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 70MODULE_DESCRIPTION(NTB_TRANSPORT_DESC); 71MODULE_VERSION(NTB_TRANSPORT_VER); 72MODULE_LICENSE("Dual BSD/GPL"); 73MODULE_AUTHOR("Intel Corporation"); 74 75static unsigned long max_mw_size; 76module_param(max_mw_size, ulong, 0644); 77MODULE_PARM_DESC(max_mw_size, "Limit size of large memory windows"); 78 79static unsigned int transport_mtu = 0x10000; 80module_param(transport_mtu, uint, 0644); 81MODULE_PARM_DESC(transport_mtu, "Maximum size of NTB transport packets"); 82 83static unsigned char max_num_clients; 84module_param(max_num_clients, byte, 0644); 85MODULE_PARM_DESC(max_num_clients, "Maximum number of NTB transport clients"); 86 87static unsigned int copy_bytes = 1024; 88module_param(copy_bytes, uint, 0644); 89MODULE_PARM_DESC(copy_bytes, "Threshold under which NTB will use the CPU to copy instead of DMA"); 90 91static bool use_dma; 92module_param(use_dma, bool, 0644); 93MODULE_PARM_DESC(use_dma, "Use DMA engine to perform large data copy"); 94 95static struct dentry *nt_debugfs_dir; 96 97struct ntb_queue_entry { 98 /* ntb_queue list reference */ 99 struct list_head entry; 100 /* pointers to data to be transferred */ 101 void *cb_data; 102 void *buf; 103 unsigned int len; 104 unsigned int flags; 105 106 struct ntb_transport_qp *qp; 107 union { 108 struct ntb_payload_header __iomem *tx_hdr; 109 struct ntb_payload_header *rx_hdr; 110 }; 111 unsigned int index; 112}; 113 114struct ntb_rx_info { 115 unsigned int entry; 116}; 117 118struct ntb_transport_qp { 119 struct ntb_transport_ctx *transport; 120 struct ntb_dev *ndev; 121 void *cb_data; 122 struct dma_chan *tx_dma_chan; 123 struct dma_chan *rx_dma_chan; 124 125 bool client_ready; 126 bool link_is_up; 127 128 u8 qp_num; /* Only 64 QP's are allowed. 0-63 */ 129 u64 qp_bit; 130 131 struct ntb_rx_info __iomem *rx_info; 132 struct ntb_rx_info *remote_rx_info; 133 134 void (*tx_handler)(struct ntb_transport_qp *qp, void *qp_data, 135 void *data, int len); 136 struct list_head tx_free_q; 137 spinlock_t ntb_tx_free_q_lock; 138 void __iomem *tx_mw; 139 dma_addr_t tx_mw_phys; 140 unsigned int tx_index; 141 unsigned int tx_max_entry; 142 unsigned int tx_max_frame; 143 144 void (*rx_handler)(struct ntb_transport_qp *qp, void *qp_data, 145 void *data, int len); 146 struct list_head rx_post_q; 147 struct list_head rx_pend_q; 148 struct list_head rx_free_q; 149 /* ntb_rx_q_lock: synchronize access to rx_XXXX_q */ 150 spinlock_t ntb_rx_q_lock; 151 void *rx_buff; 152 unsigned int rx_index; 153 unsigned int rx_max_entry; 154 unsigned int rx_max_frame; 155 dma_cookie_t last_cookie; 156 struct tasklet_struct rxc_db_work; 157 158 void (*event_handler)(void *data, int status); 159 struct delayed_work link_work; 160 struct work_struct link_cleanup; 161 162 struct dentry *debugfs_dir; 163 struct dentry *debugfs_stats; 164 165 /* Stats */ 166 u64 rx_bytes; 167 u64 rx_pkts; 168 u64 rx_ring_empty; 169 u64 rx_err_no_buf; 170 u64 rx_err_oflow; 171 u64 rx_err_ver; 172 u64 rx_memcpy; 173 u64 rx_async; 174 u64 tx_bytes; 175 u64 tx_pkts; 176 u64 tx_ring_full; 177 u64 