_transport_client_dev *client_dev;
369 struct ntb_transport_ctx *nt;
370 int node;
371 int rc, i = 0;
372
373 if (list_empty(&ntb_transport_list))
374 return -ENODEV;
375
376 list_for_each_entry(nt, &ntb_transport_list, entry) {
377 struct device *dev;
378
379 node = dev_to_node(&nt->ndev->dev);
380
381 client_dev = kzalloc_node(sizeof(*client_dev),
382 GFP_KERNEL, node);
383 if (!client_dev) {
384 rc = -ENOMEM;
385 goto err;
386 }
387
388 dev = &client_dev->dev;
389
390 /* setup and register client devices */
391 dev_set_name(dev, "%s%d", device_name, i);
392 dev->bus = &ntb_transport_bus;
393 dev->release = ntb_transport_client_release;
394 dev->parent = &nt->ndev->dev;
395
396 rc = device_register(dev);
397 if (rc) {
398 kfree(client_dev);
399 goto err;
400 }
401
402 list_add_tail(&client_dev->entry, &nt->client_devs);
403 i++;
404 }
405
406 return 0;
407
408 err:
409 ntb_transport_unregister_client_dev(device_name);
410
411 return rc;
412 }
413 EXPORT_SYMBOL_GPL(ntb_transport_register_client_dev);
414
415 /**
416 * ntb_transport_register_client - Register NTB client driver
417 * @drv: NTB client driver to be registered
418 *
419 * Register an NTB client driver with the NTB transport layer
420 *
421 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
422 */
423 int ntb_transport_register_client(struct ntb_transport_client *drv)
424 {
425 drv->driver.bus = &ntb_transport_bus;
426
427 if (list_empty(&ntb_transport_list))
428 return -ENODEV;
429
430 return driver_register(&drv->driver);
431 }
432 EXPORT_SYMBOL_GPL(ntb_transport_register_client);
433
434 /**
435 * ntb_transport_unregister_client - Unregister NTB client driver
436 * @drv: NTB client driver to be unregistered
437 *
438 * Unregister an NTB client driver with the NTB transport layer
439 *
440 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
441 */
442 void ntb_transport_unregister_client(struct ntb_transport_client *drv)
443 {
444 driver_unregister(&drv->driver);
445 }
446 EXPORT_SYMBOL_GPL(ntb_transport_unregister_client);
447
448 static ssize_t debugfs_read(struct file *filp, char __user *ubuf, size_t count,
449 loff_t *offp)
450 {
451 struct ntb_transport_qp *qp;
452 char *buf;
453 ssize_t ret, out_offset, out_count;
454
455 qp = filp->private_data;
456
457 if (!qp || !qp->link_is_up)
458 return 0;
459
460 out_count = 1000;
461
462 buf = kmalloc(out_count, GFP_KERNEL);
463 if (!buf)
464 return -ENOMEM;
465
466 out_offset = 0;
467 out_offset += snprintf(buf + out_offset, out_count - out_offset,
468 "\nNTB QP stats:\n\n");
469 out_offset += snprintf(buf + out_offset, out_count - out_offset,
470 "rx_bytes - \t%llu\n", qp->rx_bytes);
471 out_offset += snprintf(buf + out_offset, out_count - out_offset,
472 "rx_pkts - \t%llu\n", qp->rx_pkts);
473 out_offset += snprintf(buf + out_offset, out_count - out_offset,
474 "rx_memcpy - \t%llu\n", qp->rx_memcpy);
475 out_offset += snprintf(buf + out_offset, out_count - out_offset,
476 "rx_async - \t%llu\n", qp->rx_async);
477 out_offset += snprintf(buf + out_offset, out_count - out_offset,
478 "rx_ring_empty - %llu\n", qp->rx_ring_empty);
479 out_offset += snprintf(buf + out_offset, out_count - out_offset,
480 "rx_err_no_buf - %llu\n", qp->rx_err_no_buf);
481 out_offset += snprintf(buf + out_offset, out_count - out_offset,
482 "rx_err_oflow - \t%llu\n", qp->rx_err_oflow);
483 out_offset += snprintf(buf + out_offset, out_count - out_offset,
484 "rx_err_ver - \t%llu\n", qp->rx_err_ver);
485 out_offset += snprintf(buf + out_offset, out_count - out_offset,
486 "rx_buff - \t0x%p\n", qp->rx_buff);
487 out_offset += snprintf(buf + out_offset, out_count - out_offset,
488 "rx_index - \t%u\n", qp->rx_index);
489 out_offset += snprintf(buf + out_offset, out_count - out_offset,
490 "rx_max_entry - \t%u\n", qp->rx_max_entry);
491 out_offset += snprintf(buf + out_offset, out_count - out_offset,
492 "rx_alloc_entry - \t%u\n\n", qp->rx_alloc_entry);
493
494 out_offset += snprintf(buf + out_offset, out_count - out_offset,
495 "tx_bytes - \t%llu\n", qp->tx_bytes);
496 out_offset += snprintf(buf + out_offset, out_count - out_offset,
497 "tx_pkts - \t%llu\n", qp->tx_pkts);
498 out_offset += snprintf(buf + out_offset, out_count - out_offset,
499 "tx_memcpy - \t%llu\n", qp->tx_memcpy);
500 out_offset += snprintf(buf + out_offset, out_count - out_offset,
501 "tx_async - \t%llu\n", qp->tx_async);
502 out_offset += snprintf(buf + out_offset, out_count - out_offset,
503 "tx_ring_full - \t%llu\n", qp->tx_ring_full);
504 out_offset += snprintf(buf + out_offset, out_count - out_offset,
505 "tx_err_no_buf - %llu\n", qp->tx_err_no_buf);
506 out_offset += snprintf(buf + out_offset, out_count - out_offset,
507 "tx_mw - \t0x%p\n", qp->tx_mw);
508 out_offset += snprintf(buf + out_offset, out_count - out_offset,
509 "tx_index (H) - \t%u\n", qp->tx_index);
510 out_offset += snprintf(buf + out_offset, out_count - out_offset,
511 "RRI (T) - \t%u\n",
512 qp->remote_rx_info->entry);
513 out_offset += snprintf(buf + out_offset, out_count - out_offset,
514 "tx_max_entry - \t%u\n", qp->tx_max_entry);
515 out_offset += snprintf(buf + out_offset, out_count - out_offset,
516 "free tx - \t%u\n",
517 ntb_transport_tx_free_entry(qp));
518
519 out_offset += snprintf(buf + out_offset, out_count - out_offset,
520 "\n");
521 out_offset += snprintf(buf + out_offset, out_count - out_offset,
522 "Using TX DMA - \t%s\n",
523 qp->tx_dma_chan ? "Yes" : "No");
524 out_offset += snprintf(buf + out_offset, out_count - out_offset,
525 "Using RX DMA - \t%s\n",
526 qp->rx_dma_chan ? "Yes" : "No");
527 out_offset += snprintf(buf + out_offset, out_count - out_offset,
528 "QP Link - \t%s\n",
529 qp->link_is_up ? "Up" : "Down");
530 out_offset += snprintf(buf + out_offset, out_count - out_offset,
531 "\n");
532
533 if (out_offset > out_count)
534 out_offset = out_count;
535
536 ret = simple_read_from_buffer(ubuf, count, offp, buf, out_offset);
537 kfree(buf);
538 return ret;
539 }
540
541 static const struct file_operations ntb_qp_debugfs_stats = {
542 .owner = THIS_MODULE,
543 .open = simple_open,
544 .read = debugfs_read,
545 };
546
547 static void ntb_list_add(spinlock_t *lock, struct list_head *entry,
548 struct list_head *list)
549 {
550 unsigned long flags;
551
552 spin_lock_irqsave(lock, flags);
553 list_add_tail(entry, list);
554 spin_unlock_irqrestore(lock, flags);
555 }
556
557 static struct ntb_queue_entry *ntb_list_rm(spinlock_t *lock,
558 struct list_head *list)
559 {
560 struct ntb_queue_entry *entry;
561 unsigned long flags;
562
563 spin_lock_irqsave(lock, flags);
564 if (list_empty(list)) {
565 entry = NULL;
566 goto out;
567 }
568 entry = list_first_entry(list, struct ntb_queue_entry, entry);
569 list_del(&entry->entry);
570
571 out:
572 spin_unlock_irqrestore(lock, flags);
573
574 return entry;
575 }
576
577 static struct ntb_queue_entry *ntb_list_mv(spinlock_t *lock,
578 struct list_head *list,
579 struct list_head *to_list)
580 {
581 struct ntb_queue_entry *entry;
582 unsigned long flags;
583
584 spin_lock_irqsave(lock, flags);
585
586 if (list_empty(list)) {
587 entry = NULL;
588 } else {
589 entry = list_first_entry(list, struct ntb_queue_entry, entry);
590 list_move_tail(&entry->entry, to_list);
591 }
592
593 spin_unlock_irqrestore(lock, flags);
594
595 return entry;
596 }
597
598 static int ntb_transport_setup_qp_mw(struct ntb_transport_ctx *nt,
599 unsigned int qp_num)
600 {
601 struct ntb_transport_qp *qp = &nt->qp_vec[qp_num];
602 struct ntb_transport_mw *mw;
603 struct ntb_dev *ndev = nt->ndev;
604 struct ntb_queue_entry *entry;
605 unsigned int rx_size, num_qps_mw;
606 unsigned int mw_num, mw_count, qp_count;
607 unsigned int i;
608 int node;
609
610 mw_count = nt->mw_count;
611 qp_count = nt->qp_count;
612
613 mw_num = QP_TO_MW(nt, qp_num);
614 mw = &nt->mw_vec[mw_num];
615
616 if (!mw->virt_addr)
617 return -ENOMEM;
618
619 if (mw_num < qp_count % mw_count)
620 num_qps_mw = qp_count / mw_count + 1;
621 else
622 num_qps_mw = qp_count / mw_count;
623
624 rx_size = (unsigned int)mw->xlat_size / num_qps_mw;
625 qp->rx_buff = mw->virt_addr + rx_size * (qp_num / mw_count);
626 rx_size -= sizeof(struct ntb_rx_info);
627
628 qp->remote_rx_info = qp->rx_buff + rx_size;
629
630 /* Due to housekeeping, there must be atleast 2 buffs */
631 qp->rx_max_frame = min(transport_mtu, rx_size / 2);
632 qp->rx_max_entry = rx_size / qp->rx_max_frame;
633 qp->rx_index = 0;
634
635 /*
636 * Checking to see if we have more entries than the default.
