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