tx_err_no_buf; 178 u64 tx_memcpy; 179 u64 tx_async; 180}; 181 182struct ntb_transport_mw { 183 phys_addr_t phys_addr; 184 resource_size_t phys_size; 185 resource_size_t xlat_align; 186 resource_size_t xlat_align_size; 187 void __iomem *vbase; 188 size_t xlat_size; 189 size_t buff_size; 190 void *virt_addr; 191 dma_addr_t dma_addr; 192}; 193 194struct ntb_transport_client_dev { 195 struct list_head entry; 196 struct ntb_transport_ctx *nt; 197 struct device dev; 198}; 199 200struct ntb_transport_ctx { 201 struct list_head entry; 202 struct list_head client_devs; 203 204 struct ntb_dev *ndev; 205 206 struct ntb_transport_mw *mw_vec; 207 struct ntb_transport_qp *qp_vec; 208 unsigned int mw_count; 209 unsigned int qp_count; 210 u64 qp_bitmap; 211 u64 qp_bitmap_free; 212 213 bool link_is_up; 214 struct delayed_work link_work; 215 struct work_struct link_cleanup; 216 217 struct dentry *debugfs_node_dir; 218}; 219 220enum { 221 DESC_DONE_FLAG = BIT(0), 222 LINK_DOWN_FLAG = BIT(1), 223}; 224 225struct ntb_payload_header { 226 unsigned int ver; 227 unsigned int len; 228 unsigned int flags; 229}; 230 231enum { 232 VERSION = 0, 233 QP_LINKS, 234 NUM_QPS, 235 NUM_MWS, 236 MW0_SZ_HIGH, 237 MW0_SZ_LOW, 238 MW1_SZ_HIGH, 239 MW1_SZ_LOW, 240 MAX_SPAD, 241}; 242 243#define dev_client_dev(__dev) \ 244 container_of((__dev), struct ntb_transport_client_dev, dev) 245 246#define drv_client(__drv) \ 247 container_of((__drv), struct ntb_transport_client, driver) 248 249#define QP_TO_MW(nt, qp) ((qp) % nt->mw_count) 250#define NTB_QP_DEF_NUM_ENTRIES 100 251#define NTB_LINK_DOWN_TIMEOUT 10 252 253static void ntb_transport_rxc_db(unsigned long data); 254static const struct ntb_ctx_ops ntb_transport_ops; 255static struct ntb_client ntb_transport_client; 256 257static int ntb_transport_bus_match(struct device *dev, 258 struct device_driver *drv) 259{ 260 return !strncmp(dev_name(dev), drv->name, strlen(drv->name)); 261} 262 263static int ntb_transport_bus_probe(struct device *dev) 264{ 265 const struct ntb_transport_client *client; 266 int rc = -EINVAL; 267 268 get_device(dev); 269 270 client = drv_client(dev->driver); 271 rc = client->probe(dev); 272 if (rc) 273 put_device(dev); 274 275 return rc; 276} 277 278static int ntb_transport_bus_remove(struct device *dev) 279{ 280 const struct ntb_transport_client *client; 281 282 client = drv_client(dev->driver); 283 client->remove(dev); 284 285 put_device(dev); 286 287 return 0; 288} 289 290static struct bus_type ntb_transport_bus = { 291 .name = "ntb_transport", 292 .match = ntb_transport_bus_match, 293 .probe = ntb_transport_bus_probe, 294 .remove = ntb_transport_bus_remove, 295}; 296 297static LIST_HEAD(ntb_transport_list); 298 299static int ntb_bus_init(struct ntb_transport_ctx *nt) 300{ 301 list_add_tail(&nt->entry, &ntb_transport_list); 302 return 0; 303} 304 305static void ntb_bus_remove(struct ntb_transport_ctx *nt) 306{ 307 struct ntb_transport_client_dev *client_dev, *cd; 308 309 list_for_each_entry_safe(client_dev, cd, &nt->client_devs, entry) { 310 dev_err(client_dev->dev.parent, "%s still attached to bus, removing\n", 311 