637 * We should add additional entries if that is the case so we
638 * can be in sync with the transport frames.
639 */
640 node = dev_to_node(&ndev->dev);
641 for (i = qp->rx_alloc_entry; i < qp->rx_max_entry; i++) {
642 entry = kzalloc_node(sizeof(*entry), GFP_KERNEL, node);
643 if (!entry)
644 return -ENOMEM;
645
646 entry->qp = qp;
647 ntb_list_add(&qp->ntb_rx_q_lock, &entry->entry,
648 &qp->rx_free_q);
649 qp->rx_alloc_entry++;
650 }
651
652 qp->remote_rx_info->entry = qp->rx_max_entry - 1;
653
654 /* setup the hdr offsets with 0's */
655 for (i = 0; i < qp->rx_max_entry; i++) {
656 void *offset = (qp->rx_buff + qp->rx_max_frame * (i + 1) -
657 sizeof(struct ntb_payload_header));
658 memset(offset, 0, sizeof(struct ntb_payload_header));
659 }
660
661 qp->rx_pkts = 0;
662 qp->tx_pkts = 0;
663 qp->tx_index = 0;
664
665 return 0;
666 }
667
668 static void ntb_free_mw(struct ntb_transport_ctx *nt, int num_mw)
669 {
670 struct ntb_transport_mw *mw = &nt->mw_vec[num_mw];
671 struct pci_dev *pdev = nt->ndev->pdev;
672
673 if (!mw->virt_addr)
674 return;
675
676 ntb_mw_clear_trans(nt->ndev, PIDX, num_mw);
677 dma_free_coherent(&pdev->dev, mw->alloc_size,
678 mw->alloc_addr, mw->dma_addr);
679 mw->xlat_size = 0;
680 mw->buff_size = 0;
681 mw->alloc_size = 0;
682 mw->alloc_addr = NULL;
683 mw->virt_addr = NULL;
684 }
685
686 static int ntb_alloc_mw_buffer(struct ntb_transport_mw *mw,
687 struct device *dma_dev, size_t align)
688 {
689 dma_addr_t dma_addr;
690 void *alloc_addr, *virt_addr;
691 int rc;
692
693 alloc_addr = dma_alloc_coherent(dma_dev, mw->alloc_size,
694 &dma_addr, GFP_KERNEL);
695 if (!alloc_addr) {
696 dev_err(dma_dev, "Unable to alloc MW buff of size %zu\n",
697 mw->alloc_size);
698 return -ENOMEM;
699 }
700 virt_addr = alloc_addr;
701
702 /*
703 * we must ensure that the memory address allocated is BAR size
704 * aligned in order for the XLAT register to take the value. This
705 * is a requirement of the hardware. It is recommended to setup CMA
706 * for BAR sizes equal or greater than 4MB.
707 */
708 if (!IS_ALIGNED(dma_addr, align)) {
709 if (mw->alloc_size > mw->buff_size) {
710 virt_addr = PTR_ALIGN(alloc_addr, align);
711 dma_addr = ALIGN(dma_addr, align);
712 } else {
713 rc = -ENOMEM;
714 goto err;
715 }
716 }
717
718 mw->alloc_addr = alloc_addr;
719 mw->virt_addr = virt_addr;
720 mw->dma_addr = dma_addr;
721
722 return 0;
723
724 err:
725 dma_free_coherent(dma_dev, mw->alloc_size, alloc_addr, dma_addr);
726
727 return rc;
728 }
729
730 static int ntb_set_mw(struct ntb_transport_ctx *nt, int num_mw,
731 resource_size_t size)
732 {
733 struct ntb_transport_mw *mw = &nt->mw_vec[num_mw];
734 struct pci_dev *pdev = nt->ndev->pdev;
735 size_t xlat_size, buff_size;
736 resource_size_t xlat_align;
737 resource_size_t xlat_align_size;
738 int rc;
739
740 if (!size)
741 return -EINVAL;
742
743 rc = ntb_mw_get_align(nt->ndev, PIDX, num_mw, &xlat_align,
744 &xlat_align_size, NULL);
745 if (rc)
746 return rc;
747
748 xlat_size = round_up(size, xlat_align_size);
749 buff_size = round_up(size, xlat_align);
750
751 /* No need to re-setup */
752 if (mw->xlat_size == xlat_size)
753 return 0;
754
755 if (mw->buff_size)
756 ntb_free_mw(nt, num_mw);
757
758 /* Alloc memory for receiving data. Must be aligned */
759 mw->xlat_size = xlat_size;
760 mw->buff_size = buff_size;
761 mw->alloc_size = buff_size;
762
763 rc = ntb_alloc_mw_buffer(mw, &pdev->dev, xlat_align);
764 if (rc) {
765 mw->alloc_size *= 2;
766 rc = ntb_alloc_mw_buffer(mw, &pdev->dev, xlat_align);
767 if (rc) {
768 dev_err(&pdev->dev,
769 "Unable to alloc aligned MW buff\n");
770 mw->xlat_size = 0;
771 mw->buff_size = 0;
772 mw->alloc_size = 0;
773 return rc;
774 }
775 }
776
777 /* Notify HW the memory location of the receive buffer */
778 rc = ntb_mw_set_trans(nt->ndev, PIDX, num_mw, mw->dma_addr,
779 mw->xlat_size);
780 if (rc) {
781 dev_err(&pdev->dev, "Unable to set mw%d translation", num_mw);
782 ntb_free_mw(nt, num_mw);
783 return -EIO;
784 }
785
786 return 0;
787 }
788
789 static void ntb_qp_link_down_reset(struct ntb_transport_qp *qp)
790 {
791 qp->link_is_up = false;
792 qp->active = false;
793
794 qp->tx_index = 0;
795 qp->rx_index = 0;
796 qp->rx_bytes = 0;
797 qp->rx_pkts = 0;
798 qp->rx_ring_empty = 0;
799 qp->rx_err_no_buf = 0;
800 qp->rx_err_oflow = 0;
801 qp->rx_err_ver = 0;
802 qp->rx_memcpy = 0;
803 qp->rx_async = 0;
804 qp->tx_bytes = 0;
805 qp->tx_pkts = 0;
806 qp->tx_ring_full = 0;
807 qp->tx_err_no_buf = 0;
808 qp->tx_memcpy = 0;
809 qp->tx_async = 0;
810 }
811
812 static void ntb_qp_link_cleanup(struct ntb_transport_qp *qp)
813 {
814 struct ntb_transport_ctx *nt = qp->transport;
815 struct pci_dev *pdev = nt->ndev->pdev;
816
817 dev_info(&pdev->dev, "qp %d: Link Cleanup\n", qp->qp_num);
818
819 cancel_delayed_work_sync(&qp->link_work);
820 ntb_qp_link_down_reset(qp);
821
822 if (qp->event_handler)
823 qp->event_handler(qp->cb_data, qp->link_is_up);
824 }
825
826 static void ntb_qp_link_cleanup_work(struct work_struct *work)
827 {
828 struct ntb_transport_qp *qp = container_of(work,
829 struct ntb_transport_qp,
830 link_cleanup);
831 struct ntb_transport_ctx *nt = qp->transport;
832
833 ntb_qp_link_cleanup(qp);
834
835 if (nt->link_is_up)
836 schedule_delayed_work(&qp->link_work,
837 msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT));
838 }
839
840 static void ntb_qp_link_down(struct ntb_transport_qp *qp)
841 {
842 schedule_work(&qp->link_cleanup);
843 }
844
845 static void ntb_transport_link_cleanup(struct ntb_transport_ctx *nt)
846 {
847 struct ntb_transport_qp *qp;
848 u64 qp_bitmap_alloc;
849 unsigned int i, count;
850
851 qp_bitmap_alloc = nt->qp_bitmap & ~nt->qp_bitmap_free;
852
853 /* Pass along the info to any clients */
854 for (i = 0; i < nt->qp_count; i++)
855 if (qp_bitmap_alloc & BIT_ULL(i)) {
856 qp = &nt->qp_vec[i];
857 ntb_qp_link_cleanup(qp);
858 cancel_work_sync(&qp->link_cleanup);
859 cancel_delayed_work_sync(&qp->link_work);
860 }
861
862 if (!nt->link_is_up)
863 cancel_delayed_work_sync(&nt->link_work);
864
865 /* The scratchpad registers keep the values if the remote side
866 * goes down, blast them now to give them a sane value the next
867 * time they are accessed
868 */
869 count = ntb_spad_count(nt->ndev);
870 for (i = 0; i < count; i++)
871 ntb_spad_write(nt->ndev, i, 0);
872 }
873
874 static void ntb_transport_link_cleanup_work(struct work_struct *work)
875 {
876 struct ntb_transport_ctx *nt =
877 container_of(work, struct ntb_transport_ctx, link_cleanup);
878
879 ntb_transport_link_cleanup(nt);
880 }
881
882 static void ntb_transport_event_callback(void *data)
883 {
884 struct ntb_transport_ctx *nt = data;
885
886 if (ntb_link_is_up(nt->ndev, NULL, NULL) == 1)
887 schedule_delayed_work(&nt->link_work, 0);
888 else
889 schedule_work(&nt->link_cleanup);
890 }
891
892 static void ntb_transport_link_work(struct work_struct *work)
893 {
894 struct ntb_transport_ctx *nt =
895 container_of(work, struct ntb_transport_ctx, link_work.work);
896 struct ntb_dev *ndev = nt->ndev;
897 struct pci_dev *pdev = ndev->pdev;
898 resource_size_t size;
899 u32 val;
900 int rc = 0, i, spad;
901
902 /* send the local info, in the opposite order of the way we read it */
903 for (i = 0; i < nt->mw_count; i++) {
904 size = nt->mw_vec[i].phys_size;
905
906 if (max_mw_size && size > max_mw_size)
907 size = max_mw_size;
908
909 spad = MW0_SZ_HIGH + (i * 2);
910 ntb_peer_spad_write(ndev, PIDX, spad, upper_32_bits(size));
911
912 spad = MW0_SZ_LOW + (i * 2);
913 ntb_peer_spad_write(ndev, PIDX, spad, lower_32_bits(size));
914 }
915
916 ntb_peer_spad_write(ndev, PIDX, NUM_MWS, nt->mw_count);
917
918 ntb_peer_spad_write(ndev, PIDX, NUM_QPS, nt->qp_count);
919
920 ntb_peer_spad_write(ndev, PIDX, VERSION, NTB_TRANSPORT_VERSION);
921
922 /* Query the remote side for its info */
923 val = ntb_spad_read(ndev, VERSION);
924 dev_dbg(&pdev->dev, "Remote version = %d\n", val);
925 if (val != NTB_TRANSPORT_VERSION)
926 goto out;
927
928 val = ntb_spad_read(ndev, NUM_QPS);
929 dev_dbg(&pdev->dev, "Remote max number of qps = %d\n", val);
930 if (val != nt->qp_count)
931 goto out;
932
933 val = ntb_spad_read(ndev, NUM_MWS);
934 dev_dbg(&pdev->dev, "Remote number of mws = %d\n", val);
935 if (val != nt->mw_count)
936 goto out;
937
938 for (i = 0; i < nt->mw_count; i++) {
939 u64 val64;
940
941 val = ntb_spad_read(ndev, MW0_SZ_HIGH + (i * 2));
942 val64 = (u64)val << 32;
943
944 val = ntb_spad_read(ndev, MW0_SZ_LOW + (i * 2));
945 val64 |= val;
946
947 dev_dbg(&pdev->dev, "Remote MW%d size = %#llx\n", i, val64);
948
949 rc = ntb_set_mw(nt, i, val64);
950 if (rc)
951 goto out1;
952 }
953
954 nt->link_is_up = true;
955
956 for (i = 0; i < nt->qp_count; i++) {
957 struct ntb_transport_qp *qp = &nt->qp_vec[i];
958
959 ntb_transport_setup_qp_mw(nt, i);
960
961 if (qp->client_ready)
962 schedule_delayed_work(&qp->link_work, 0);
963 }
964
965 return;
966
967 out1:
968 for (i = 0; i < nt->mw_count; i++)
969 ntb_free_mw(nt, i);
970
971 /* if there's an actual failure, we should just bail */
972 if (rc < 0)
973 return;
974
975 out:
976 if (ntb_link_is_up(ndev, NULL, NULL) == 1)
977 schedule_delayed_work(&nt->link_work,
978 msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT));
979 }
980
981 static void ntb_qp_link_work(struct work_struct *work)
982 {
983 struct ntb_transport_qp *qp = container_of(work,
984 struct ntb_transport_qp,
985 link_work.work);
986 struct pci_dev *pdev = qp->ndev->pdev;
987 struct ntb_transport_ctx *nt = qp->transport;
988 int val;
989
990 WARN_ON(!nt->link_is_up);
991
992 val = ntb_spad_read(nt->ndev, QP_LINKS);
993
994 ntb_peer_spad_write(nt->ndev, PIDX, QP_LINKS, val | BIT(qp->qp_num));
995
996 /* query remote spad for qp ready bits */
997 dev_dbg_ratelimited(&pdev->dev, "Remote QP link status = %x\n", val);
998
999 /* See if the remote side is up */
1000 if (val & BIT(qp->qp_num)) {
1001 dev_info(&pdev->dev, "qp %d: Link Up\n", qp->qp_num);
1002 qp->link_is_up = true;
1003 qp->active = true;
1004
1005 if (qp->event_handler)
1006 qp->event_handler(qp->cb_data, qp->link_is_up);
1007
1008 if (qp->active)
1009 tasklet_schedule(&qp->rxc_db_work);
1010 } else if (nt->link_is_up)
1011 schedule_delayed_work(&qp->link_work,
1012 msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT));
1013 }
1014
1015 static int ntb_transport_init_queue(struct ntb_transport_ctx *nt,
1016 unsigned int qp_num)
1017 {
1018 struct ntb_transport_qp *qp;
1019 phys_addr_t mw_base;
1020 resource_size_t mw_size;
1021 unsigned int num_qps_mw, tx_size;
1022 unsigned int mw_num, mw_count, qp_count;
1023 u64 qp_offset;
1024
1025 mw_count = nt->mw_count;
1026 qp_count = nt->qp_count;
1027
1028 mw_num = QP_TO_MW(nt, qp_num);
1029
1030 qp = &nt->qp_vec[qp_num];
1031 qp->qp_num = qp_num;
1032 qp->transport = nt;
1033 qp->ndev = nt->ndev;
1034 qp->client_ready = false;
1035 qp->event_handler = NULL;
1036 ntb_qp_link_down_reset(qp);
1037
1038 if (mw_num < qp_count % mw_count)
1039 num_qps_mw = qp_count / mw_count + 1;
1040 else
1041 num_qps_mw = qp_count / mw_count;
1042
1043 mw_base = nt->mw_vec[mw_num].phys_addr;
1044 mw_size = nt->mw_vec[mw_num].phys_size;
1045
1046 if (max_mw_size && mw_size > max_mw_size)
1047 mw_size = max_mw_size;
1048
1049 tx_size = (unsigned int)mw_size / num_qps_mw;
1050 qp_offset = tx_size * (qp_num / mw_count);
1051
1052 qp->tx_mw = nt->mw_vec[mw_num].vbase + qp_offset;
1053 if (!qp->tx_mw)
1054 return -EINVAL;
1055
1056 qp->tx_mw_phys = mw_base + qp_offset;
1057 if (!qp->tx_mw_phys)
1058 return -EINVAL;
1059
1060 tx_size -= sizeof(struct ntb_rx_info);
1061 qp->rx_info = qp->tx_mw + tx_size;
1062
1063 /* Due to housekeeping, there must be atleast 2 buffs */
1064 qp->tx_max_frame = min(transport_mtu, tx_size / 2);
1065 qp->tx_max_entry = tx_size / qp->tx_max_frame;
1066
1067 if (nt->debugfs_node_dir) {
1068 char debugfs_name[4];
1069
1070 snprintf(debugfs_name, 4, "qp%d", qp_num);
1071 qp->debugfs_dir = debugfs_create_dir(debugfs_name,
1072 nt->debugfs_node_dir);
1073
1074 qp->debugfs_stats = debugfs_create_file("stats", S_IRUSR,
1075 qp->debugfs_dir, qp,
1076 &ntb_qp_debugfs_stats);
1077 } else {
1078 qp->debugfs_dir = NULL;
1079 qp->debugfs_stats = NULL;
1080 }
1081
1082 INIT_DELAYED_WORK(&qp->link_work, ntb_qp_link_work);