dev_name(&client_dev->dev)); 312 list_del(&client_dev->entry); 313 device_unregister(&client_dev->dev); 314 } 315 316 list_del(&nt->entry); 317} 318 319static void ntb_transport_client_release(struct device *dev) 320{ 321 struct ntb_transport_client_dev *client_dev; 322 323 client_dev = dev_client_dev(dev); 324 kfree(client_dev); 325} 326 327/** 328 * ntb_transport_unregister_client_dev - Unregister NTB client device 329 * @device_name: Name of NTB client device 330 * 331 * Unregister an NTB client device with the NTB transport layer 332 */ 333void ntb_transport_unregister_client_dev(char *device_name) 334{ 335 struct ntb_transport_client_dev *client, *cd; 336 struct ntb_transport_ctx *nt; 337 338 list_for_each_entry(nt, &ntb_transport_list, entry) 339 list_for_each_entry_safe(client, cd, &nt->client_devs, entry) 340 if (!strncmp(dev_name(&client->dev), device_name, 341 strlen(device_name))) { 342 list_del(&client->entry); 343 device_unregister(&client->dev); 344 } 345} 346EXPORT_SYMBOL_GPL(ntb_transport_unregister_client_dev); 347 348/** 349 * ntb_transport_register_client_dev - Register NTB client device 350 * @device_name: Name of NTB client device 351 * 352 * Register an NTB client device with the NTB transport layer 353 */ 354int ntb_transport_register_client_dev(char *device_name) 355{ 356 struct ntb_transport_client_dev *client_dev; 357 struct ntb_transport_ctx *nt; 358 int node; 359 int rc, i = 0; 360 361 if (list_empty(&ntb_transport_list)) 362 return -ENODEV; 363 364 list_for_each_entry(nt, &ntb_transport_list, entry) { 365 struct device *dev; 366 367 node = dev_to_node(&nt->ndev->dev); 368 369 client_dev = kzalloc_node(sizeof(*client_dev), 370 GFP_KERNEL, node); 371 if (!client_dev) { 372 rc = -ENOMEM; 373 goto err; 374 } 375 376 dev = &client_dev->dev; 377 378 /* setup and register client devices */ 379 dev_set_name(dev, "%s%d", device_name, i); 380 dev->bus = &ntb_transport_bus; 381 dev->release = ntb_transport_client_release; 382 dev->parent = &nt->ndev->dev; 383 384 rc = device_register(dev); 385 if (rc) { 386 kfree(client_dev); 387 goto err; 388 } 389 390 list_add_tail(&client_dev->entry, &nt->client_devs); 391 i++; 392 } 393 394 return 0; 395 396err: 397 ntb_transport_unregister_client_dev(device_name); 398 399 return rc; 400} 401EXPORT_SYMBOL_GPL(ntb_transport_register_client_dev); 402 403/** 404 * ntb_transport_register_client - Register NTB client driver 405 * @drv: NTB client driver to be registered 406 * 407 * Register an NTB client driver with the NTB transport layer 408 * 409 * RETURNS: An appropriate -ERRNO error value on error, or zero for success. 410 */ 411int ntb_transport_register_client(struct ntb_transport_client *drv) 412{ 413 drv->driver.bus = &ntb_transport_bus; 414 415 if (list_empty(&ntb_transport_list)) 416 return -ENODEV; 417 418 return driver_register(&drv->driver); 419} 420EXPORT_SYMBOL_GPL(ntb_transport_register_client); 421 422/** 423 * ntb_transport_unregister_client - Unregister NTB client driver 424 * @drv: NTB client driver to be unregistered 425 * 426 * Unregister an NTB client driver with the NTB transport layer 427 * 428 * RETURNS: An appropriate -ERRNO error value on error, or zero for success. 