1083 INIT_WORK(&qp->link_cleanup, ntb_qp_link_cleanup_work);
1084
1085 spin_lock_init(&qp->ntb_rx_q_lock);
1086 spin_lock_init(&qp->ntb_tx_free_q_lock);
1087
1088 INIT_LIST_HEAD(&qp->rx_post_q);
1089 INIT_LIST_HEAD(&qp->rx_pend_q);
1090 INIT_LIST_HEAD(&qp->rx_free_q);
1091 INIT_LIST_HEAD(&qp->tx_free_q);
1092
1093 tasklet_init(&qp->rxc_db_work, ntb_transport_rxc_db,
1094 (unsigned long)qp);
1095
1096 return 0;
1097 }
1098
1099 static int ntb_transport_probe(struct ntb_client *self, struct ntb_dev *ndev)
1100 {
1101 struct ntb_transport_ctx *nt;
1102 struct ntb_transport_mw *mw;
1103 unsigned int mw_count, qp_count, spad_count, max_mw_count_for_spads;
1104 u64 qp_bitmap;
1105 int node;
1106 int rc, i;
1107
1108 mw_count = ntb_peer_mw_count(ndev);
1109
1110 if (!ndev->ops->mw_set_trans) {
1111 dev_err(&ndev->dev, "Inbound MW based NTB API is required\n");
1112 return -EINVAL;
1113 }
1114
1115 if (ntb_db_is_unsafe(ndev))
1116 dev_dbg(&ndev->dev,
1117 "doorbell is unsafe, proceed anyway...\n");
1118 if (ntb_spad_is_unsafe(ndev))
1119 dev_dbg(&ndev->dev,
1120 "scratchpad is unsafe, proceed anyway...\n");
1121
1122 if (ntb_peer_port_count(ndev) != NTB_DEF_PEER_CNT)
1123 dev_warn(&ndev->dev, "Multi-port NTB devices unsupported\n");
1124
1125 node = dev_to_node(&ndev->dev);
1126
1127 nt = kzalloc_node(sizeof(*nt), GFP_KERNEL, node);
1128 if (!nt)
1129 return -ENOMEM;
1130
1131 nt->ndev = ndev;
1132 spad_count = ntb_spad_count(ndev);
1133
1134 /* Limit the MW's based on the availability of scratchpads */
1135
1136 if (spad_count < NTB_TRANSPORT_MIN_SPADS) {
1137 nt->mw_count = 0;
1138 rc = -EINVAL;
1139 goto err;
1140 }
1141
1142 max_mw_count_for_spads = (spad_count - MW0_SZ_HIGH) / 2;
1143 nt->mw_count = min(mw_count, max_mw_count_for_spads);
1144
1145 nt->mw_vec = kcalloc_node(mw_count, sizeof(*nt->mw_vec),
1146 GFP_KERNEL, node);
1147 if (!nt->mw_vec) {
1148 rc = -ENOMEM;
1149 goto err;
1150 }
1151
1152 for (i = 0; i < mw_count; i++) {
1153 mw = &nt->mw_vec[i];
1154
1155 rc = ntb_peer_mw_get_addr(ndev, i, &mw->phys_addr,
1156 &mw->phys_size);
1157 if (rc)
1158 goto err1;
1159
1160 mw->vbase = ioremap_wc(mw->phys_addr, mw->phys_size);
1161 if (!mw->vbase) {
1162 rc = -ENOMEM;
1163 goto err1;
1164 }
1165
1166 mw->buff_size = 0;
1167 mw->xlat_size = 0;
1168 mw->virt_addr = NULL;
1169 mw->dma_addr = 0;
1170 }
1171
1172 qp_bitmap = ntb_db_valid_mask(ndev);
1173
1174 qp_count = ilog2(qp_bitmap);
1175 if (max_num_clients && max_num_clients < qp_count)
1176 qp_count = max_num_clients;
1177 else if (nt->mw_count < qp_count)
1178 qp_count = nt->mw_count;
1179
1180 qp_bitmap &= BIT_ULL(qp_count) - 1;
1181
1182 nt->qp_count = qp_count;
1183 nt->qp_bitmap = qp_bitmap;
1184 nt->qp_bitmap_free = qp_bitmap;
1185
1186 nt->qp_vec = kcalloc_node(qp_count, sizeof(*nt->qp_vec),
1187 GFP_KERNEL, node);
1188 if (!nt->qp_vec) {
1189 rc = -ENOMEM;
1190 goto err1;
1191 }
1192
1193 if (nt_debugfs_dir) {
1194 nt->debugfs_node_dir =
1195 debugfs_create_dir(pci_name(ndev->pdev),
1196 nt_debugfs_dir);
1197 }
1198
1199 for (i = 0; i < qp_count; i++) {
1200 rc = ntb_transport_init_queue(nt, i);
1201 if (rc)
1202 goto err2;
1203 }
1204
1205 INIT_DELAYED_WORK(&nt->link_work, ntb_transport_link_work);
1206 INIT_WORK(&nt->link_cleanup, ntb_transport_link_cleanup_work);
1207
1208 rc = ntb_set_ctx(ndev, nt, &ntb_transport_ops);
1209 if (rc)
1210 goto err2;
1211
1212 INIT_LIST_HEAD(&nt->client_devs);
1213 rc = ntb_bus_init(nt);
1214 if (rc)
1215 goto err3;
1216
1217 nt->link_is_up = false;
1218 ntb_link_enable(ndev, NTB_SPEED_AUTO, NTB_WIDTH_AUTO);
1219 ntb_link_event(ndev);
1220
1221 return 0;
1222
1223 err3:
1224 ntb_clear_ctx(ndev);
1225 err2:
1226 kfree(nt->qp_vec);
1227 err1:
1228 while (i--) {
1229 mw = &nt->mw_vec[i];
1230 iounmap(mw->vbase);
1231 }
1232 kfree(nt->mw_vec);
1233 err:
1234 kfree(nt);
1235 return rc;
1236 }
1237
1238 static void ntb_transport_free(struct ntb_client *self, struct ntb_dev *ndev)
1239 {
1240 struct ntb_transport_ctx *nt = ndev->ctx;
1241 struct ntb_transport_qp *qp;
1242 u64 qp_bitmap_alloc;
1243 int i;
1244
1245 ntb_transport_link_cleanup(nt);
1246 cancel_work_sync(&nt->link_cleanup);
1247 cancel_delayed_work_sync(&nt->link_work);
1248
1249 qp_bitmap_alloc = nt->qp_bitmap & ~nt->qp_bitmap_free;
1250
1251 /* verify that all the qp's are freed */
1252 for (i = 0; i < nt->qp_count; i++) {
1253 qp = &nt->qp_vec[i];
1254 if (qp_bitmap_alloc & BIT_ULL(i))
1255 ntb_transport_free_queue(qp);
1256 debugfs_remove_recursive(qp->debugfs_dir);
1257 }
1258
1259 ntb_link_disable(ndev);
1260 ntb_clear_ctx(ndev);
1261
1262 ntb_bus_remove(nt);
1263
1264 for (i = nt->mw_count; i--; ) {
1265 ntb_free_mw(nt, i);
1266 iounmap(nt->mw_vec[i].vbase);
1267 }
1268
1269 kfree(nt->qp_vec);
1270 kfree(nt->mw_vec);
1271 kfree(nt);
1272 }
1273
1274 static void ntb_complete_rxc(struct ntb_transport_qp *qp)
1275 {
1276 struct ntb_queue_entry *entry;
1277 void *cb_data;
1278 unsigned int len;
1279 unsigned long irqflags;
1280
1281 spin_lock_irqsave(&qp->ntb_rx_q_lock, irqflags);
1282
1283 while (!list_empty(&qp->rx_post_q)) {
1284 entry = list_first_entry(&qp->rx_post_q,
1285 struct ntb_queue_entry, entry);
1286 if (!(entry->flags & DESC_DONE_FLAG))
1287 break;
1288
1289 entry->rx_hdr->flags = 0;
1290 iowrite32(entry->rx_index, &qp->rx_info->entry);
1291
1292 cb_data = entry->cb_data;
1293 len = entry->len;
1294
1295 list_move_tail(&entry->entry, &qp->rx_free_q);
1296
1297 spin_unlock_irqrestore(&qp->ntb_rx_q_lock, irqflags);
1298
1299 if (qp->rx_handler && qp->client_ready)
1300 qp->rx_handler(qp, qp->cb_data, cb_data, len);
1301
1302 spin_lock_irqsave(&qp->ntb_rx_q_lock, irqflags);
1303 }
1304
1305 spin_unlock_irqrestore(&qp->ntb_rx_q_lock, irqflags);
1306 }
1307
1308 static void ntb_rx_copy_callback(void *data,
1309 const struct dmaengine_result *res)
1310 {
1311 struct ntb_queue_entry *entry = data;
1312
1313 /* we need to check DMA results if we are using DMA */
1314 if (res) {
1315 enum dmaengine_tx_result dma_err = res->result;
1316
1317 switch (dma_err) {
1318 case DMA_TRANS_READ_FAILED:
1319 case DMA_TRANS_WRITE_FAILED:
1320 entry->errors++;
1321 /* fall through */
1322 case DMA_TRANS_ABORTED:
1323 {
1324 struct ntb_transport_qp *qp = entry->qp;
1325 void *offset = qp->rx_buff + qp->rx_max_frame *
1326 qp->rx_index;
1327
1328 ntb_memcpy_rx(entry, offset);
1329 qp->rx_memcpy++;
1330 return;
1331 }
1332
1333 case DMA_TRANS_NOERROR:
1334 default:
1335 break;
1336 }
1337 }
1338
1339 entry->flags |= DESC_DONE_FLAG;
1340
1341 ntb_complete_rxc(entry->qp);
1342 }
1343
1344 static void ntb_memcpy_rx(struct ntb_queue_entry *entry, void *offset)
1345 {
1346 void *buf = entry->buf;
1347 size_t len = entry->len;
1348
1349 memcpy(buf, offset, len);
1350
1351 /* Ensure that the data is fully copied out before clearing the flag */
1352 wmb();
1353
1354 ntb_rx_copy_callback(entry, NULL);
1355 }
1356
1357 static int ntb_async_rx_submit(struct ntb_queue_entry *entry, void *offset)
1358 {
1359 struct dma_async_tx_descriptor *txd;
1360 struct ntb_transport_qp *qp = entry->qp;
1361 struct dma_chan *chan = qp->rx_dma_chan;
1362 struct dma_device *device;
1363 size_t pay_off, buff_off, len;
1364 struct dmaengine_unmap_data *unmap;
1365 dma_cookie_t cookie;
1366 void *buf = entry->buf;
1367
1368 len = entry->len;
1369 device = chan->device;
1370 pay_off = (size_t)offset & ~PAGE_MASK;
1371 buff_off = (size_t)buf & ~PAGE_MASK;
1372
1373 if (!is_dma_copy_aligned(device, pay_off, buff_off, len))
1374 goto err;
1375
1376 unmap = dmaengine_get_unmap_data(device->dev, 2, GFP_NOWAIT);
1377 if (!unmap)
1378 goto err;
1379
1380 unmap->len = len;
1381 unmap->addr[0] = dma_map_page(device->dev, virt_to_page(offset),
1382 pay_off, len, DMA_TO_DEVICE);
1383 if (dma_mapping_error(device->dev, unmap->addr[0]))
1384 goto err_get_unmap;
1385
1386 unmap->to_cnt = 1;
1387
1388 unmap->addr[1] = dma_map_page(device->dev, virt_to_page(buf),
1389 buff_off, len, DMA_FROM_DEVICE);
1390 if (dma_mapping_error(device->dev, unmap->addr[1]))
1391 goto err_get_unmap;
1392
1393 unmap->from_cnt = 1;
1394
1395 txd = device->device_prep_dma_memcpy(chan, unmap->addr[1],
1396 unmap->addr[0], len,
1397 DMA_PREP_INTERRUPT);
1398 if (!txd)
1399 goto err_get_unmap;
1400
1401 txd->callback_result = ntb_rx_copy_callback;
1402 txd->callback_param = entry;
1403 dma_set_unmap(txd, unmap);
1404
1405 cookie = dmaengine_submit(txd);
1406 if (dma_submit_error(cookie))
1407 goto err_set_unmap;
1408
1409 dmaengine_unmap_put(unmap);
1410
1411 qp->last_cookie = cookie;
1412
1413 qp->rx_async++;
1414
1415 return 0;
1416
1417 err_set_unmap:
1418 dmaengine_unmap_put(unmap);
1419 err_get_unmap:
1420 dmaengine_unmap_put(unmap);
1421 err:
1422 return -ENXIO;
1423 }
1424
1425 static void ntb_async_rx(struct ntb_queue_entry *entry, void *offset)
1426 {
1427 struct ntb_transport_qp *qp = entry->qp;
1428 struct dma_chan *chan = qp->rx_dma_chan;
1429 int res;
1430
1431 if (!chan)
1432 goto err;
1433
1434 if (entry->len < copy_bytes)
1435 goto err;
1436
1437 res = ntb_async_rx_submit(entry, offset);
1438 if (res < 0)
1439 goto err;
1440
1441 if (!entry->retries)
1442 qp->rx_async++;
1443
1444 return;
1445
1446 err:
1447 ntb_memcpy_rx(entry, offset);
1448 qp->rx_memcpy++;
1449 }
1450
1451 static int ntb_process_rxc(struct ntb_transport_qp *qp)
1452 {
1453 struct ntb_payload_header *hdr;
1454 struct ntb_queue_entry *entry;
1455 void *offset;
1456
1457 offset = qp->rx_buff + qp->rx_max_frame * qp->rx_index;
1458 hdr = offset + qp->rx_max_frame - sizeof(struct ntb_payload_header);
1459
1460 dev_dbg(&qp->ndev->pdev->dev, "qp %d: RX ver %u len %d flags %x\n",
1461 qp->qp_num, hdr->ver, hdr->len, hdr->flags);
1462
1463 if (!(hdr->flags & DESC_DONE_FLAG)) {
1464 dev_dbg(&qp->ndev->pdev->dev, "done flag not set\n");
1465 qp->rx_ring_empty++;
1466 return -EAGAIN;
1467 }
1468
1469 if (hdr->flags & LINK_DOWN_FLAG) {
1470 dev_dbg(&qp->ndev->pdev->dev, "link down flag set\n");
1471 ntb_qp_link_down(qp);
1472 hdr->flags = 0;
1473 return -EAGAIN;
1474 }
1475
1476 if (hdr->ver != (u32)qp->rx_pkts) {
1477 dev_dbg(&qp->ndev->pdev->dev,
1478 "version mismatch, expected %llu - got %u\n",
1479 qp->rx_pkts, hdr->ver);
1480 qp->rx_err_ver++;
1481 return -EIO;
1482 }
1483
1484 entry = ntb_list_mv(&qp->ntb_rx_q_lock, &qp->rx_pend_q, &qp->rx_post_q);
1485 if (!entry) {
1486 dev_dbg(&qp->ndev->pdev->dev, "no receive buffer\n");
1487 qp->rx_err_no_buf++;
1488 return -EAGAIN;
1489 }
1490
1491 entry->rx_hdr = hdr;
1492 entry->rx_index = qp->rx_index;
1493
1494 if (hdr->len > entry->len) {
1495 dev_dbg(&qp->ndev->pdev->dev,
1496 "receive buffer overflow! Wanted %d got %d\n",
1497 hdr->len, entry->len);
1498 qp->rx_err_oflow++;
1499
1500 entry->len = -EIO;
1501 entry->flags |= DESC_DONE_FLAG;
1502
1503 ntb_complete_rxc(qp);
1504 } else {
1505 dev_dbg(&qp->ndev->pdev->dev,
1506 "RX OK index %u ver %u size %d into buf size %d\n",
1507 qp->rx_index, hdr->ver, hdr->len, entry->len);
1508
1509 qp->rx_bytes += hdr->len;
1510 qp->rx_pkts++;
1511
1512 entry->len = hdr->len;
1513
1514 ntb_async_rx(entry, offset);
1515 }
1516
1517 qp->rx_index++;
1518 qp->rx_index %= qp->rx_max_entry;
1519
1520 return 0;
1521 }
1522
1523 static void ntb_transport_rxc_db(unsigned long data)
1524 {
1525 struct ntb_transport_qp *qp = (void *)data;
1526 int rc, i;
1527
1528 dev_dbg(&qp->ndev->pdev->dev, "%s: doorbell %d received\n",
1529 __func__, qp->qp_num);
1530
1531 /* Limit the number of packets processed in a single interrupt to
1532 * provide fairness to others
1533 */
1534 for (i = 0; i < qp->rx_max_entry; i++) {
1535 rc = ntb_process_rxc(qp);
1536 if (rc)
1537 break;
1538 }
1539
1540 if (i && qp->rx_dma_chan)
1541 dma_async_issue_pending(qp->rx_dma_chan);
1542
1543 if (i == qp->rx_max_entry) {
1544 /* there is more work to do */
1545 if (qp->active)
1546 tasklet_schedule(&qp->rxc_db_work);
1547 } else if (ntb_db_read(qp->ndev) & BIT_ULL(qp->qp_num)) {
1548 /* the doorbell bit is set: clear it */
1549 ntb_db_clear(qp->ndev, BIT_ULL(qp->qp_num));
1550 /* ntb_db_read ensures ntb_db_clear write is committed */
1551 ntb_db_read(qp->ndev);
1552
1553 /* an interrupt may have arrived between finishing
1554 * ntb_process_rxc and clearing the doorbell bit:
1555 * there might be some more work to do.