429 */ 430void ntb_transport_unregister_client(struct ntb_transport_client *drv) 431{ 432 driver_unregister(&drv->driver); 433} 434EXPORT_SYMBOL_GPL(ntb_transport_unregister_client); 435 436static ssize_t debugfs_read(struct file *filp, char __user *ubuf, size_t count, 437 loff_t *offp) 438{ 439 struct ntb_transport_qp *qp; 440 char *buf; 441 ssize_t ret, out_offset, out_count; 442 443 qp = filp->private_data; 444 445 if (!qp || !qp->link_is_up) 446 return 0; 447 448 out_count = 1000; 449 450 buf = kmalloc(out_count, GFP_KERNEL); 451 if (!buf) 452 return -ENOMEM; 453 454 out_offset = 0; 455 out_offset += snprintf(buf + out_offset, out_count - out_offset, 456 "\nNTB QP stats:\n\n"); 457 out_offset += snprintf(buf + out_offset, out_count - out_offset, 458 "rx_bytes - \t%llu\n", qp->rx_bytes); 459 out_offset += snprintf(buf + out_offset, out_count - out_offset, 460 "rx_pkts - \t%llu\n", qp->rx_pkts); 461 out_offset += snprintf(buf + out_offset, out_count - out_offset, 462 "rx_memcpy - \t%llu\n", qp->rx_memcpy); 463 out_offset += snprintf(buf + out_offset, out_count - out_offset, 464 "rx_async - \t%llu\n", qp->rx_async); 465 out_offset += snprintf(buf + out_offset, out_count - out_offset, 466 "rx_ring_empty - %llu\n", qp->rx_ring_empty); 467 out_offset += snprintf(buf + out_offset, out_count - out_offset, 468 "rx_err_no_buf - %llu\n", qp->rx_err_no_buf); 469 out_offset += snprintf(buf + out_offset, out_count - out_offset, 470 "rx_err_oflow - \t%llu\n", qp->rx_err_oflow); 471 out_offset += snprintf(buf + out_offset, out_count - out_offset, 472 "rx_err_ver - \t%llu\n", qp->rx_err_ver); 473 out_offset += snprintf(buf + out_offset, out_count - out_offset, 474 "rx_buff - \t0x%p\n", qp->rx_buff); 475 out_offset += snprintf(buf + out_offset, out_count - out_offset, 476 "rx_index - \t%u\n", qp->rx_index); 477 out_offset += snprintf(buf + out_offset, out_count - out_offset, 478 "rx_max_entry - \t%u\n\n", qp->rx_max_entry); 479 480 out_offset += snprintf(buf + out_offset, out_count - out_offset, 481 "tx_bytes - \t%llu\n", qp->tx_bytes); 482 out_offset += snprintf(buf + out_offset, out_count - out_offset, 483 "tx_pkts - \t%llu\n", qp->tx_pkts); 484 out_offset += snprintf(buf + out_offset, out_count - out_offset, 485 "tx_memcpy - \t%llu\n", qp->tx_memcpy); 486 out_offset += snprintf(buf + out_offset, out_count - out_offset, 487 "tx_async - \t%llu\n", qp->tx_async); 488 out_offset += snprintf(buf + out_offset, out_count - out_offset, 489 "tx_ring_full - \t%llu\n", qp->tx_ring_full); 490 out_offset += snprintf(buf + out_offset, out_count - out_offset, 491 "tx_err_no_buf - %llu\n", qp->tx_err_no_buf); 492 out_offset += snprintf(buf + out_offset, out_count - out_offset, 493 "tx_mw - \t0x%p\n", qp->tx_mw); 494 out_offset += snprintf(buf + out_offset, out_count - out_offset, 495 "tx_index (H) - \t%u\n", qp->tx_index); 496 out_offset += snprintf(buf + out_offset, out_count - out_offset, 497 "RRI (T) - \t%u\n", 498 qp->remote_rx_info->entry); 499 out_offset += snprintf(buf + out_offset, out_count - out_offset, 500 "tx_max_entry - \t%u\n", qp->tx_max_entry); 501 out_offset += snprintf(buf + out_offset, out_count - out_offset, 502 "free tx - \t%u\n", 503 ntb_transport_tx_free_entry(qp)); 504 505 out_offset += snprintf(buf + out_offset, out_count - out_offset, 506 "\n"); 507 out_offset += snprintf(buf + out_offset, out_count - out_offset, 508 "Using TX DMA - \t%s\n", 509 qp->tx_dma_chan ? "Yes" : "No"); 510 out_offset += snprintf(buf + out_offset, out_count - out_offset, 511 "Using RX DMA - \t%s\n", 512 qp->rx_dma_chan ? "Yes" : "No"); 513 out_offset += snprintf(buf + out_offset, out_count - out_offset, 514 "QP Link - \t%s\n", 515 qp->link_is_up ? "Up" : "Down"); 516 out_offset += snprintf(buf + out_offset, out_count - out_offset, 517 "\n"); 518 519 if (out_offset > out_count) 520 out_offset = out_count; 521 522 ret = simple_read_from_buffer(ubuf, count, offp, buf, out_offset); 523 kfree(buf); 524 return ret; 525} 526 527static const struct file_operations ntb_qp_debugfs_stats = { 528 .owner = THIS_MODULE, 529 .open = simple_open, 530 .read = debugfs_read, 531}; 532 533static void ntb_list_add(spinlock_t *lock, struct list_head *entry, 534 struct list_head *list) 535{ 536 unsigned long flags; 537 538 spin_lock_irqsave(lock, flags); 539 list_add_tail(entry, list); 540 spin_unlock_irqrestore(lock, flags); 541} 542 543static struct ntb_queue_entry *ntb_list_rm(spinlock_t *lock, 544 struct list_head *list) 545{ 546 struct ntb_queue_entry *entry; 547 unsigned long flags; 548 549 spin_lock_irqsave(lock, flags); 550 if (list_empty(list)) { 551 entry = NULL; 552 goto out; 553 } 554 entry = list_first_entry(list, struct ntb_queue_entry, entry); 555 list_del(&entry->entry); 556 557out: 558 spin_unlock_irqrestore(lock, flags); 559 560 return entry; 561} 562 563static struct ntb_queue_entry *ntb_list_mv(spinlock_t *lock, 564 struct list_head *list, 565 struct list_head *to_list) 566{ 567 struct ntb_queue_entry *entry; 568 unsigned long flags; 569 570 spin_lock_irqsave(lock, flags); 571 572 if (list_empty(list)) { 573 entry = NULL; 574 } else { 575 entry = list_first_entry(list, struct ntb_queue_entry, entry); 576 list_move_tail(&entry->entry, to_list); 577 } 578 579 spin_unlock_irqrestore(lock, flags); 580 581 return entry; 582} 583 584static int ntb_transport_setup_qp_mw(struct ntb_transport_ctx *nt, 585 unsigned int qp_num) 586{ 587 struct ntb_transport_qp *qp = &nt->qp_vec[qp_num]; 588 struct ntb_transport_mw *mw; 589 unsigned int rx_size, num_qps_mw; 590 unsigned int mw_num, mw_count, qp_count; 591 unsigned int i; 592 593 mw_count = nt->mw_count; 594 qp_count = nt->qp_count; 595 596 mw_num = QP_TO_MW(nt, qp_num); 597 mw = &nt->mw_vec[mw_num]; 598 599 if (!mw->virt_addr) 600 return -ENOMEM; 601 602 if (qp_count % mw_count && mw_num + 1 < qp_count / mw_count) 603 num_qps_mw = qp_count / mw_count + 1; 604 else 605 num_qps_mw = qp_count / mw_count; 606 607 rx_size = (unsigned int)mw->xlat_size / num_qps_mw; 608 qp->rx_buff = mw->virt_addr + rx_size * (qp_num / mw_count); 609 rx_size -= sizeof(struct ntb_rx_info); 610 611 