1556 */
1557 if (qp->active)
1558 tasklet_schedule(&qp->rxc_db_work);
1559 }
1560 }
1561
1562 static void ntb_tx_copy_callback(void *data,
1563 const struct dmaengine_result *res)
1564 {
1565 struct ntb_queue_entry *entry = data;
1566 struct ntb_transport_qp *qp = entry->qp;
1567 struct ntb_payload_header __iomem *hdr = entry->tx_hdr;
1568
1569 /* we need to check DMA results if we are using DMA */
1570 if (res) {
1571 enum dmaengine_tx_result dma_err = res->result;
1572
1573 switch (dma_err) {
1574 case DMA_TRANS_READ_FAILED:
1575 case DMA_TRANS_WRITE_FAILED:
1576 entry->errors++;
1577 /* fall through */
1578 case DMA_TRANS_ABORTED:
1579 {
1580 void __iomem *offset =
1581 qp->tx_mw + qp->tx_max_frame *
1582 entry->tx_index;
1583
1584 /* resubmit via CPU */
1585 ntb_memcpy_tx(entry, offset);
1586 qp->tx_memcpy++;
1587 return;
1588 }
1589
1590 case DMA_TRANS_NOERROR:
1591 default:
1592 break;
1593 }
1594 }
1595
1596 iowrite32(entry->flags | DESC_DONE_FLAG, &hdr->flags);
1597
1598 ntb_peer_db_set(qp->ndev, BIT_ULL(qp->qp_num));
1599
1600 /* The entry length can only be zero if the packet is intended to be a
1601 * "link down" or similar. Since no payload is being sent in these
1602 * cases, there is nothing to add to the completion queue.
1603 */
1604 if (entry->len > 0) {
1605 qp->tx_bytes += entry->len;
1606
1607 if (qp->tx_handler)
1608 qp->tx_handler(qp, qp->cb_data, entry->cb_data,
1609 entry->len);
1610 }
1611
1612 ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, &qp->tx_free_q);
1613 }
1614
1615 static void ntb_memcpy_tx(struct ntb_queue_entry *entry, void __iomem *offset)
1616 {
1617 #ifdef ARCH_HAS_NOCACHE_UACCESS
1618 /*
1619 * Using non-temporal mov to improve performance on non-cached
1620 * writes, even though we aren't actually copying from user space.
1621 */
1622 __copy_from_user_inatomic_nocache(offset, entry->buf, entry->len);
1623 #else
1624 memcpy_toio(offset, entry->buf, entry->len);
1625 #endif
1626
1627 /* Ensure that the data is fully copied out before setting the flags */
1628 wmb();
1629
1630 ntb_tx_copy_callback(entry, NULL);
1631 }
1632
1633 static int ntb_async_tx_submit(struct ntb_transport_qp *qp,
1634 struct ntb_queue_entry *entry)
1635 {
1636 struct dma_async_tx_descriptor *txd;
1637 struct dma_chan *chan = qp->tx_dma_chan;
1638 struct dma_device *device;
1639 size_t len = entry->len;
1640 void *buf = entry->buf;
1641 size_t dest_off, buff_off;
1642 struct dmaengine_unmap_data *unmap;
1643 dma_addr_t dest;
1644 dma_cookie_t cookie;
1645
1646 device = chan->device;
1647 dest = qp->tx_mw_phys + qp->tx_max_frame * entry->tx_index;
1648 buff_off = (size_t)buf & ~PAGE_MASK;
1649 dest_off = (size_t)dest & ~PAGE_MASK;
1650
1651 if (!is_dma_copy_aligned(device, buff_off, dest_off, len))
1652 goto err;
1653
1654 unmap = dmaengine_get_unmap_data(device->dev, 1, GFP_NOWAIT);
1655 if (!unmap)
1656 goto err;
1657
1658 unmap->len = len;
1659 unmap->addr[0] = dma_map_page(device->dev, virt_to_page(buf),
1660 buff_off, len, DMA_TO_DEVICE);
1661 if (dma_mapping_error(device->dev, unmap->addr[0]))
1662 goto err_get_unmap;
1663
1664 unmap->to_cnt = 1;
1665
1666 txd = device->device_prep_dma_memcpy(chan, dest, unmap->addr[0], len,
1667 DMA_PREP_INTERRUPT);
1668 if (!txd)
1669 goto err_get_unmap;
1670
1671 txd->callback_result = ntb_tx_copy_callback;
1672 txd->callback_param = entry;
1673 dma_set_unmap(txd, unmap);
1674
1675 cookie = dmaengine_submit(txd);
1676 if (dma_submit_error(cookie))
1677 goto err_set_unmap;
1678
1679 dmaengine_unmap_put(unmap);
1680
1681 dma_async_issue_pending(chan);
1682
1683 return 0;
1684 err_set_unmap:
1685 dmaengine_unmap_put(unmap);
1686 err_get_unmap:
1687 dmaengine_unmap_put(unmap);
1688 err:
1689 return -ENXIO;
1690 }
1691
1692 static void ntb_async_tx(struct ntb_transport_qp *qp,
1693 struct ntb_queue_entry *entry)
1694 {
1695 struct ntb_payload_header __iomem *hdr;
1696 struct dma_chan *chan = qp->tx_dma_chan;
1697 void __iomem *offset;
1698 int res;
1699
1700 entry->tx_index = qp->tx_index;
1701 offset = qp->tx_mw + qp->tx_max_frame * entry->tx_index;
1702 hdr = offset + qp->tx_max_frame - sizeof(struct ntb_payload_header);
1703 entry->tx_hdr = hdr;
1704
1705 iowrite32(entry->len, &hdr->len);
1706 iowrite32((u32)qp->tx_pkts, &hdr->ver);
1707
1708 if (!chan)
1709 goto err;
1710
1711 if (entry->len < copy_bytes)
1712 goto err;
1713
1714 res = ntb_async_tx_submit(qp, entry);
1715 if (res < 0)
1716 goto err;
1717
1718 if (!entry->retries)
1719 qp->tx_async++;
1720
1721 return;
1722
1723 err:
1724 ntb_memcpy_tx(entry, offset);
1725 qp->tx_memcpy++;
1726 }
1727
1728 static int ntb_process_tx(struct ntb_transport_qp *qp,
1729 struct ntb_queue_entry *entry)
1730 {
1731 if (qp->tx_index == qp->remote_rx_info->entry) {
1732 qp->tx_ring_full++;
1733 return -EAGAIN;
1734 }
1735
1736 if (entry->len > qp->tx_max_frame - sizeof(struct ntb_payload_header)) {
1737 if (qp->tx_handler)
1738 qp->tx_handler(qp, qp->cb_data, NULL, -EIO);
1739
1740 ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry,
1741 &qp->tx_free_q);
1742 return 0;
1743 }
1744
1745 ntb_async_tx(qp, entry);
1746
1747 qp->tx_index++;
1748 qp->tx_index %= qp->tx_max_entry;
1749
1750 qp->tx_pkts++;
1751
1752 return 0;
1753 }
1754
1755 static void ntb_send_link_down(struct ntb_transport_qp *qp)
1756 {
1757 struct pci_dev *pdev = qp->ndev->pdev;
1758 struct ntb_queue_entry *entry;
1759 int i, rc;
1760
1761 if (!qp->link_is_up)
1762 return;
1763
1764 dev_info(&pdev->dev, "qp %d: Send Link Down\n", qp->qp_num);
1765
1766 for (i = 0; i < NTB_LINK_DOWN_TIMEOUT; i++) {
1767 entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q);
1768 if (entry)
1769 break;
1770 msleep(100);
1771 }
1772
1773 if (!entry)
1774 return;
1775
1776 entry->cb_data = NULL;
1777 entry->buf = NULL;
1778 entry->len = 0;
1779 entry->flags = LINK_DOWN_FLAG;
1780
1781 rc = ntb_process_tx(qp, entry);
1782 if (rc)
1783 dev_err(&pdev->dev, "ntb: QP%d unable to send linkdown msg\n",
1784 qp->qp_num);
1785
1786 ntb_qp_link_down_reset(qp);
1787 }
1788
1789 static bool ntb_dma_filter_fn(struct dma_chan *chan, void *node)
1790 {
1791 return dev_to_node(&chan->dev->device) == (int)(unsigned long)node;
1792 }
1793
1794 /**
1795 * ntb_transport_create_queue - Create a new NTB transport layer queue
1796 * @rx_handler: receive callback function
1797 * @tx_handler: transmit callback function
1798 * @event_handler: event callback function
1799 *
1800 * Create a new NTB transport layer queue and provide the queue with a callback
1801 * routine for both transmit and receive. The receive callback routine will be
1802 * used to pass up data when the transport has received it on the queue. The
1803 * transmit callback routine will be called when the transport has completed the
1804 * transmission of the data on the queue and the data is ready to be freed.
1805 *
1806 * RETURNS: pointer to newly created ntb_queue, NULL on error.
1807 */
1808 struct ntb_transport_qp *
1809 ntb_transport_create_queue(void *data, struct device *client_dev,
1810 const struct ntb_queue_handlers *handlers)
1811 {
1812 struct ntb_dev *ndev;
1813 struct pci_dev *pdev;
1814 struct ntb_transport_ctx *nt;
1815 struct ntb_queue_entry *entry;
1816 struct ntb_transport_qp *qp;
1817 u64 qp_bit;
1818 unsigned int free_queue;
1819 dma_cap_mask_t dma_mask;
1820 int node;
1821 int i;
1822
1823 ndev = dev_ntb(client_dev->parent);
1824 pdev = ndev->pdev;
1825 nt = ndev->ctx;
1826
1827 node = dev_to_node(&ndev->dev);
1828
1829 free_queue = ffs(nt->qp_bitmap_free);
1830 if (!free_queue)
1831 goto err;
1832
1833 /* decrement free_queue to make it zero based */
1834 free_queue--;
1835
1836 qp = &nt->qp_vec[free_queue];
1837 qp_bit = BIT_ULL(qp->qp_num);
1838
1839 nt->qp_bitmap_free &= ~qp_bit;
1840
1841 qp->cb_data = data;
1842 qp->rx_handler = handlers->rx_handler;
1843 qp->tx_handler = handlers->tx_handler;
1844 qp->event_handler = handlers->event_handler;
1845
1846 dma_cap_zero(dma_mask);
1847 dma_cap_set(DMA_MEMCPY, dma_mask);
1848
1849 if (use_dma) {
1850 qp->tx_dma_chan =
1851 dma_request_channel(dma_mask, ntb_dma_filter_fn,
1852 (void *)(unsigned long)node);
1853 if (!qp->tx_dma_chan)
1854 dev_info(&pdev->dev, "Unable to allocate TX DMA channel\n");
1855
1856 qp->rx_dma_chan =
1857 dma_request_channel(dma_mask, ntb_dma_filter_fn,
1858 (void *)(unsigned long)node);
1859 if (!qp->rx_dma_chan)
1860 dev_info(&pdev->dev, "Unable to allocate RX DMA channel\n");
1861 } else {
1862 qp->tx_dma_chan = NULL;
1863 qp->rx_dma_chan = NULL;
1864 }
1865
1866 dev_dbg(&pdev->dev, "Using %s memcpy for TX\n",
1867 qp->tx_dma_chan ? "DMA" : "CPU");
1868
1869 dev_dbg(&pdev->dev, "Using %s memcpy for RX\n",
1870 qp->rx_dma_chan ? "DMA" : "CPU");
1871
1872 for (i = 0; i < NTB_QP_DEF_NUM_ENTRIES; i++) {
1873 entry = kzalloc_node(sizeof(*entry), GFP_KERNEL, node);
1874 if (!entry)
1875 goto err1;
1876
1877 entry->qp = qp;
1878 ntb_list_add(&qp->ntb_rx_q_lock, &entry->entry,
1879 &qp->rx_free_q);
1880 }
1881 qp->rx_alloc_entry = NTB_QP_DEF_NUM_ENTRIES;
1882
1883 for (i = 0; i < qp->tx_max_entry; i++) {
1884 entry = kzalloc_node(sizeof(*entry), GFP_KERNEL, node);
1885 if (!entry)
1886 goto err2;
1887
1888 entry->qp = qp;
1889 ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry,
1890 &qp->tx_free_q);
1891 }
1892
1893 ntb_db_clear(qp->ndev, qp_bit);
1894 ntb_db_clear_mask(qp->ndev, qp_bit);
1895
1896 dev_info(&pdev->dev, "NTB Transport QP %d created\n", qp->qp_num);
1897
1898 return qp;
1899
1900 err2:
1901 while ((entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q)))
1902 kfree(entry);
1903 err1:
1904 qp->rx_alloc_entry = 0;
1905 while ((entry = ntb_list_rm(&qp->ntb_rx_q_lock, &qp->rx_free_q)))
1906 kfree(entry);
1907 if (qp->tx_dma_chan)
1908 dma_release_channel(qp->tx_dma_chan);
1909 if (qp->rx_dma_chan)
1910 dma_release_channel(qp->rx_dma_chan);
1911 nt->qp_bitmap_free |= qp_bit;
1912 err:
1913 return NULL;
1914 }
1915 EXPORT_SYMBOL_GPL(ntb_transport_create_queue);
1916
1917 /**
1918 * ntb_transport_free_queue - Frees NTB transport queue
1919 * @qp: NTB queue to be freed
1920 *
1921 * Frees NTB transport queue
1922 */
1923 void ntb_transport_free_queue(struct ntb_transport_qp *qp)
1924 {
1925 struct pci_dev *pdev;
1926 struct ntb_queue_entry *entry;
1927 u64 qp_bit;
1928
1929 if (!qp)
1930 return;
1931
1932 pdev = qp->ndev->pdev;
1933
1934 qp->active = false;
1935
1936 if (qp->tx_dma_chan) {
1937 struct dma_chan *chan = qp->tx_dma_chan;
1938 /* Putting the dma_chan to NULL will force any new traffic to be
1939 * processed by the CPU instead of the DAM engine
1940 */
1941 qp->tx_dma_chan = NULL;
1942
1943 /* Try to be nice and wait for any queued DMA engine
1944 * transactions to process before smashing it with a rock
1945 */
1946 dma_sync_wait(chan, qp->last_cookie);
1947 dmaengine_terminate_all(chan);
1948 dma_release_channel(chan);
1949 }
1950
1951 if (qp->rx_dma_chan) {
1952 struct dma_chan *chan = qp->rx_dma_chan;
1953 /* Putting the dma_chan to NULL will force any new traffic to be
1954 * processed by the CPU instead of the DAM engine
1955 */
1956 qp->rx_dma_chan = NULL;
1957
1958 /* Try to be nice and wait for any queued DMA engine
1959 * transactions to process before smashing it with a rock
1960 */
1961 dma_sync_wait(chan, qp->last_cookie);
1962 dmaengine_terminate_all(chan);
1963 dma_release_channel(chan);
1964 }
1965
1966 qp_bit = BIT_ULL(qp->qp_num);
1967
1968 ntb_db_set_mask(qp->ndev, qp_bit);
1969 tasklet_kill(&qp->rxc_db_work);
1970
1971 cancel_delayed_work_sync(&qp->link_work);
1972
1973 qp->cb_data = NULL;
1974 qp->rx_handler = NULL;
1975 qp->tx_handler = NULL;
1976 qp->event_handler = NULL;
1977
1978 while ((entry = ntb_list_rm(&qp->ntb_rx_q_lock, &qp->rx_free_q)))
1979 kfree(entry);
1980
1981 while ((entry = ntb_list_rm(&qp->ntb_rx_q_lock, &qp->rx_pend_q))) {
1982 dev_warn(&pdev->dev, "Freeing item from non-empty rx_pend_q\n");
1983 kfree(entry);
1984 }
1985
1986 while ((entry = ntb_list_rm(&qp->ntb_rx_q_lock, &qp->rx_post_q))) {
1987 dev_warn(&pdev->dev, "Freeing item from non-empty rx_post_q\n");
1988 kfree(entry);
1989 }
1990
1991 while ((entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q)))
1992 kfree(entry);
1993
1994 qp->transport->qp_bitmap_free |= qp_bit;
1995
1996 dev_info(&pdev->dev, "NTB Transport QP %d freed\n", qp->qp_num);
1997 }
1998 EXPORT_SYMBOL_GPL(ntb_transport_free_queue);
1999
2000 /**
2001 * ntb_transport_rx_remove - Dequeues enqueued rx packet
2002 * @qp: NTB queue to be freed
2003 * @len: pointer to variable to write enqueued buffers length
2004 *
2005 * Dequeues unused buffers from receive queue. Should only be used during
2006 * shutdown of qp.
2007 *
2008 * RETURNS: NULL error value on error, or void* for success.
2009 */
2010 void *ntb_transport_rx_remove(struct ntb_transport_qp *qp, unsigned int *len)
2011 {
2012 struct ntb_queue_entry *entry;
2013 void *buf;
2014
2015 if (!qp || qp->client_ready)
2016 return NULL;
2017
2018 entry = ntb_list_rm(&qp->ntb_rx_q_lock, &qp->rx_pend_q);
2019 if (!entry)
2020 return NULL;
2021
2022 buf = entry->cb_data;
2023 *len = entry->len;
2024
2025 ntb_list_add(&qp->ntb_rx_q_lock, &entry->entry, &qp->rx_free_q);
2026
2027 return buf;
2028 }
2029 EXPORT_SYMBOL_GPL(ntb_transport_rx_remove);
2030
2031 /**
2032 * ntb_transport_rx_enqueue - Enqueue a new NTB queue entry
2033 * @qp: NTB transport layer queue the entry is to be enqueued on
2034 * @cb: per buffer pointer for callback function to use
2035 * @data: pointer to data buffer that incoming packets will be copied into
2036 * @len: length of the data buffer
2037 *
2038 * Enqueue a new receive buffer onto the transport queue into which a NTB
2039 * payload can be received into.