qp->remote_rx_info = qp->rx_buff + rx_size; 612 613 /* Due to housekeeping, there must be atleast 2 buffs */ 614 qp->rx_max_frame = min(transport_mtu, rx_size / 2); 615 qp->rx_max_entry = rx_size / qp->rx_max_frame; 616 qp->rx_index = 0; 617 618 qp->remote_rx_info->entry = qp->rx_max_entry - 1; 619 620 /* setup the hdr offsets with 0's */ 621 for (i = 0; i < qp->rx_max_entry; i++) { 622 void *offset = (qp->rx_buff + qp->rx_max_frame * (i + 1) - 623 sizeof(struct ntb_payload_header)); 624 memset(offset, 0, sizeof(struct ntb_payload_header)); 625 } 626 627 qp->rx_pkts = 0; 628 qp->tx_pkts = 0; 629 qp->tx_index = 0; 630 631 return 0; 632} 633 634static void ntb_free_mw(struct ntb_transport_ctx *nt, int num_mw) 635{ 636 struct ntb_transport_mw *mw = &nt->mw_vec[num_mw]; 637 struct pci_dev *pdev = nt->ndev->pdev; 638 639 if (!mw->virt_addr) 640 return; 641 642 ntb_mw_clear_trans(nt->ndev, num_mw); 643 dma_free_coherent(&pdev->dev, mw->buff_size, 644 mw->virt_addr, mw->dma_addr); 645 mw->xlat_size = 0; 646 mw->buff_size = 0; 647 mw->virt_addr = NULL; 648} 649 650static int ntb_set_mw(struct ntb_transport_ctx *nt, int num_mw, 651 resource_size_t size) 652{ 653 struct ntb_transport_mw *mw = &nt->mw_vec[num_mw]; 654 struct pci_dev *pdev = nt->ndev->pdev; 655 size_t xlat_size, buff_size; 656 int rc; 657 658 if (!size) 659 return -EINVAL; 660 661 xlat_size = round_up(size, mw->xlat_align_size); 662 buff_size = round_up(size, mw->xlat_align); 663 664 /* No need to re-setup */ 665 if (mw->xlat_size == xlat_size) 666 return 0; 667 668 if (mw->buff_size) 669 ntb_free_mw(nt, num_mw); 670 671 /* Alloc memory for receiving data. Must be aligned */ 672 mw->xlat_size = xlat_size; 673 mw->buff_size = buff_size; 674 675 mw->virt_addr = dma_alloc_coherent(&pdev->dev, buff_size, 676 &mw->dma_addr, GFP_KERNEL); 677 if (!mw->virt_addr) { 678 mw->xlat_size = 0; 679 mw->buff_size = 0; 680 dev_err(&pdev->dev, "Unable to alloc MW buff of size %zu\n", 681 buff_size); 682 return -ENOMEM; 683 } 684 685 /* 686 * we must ensure that the memory address allocated is BAR size 687 * aligned in order for the XLAT register to take the value. This 688 * is a requirement of the hardware. It is recommended to setup CMA 689 * for BAR sizes equal or greater than 4MB. 690 */ 691 if (!IS_ALIGNED(mw->dma_addr, mw->xlat_align)) { 692 dev_err(&pdev->dev, "DMA memory %pad is not aligned\n", 693 &mw->dma_addr); 694 ntb_free_mw(nt, num_mw); 695 return -ENOMEM; 696 } 697 698 /* Notify HW the memory location of the receive buffer */ 699 rc = ntb_mw_set_trans(nt->ndev, num_mw, mw->dma_addr, mw->xlat_size); 700 if (rc) { 701 dev_err(&pdev->dev, "Unable to set mw%d translation", num_mw); 702 ntb_free_mw(nt, num_mw); 703 return -EIO; 704 } 705 706 return 0; 707} 708 709static void ntb_qp_link_down_reset(struct ntb_transport_qp *qp) 710{ 711 qp->link_is_up = false; 712 713 qp->tx_index = 0; 714 qp->rx_index = 0; 715 qp->rx_bytes = 0; 716 qp->rx_pkts = 0; 717 qp->rx_ring_empty = 0; 718 qp->rx_err_no_buf = 0; 719 qp->rx_err_oflow = 0; 720 qp->rx_err_ver = 0; 721 qp->rx_memcpy = 0; 722 qp->rx_async = 0; 723 qp->tx_bytes = 0; 724 qp->tx_pkts = 0; 725 qp->tx_ring_full = 0; 726 qp->tx_err_no_buf = 0; 727 qp->tx_memcpy = 0; 728 qp->tx_async = 0; 729} 730 731static void ntb_qp_link_cleanup(struct ntb_transport_qp *qp) 732{ 733 struct ntb_transport_ctx *nt = qp->transport; 734 struct pci_dev *pdev = nt->ndev->pdev; 735 736 dev_info(&pdev->dev, "qp %d: Link Cleanup\n", qp->qp_num); 737 738 cancel_delayed_work_sync(&qp->link_work); 739 ntb_qp_link_down_reset(qp); 740 741 if (qp->event_handler) 742 qp->event_handler(qp->cb_data, qp->link_is_up); 743} 744 745static void ntb_qp_link_cleanup_work(struct work_struct *work) 746{ 747 struct ntb_transport_qp *qp = container_of(work, 748 struct ntb_transport_qp, 749 link_cleanup); 750 struct ntb_transport_ctx *nt = qp->transport; 751 752 ntb_qp_link_cleanup(qp); 753 754 if (nt->link_is_up) 755 schedule_delayed_work(&qp->link_work, 756 msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT)); 757} 758 759static void ntb_qp_link_down(struct ntb_transport_qp *qp) 760{ 761 schedule_work(&qp->link_cleanup); 762} 763 764static void ntb_transport_link_cleanup(struct ntb_transport_ctx *nt) 765{ 766 struct ntb_transport_qp *qp; 767 u64 qp_bitmap_alloc; 768 int i; 769 770 qp_bitmap_alloc = nt->qp_bitmap & ~nt->qp_bitmap_free; 771 772 /* Pass along the info to any clients */ 773 for (i = 0; i < nt->qp_count; i++) 774 if (qp_bitmap_alloc & BIT_ULL(i)) { 775 qp = &nt->qp_vec[i]; 776 ntb_qp_link_cleanup(qp); 777 cancel_work_sync(&qp->link_cleanup); 778 cancel_delayed_work_sync(&qp->link_work); 779 } 780 781 if (!nt->link_is_up) 782 cancel_delayed_work_sync(&nt->link_work); 783 784 /* The scratchpad registers keep the values if the remote side 785 * goes down, blast them now to give them a sane value the next 786 * time they are accessed 787 */ 788 for (i = 0; i < MAX_SPAD; i++) 789 ntb_spad_write(nt->ndev, i, 0); 790} 791 792static void ntb_transport_link_cleanup_work(struct work_struct *work) 793{ 794 struct ntb_transport_ctx *nt = 795 container_of(work, struct ntb_transport_ctx, link_cleanup); 796 797 ntb_transport_link_cleanup(nt); 798} 799 800static void ntb_transport_event_callback(void *data) 801{ 802 struct ntb_transport_ctx *nt = data; 803 804 if (ntb_link_is_up(nt->ndev, NULL, NULL) == 1) 805 schedule_delayed_work(&nt->link_work, 0); 806 else 807 schedule_work(&nt->link_cleanup); 808} 809 810static void ntb_transport_link_work(struct work_struct *work) 811{ 812 struct ntb_transport_ctx *nt = 813 container_of(work, struct ntb_transport_ctx, link_work.work); 814 struct ntb_dev *ndev = nt->ndev; 815 struct pci_dev *pdev = ndev->pdev; 816 resource_size_t size; 817 u32 val; 818 int rc, i, spad; 819 820 /* send the local info, in the opposite order of the way we read it */ 821 for (i = 0; i < nt->mw_count; i++) { 822 size = nt->mw_vec[i].phys_size; 823 824 if (max_mw_size && size > max_mw_size) 825 size = max_mw_size; 826 827 spad = MW0_SZ_HIGH + (i * 2); 828 ntb_peer_spad_write(ndev, spad, upper_32_bits(size)); 829 830 spad = MW0_SZ_LOW + (i * 2); 831 ntb_peer_spad_write(ndev, spad, lower_32_bits(size)); 832 } 833 834 