2040 *
2041 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
2042 */
2043 int ntb_transport_rx_enqueue(struct ntb_transport_qp *qp, void *cb, void *data,
2044 unsigned int len)
2045 {
2046 struct ntb_queue_entry *entry;
2047
2048 if (!qp)
2049 return -EINVAL;
2050
2051 entry = ntb_list_rm(&qp->ntb_rx_q_lock, &qp->rx_free_q);
2052 if (!entry)
2053 return -ENOMEM;
2054
2055 entry->cb_data = cb;
2056 entry->buf = data;
2057 entry->len = len;
2058 entry->flags = 0;
2059 entry->retries = 0;
2060 entry->errors = 0;
2061 entry->rx_index = 0;
2062
2063 ntb_list_add(&qp->ntb_rx_q_lock, &entry->entry, &qp->rx_pend_q);
2064
2065 if (qp->active)
2066 tasklet_schedule(&qp->rxc_db_work);
2067
2068 return 0;
2069 }
2070 EXPORT_SYMBOL_GPL(ntb_transport_rx_enqueue);
2071
2072 /**
2073 * ntb_transport_tx_enqueue - Enqueue a new NTB queue entry
2074 * @qp: NTB transport layer queue the entry is to be enqueued on
2075 * @cb: per buffer pointer for callback function to use
2076 * @data: pointer to data buffer that will be sent
2077 * @len: length of the data buffer
2078 *
2079 * Enqueue a new transmit buffer onto the transport queue from which a NTB
2080 * payload will be transmitted. This assumes that a lock is being held to
2081 * serialize access to the qp.
2082 *
2083 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
2084 */
2085 int ntb_transport_tx_enqueue(struct ntb_transport_qp *qp, void *cb, void *data,
2086 unsigned int len)
2087 {
2088 struct ntb_queue_entry *entry;
2089 int rc;
2090
2091 if (!qp || !qp->link_is_up || !len)
2092 return -EINVAL;
2093
2094 entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q);
2095 if (!entry) {
2096 qp->tx_err_no_buf++;
2097 return -EBUSY;
2098 }
2099
2100 entry->cb_data = cb;
2101 entry->buf = data;
2102 entry->len = len;
2103 entry->flags = 0;
2104 entry->errors = 0;
2105 entry->retries = 0;
2106 entry->tx_index = 0;
2107
2108 rc = ntb_process_tx(qp, entry);
2109 if (rc)
2110 ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry,
2111 &qp->tx_free_q);
2112
2113 return rc;
2114 }
2115 EXPORT_SYMBOL_GPL(ntb_transport_tx_enqueue);
2116
2117 /**
2118 * ntb_transport_link_up - Notify NTB transport of client readiness to use queue
2119 * @qp: NTB transport layer queue to be enabled
2120 *
2121 * Notify NTB transport layer of client readiness to use queue
2122 */
2123 void ntb_transport_link_up(struct ntb_transport_qp *qp)
2124 {
2125 if (!qp)
2126 return;
2127
2128 qp->client_ready = true;
2129
2130 if (qp->transport->link_is_up)
2131 schedule_delayed_work(&qp->link_work, 0);
2132 }
2133 EXPORT_SYMBOL_GPL(ntb_transport_link_up);
2134
2135 /**
2136 * ntb_transport_link_down - Notify NTB transport to no longer enqueue data
2137 * @qp: NTB transport layer queue to be disabled
2138 *
2139 * Notify NTB transport layer of client's desire to no longer receive data on
2140 * transport queue specified. It is the client's responsibility to ensure all
2141 * entries on queue are purged or otherwise handled appropriately.
2142 */
2143 void ntb_transport_link_down(struct ntb_transport_qp *qp)
2144 {
2145 int val;
2146
2147 if (!qp)
2148 return;
2149
2150 qp->client_ready = false;
2151
2152 val = ntb_spad_read(qp->ndev, QP_LINKS);
2153
2154 ntb_peer_spad_write(qp->ndev, PIDX, QP_LINKS, val & ~BIT(qp->qp_num));
2155
2156 if (qp->link_is_up)
2157 ntb_send_link_down(qp);
2158 else
2159 cancel_delayed_work_sync(&qp->link_work);
2160 }
2161 EXPORT_SYMBOL_GPL(ntb_transport_link_down);
2162
2163 /**
2164 * ntb_transport_link_query - Query transport link state
2165 * @qp: NTB transport layer queue to be queried
2166 *
2167 * Query connectivity to the remote system of the NTB transport queue
2168 *
2169 * RETURNS: true for link up or false for link down
2170 */
2171 bool ntb_transport_link_query(struct ntb_transport_qp *qp)
2172 {
2173 if (!qp)
2174 return false;
2175
2176 return qp->link_is_up;
2177 }
2178 EXPORT_SYMBOL_GPL(ntb_transport_link_query);
2179
2180 /**
2181 * ntb_transport_qp_num - Query the qp number
2182 * @qp: NTB transport layer queue to be queried
2183 *
2184 * Query qp number of the NTB transport queue
2185 *
2186 * RETURNS: a zero based number specifying the qp number
2187 */
2188 unsigned char ntb_transport_qp_num(struct ntb_transport_qp *qp)
2189 {
2190 if (!qp)
2191 return 0;
2192
2193 return qp->qp_num;
2194 }
2195 EXPORT_SYMBOL_GPL(ntb_transport_qp_num);
2196
2197 /**
2198 * ntb_transport_max_size - Query the max payload size of a qp
2199 * @qp: NTB transport layer queue to be queried
2200 *
2201 * Query the maximum payload size permissible on the given qp
2202 *
2203 * RETURNS: the max payload size of a qp
2204 */
2205 unsigned int ntb_transport_max_size(struct ntb_transport_qp *qp)
2206 {
2207 unsigned int max_size;
2208 unsigned int copy_align;
2209 struct dma_chan *rx_chan, *tx_chan;
2210
2211 if (!qp)
2212 return 0;
2213
2214 rx_chan = qp->rx_dma_chan;
2215 tx_chan = qp->tx_dma_chan;
2216
2217 copy_align = max(rx_chan ? rx_chan->device->copy_align : 0,
2218 tx_chan ? tx_chan->device->copy_align : 0);
2219
2220 /* If DMA engine usage is possible, try to find the max size for that */
2221 max_size = qp->tx_max_frame - sizeof(struct ntb_payload_header);
2222 max_size = round_down(max_size, 1 << copy_align);
2223
2224 return max_size;
2225 }
2226 EXPORT_SYMBOL_GPL(ntb_transport_max_size);
2227
2228 unsigned int ntb_transport_tx_free_entry(struct ntb_transport_qp *qp)
2229 {
2230 unsigned int head = qp->tx_index;
2231 unsigned int tail = qp->remote_rx_info->entry;
2232
2233 return tail > head ? tail - head : qp->tx_max_entry + tail - head;
2234 }
2235 EXPORT_SYMBOL_GPL(ntb_transport_tx_free_entry);
2236
2237 static void ntb_transport_doorbell_callback(void *data, int vector)
2238 {
2239 struct ntb_transport_ctx *nt = data;
2240 struct ntb_transport_qp *qp;
2241 u64 db_bits;
2242 unsigned int qp_num;
2243
2244 db_bits = (nt->qp_bitmap & ~nt->qp_bitmap_free &
2245 ntb_db_vector_mask(nt->ndev, vector));
2246
2247 while (db_bits) {
2248 qp_num = __ffs(db_bits);
2249 qp = &nt->qp_vec[qp_num];
2250
2251 if (qp->active)
2252 tasklet_schedule(&qp->rxc_db_work);
2253
2254 db_bits &= ~BIT_ULL(qp_num);
2255 }
2256 }
2257
2258 static const struct ntb_ctx_ops ntb_transport_ops = {
2259 .link_event = ntb_transport_event_callback,
2260 .db_event = ntb_transport_doorbell_callback,
2261 };
2262
2263 static struct ntb_client ntb_transport_client = {
2264 .ops = {
2265 .probe = ntb_transport_probe,
2266 .remove = ntb_transport_free,
2267 },
2268 };
2269
2270 static int __init ntb_transport_init(void)
2271 {
2272 int rc;
2273
2274 pr_info("%s, version %s\n", NTB_TRANSPORT_DESC, NTB_TRANSPORT_VER);
2275
2276 if (debugfs_initialized())
2277 nt_debugfs_dir = debugfs_create_dir(KBUILD_MODNAME, NULL);
2278
2279 rc = bus_register(&ntb_transport_bus);
2280 if (rc)
2281 goto err_bus;
2282
2283 rc = ntb_register_client(&ntb_transport_client);
2284 if (rc)
2285 goto err_client;
2286
2287 return 0;
2288
2289 err_client:
2290 bus_unregister(&ntb_transport_bus);
2291 err_bus:
2292 debugfs_remove_recursive(nt_debugfs_dir);
2293 return rc;
2294 }
2295 module_init(ntb_transport_init);
2296
2297 static void __exit ntb_transport_exit(void)
2298 {
2299 ntb_unregister_client(&ntb_transport_client);
2300 bus_unregister(&ntb_transport_bus);
2301 debugfs_remove_recursive(nt_debugfs_dir);
2302 }
2303 module_exit(ntb_transport_exit);
Linux with added FPC-III support