ntb_peer_spad_write(ndev, NUM_MWS, nt->mw_count); 835 836 ntb_peer_spad_write(ndev, NUM_QPS, nt->qp_count); 837 838 ntb_peer_spad_write(ndev, VERSION, NTB_TRANSPORT_VERSION); 839 840 /* Query the remote side for its info */ 841 val = ntb_spad_read(ndev, VERSION); 842 dev_dbg(&pdev->dev, "Remote version = %d\n", val); 843 if (val != NTB_TRANSPORT_VERSION) 844 goto out; 845 846 val = ntb_spad_read(ndev, NUM_QPS); 847 dev_dbg(&pdev->dev, "Remote max number of qps = %d\n", val); 848 if (val != nt->qp_count) 849 goto out; 850 851 val = ntb_spad_read(ndev, NUM_MWS); 852 dev_dbg(&pdev->dev, "Remote number of mws = %d\n", val); 853 if (val != nt->mw_count) 854 goto out; 855 856 for (i = 0; i < nt->mw_count; i++) { 857 u64 val64; 858 859 val = ntb_spad_read(ndev, MW0_SZ_HIGH + (i * 2)); 860 val64 = (u64)val << 32; 861 862 val = ntb_spad_read(ndev, MW0_SZ_LOW + (i * 2)); 863 val64 |= val; 864 865 dev_dbg(&pdev->dev, "Remote MW%d size = %#llx\n", i, val64); 866 867 rc = ntb_set_mw(nt, i, val64); 868 if (rc) 869 goto out1; 870 } 871 872 nt->link_is_up = true; 873 874 for (i = 0; i < nt->qp_count; i++) { 875 struct ntb_transport_qp *qp = &nt->qp_vec[i]; 876 877 ntb_transport_setup_qp_mw(nt, i); 878 879 if (qp->client_ready) 880 schedule_delayed_work(&qp->link_work, 0); 881 } 882 883 return; 884 885out1: 886 for (i = 0; i < nt->mw_count; i++) 887 ntb_free_mw(nt, i); 888out: 889 if (ntb_link_is_up(ndev, NULL, NULL) == 1) 890 schedule_delayed_work(&nt->link_work, 891 msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT)); 892} 893 894static void ntb_qp_link_work(struct work_struct *work) 895{ 896 struct ntb_transport_qp *qp = container_of(work, 897 struct ntb_transport_qp, 898 link_work.work); 899 struct pci_dev *pdev = qp->ndev->pdev; 900 struct ntb_transport_ctx *nt = qp->transport; 901 int val; 902 903 WARN_ON(!nt->link_is_up); 904 905 val = ntb_spad_read(nt->ndev, QP_LINKS); 906 907 ntb_peer_spad_write(nt->ndev, QP_LINKS, val | BIT(qp->qp_num)); 908 909 /* query remote spad for qp ready bits */ 910 ntb_peer_spad_read(nt->ndev, QP_LINKS); 911 dev_dbg_ratelimited(&pdev->dev, "Remote QP link status = %x\n", val); 912 913 /* See if the remote side is up */ 914 if (val & BIT(qp->qp_num)) { 915 dev_info(&pdev->dev, "qp %d: Link Up\n", qp->qp_num); 916 qp->link_is_up = true; 917 918 if (qp->event_handler) 919 qp->event_handler(qp->cb_data, qp->link_is_up); 920 921 tasklet_schedule(&qp->rxc_db_work); 922 } else if (nt->link_is_up) 923 schedule_delayed_work(&qp->link_work, 924 msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT)); 925} 926 927static int ntb_transport_init_queue(struct ntb_transport_ctx *nt, 928 unsigned int qp_num) 929{ 930 struct ntb_transport_qp *qp; 931 phys_addr_t mw_base; 932 resource_size_t mw_size; 933 unsigned int num_qps_mw, tx_size; 934 unsigned int mw_num, mw_count, qp_count; 935 u64 qp_offset; 936 937 mw_count = nt->mw_count; 938 qp_count = nt->qp_count; 939 940 mw_num = QP_TO_MW(nt, qp_num); 941 942 qp = &nt->qp_vec[qp_num]; 943 qp->qp_num = qp_num; 944 qp->transport = nt; 945 qp->ndev = nt->ndev; 946 qp->client_ready = false; 947 qp->event_handler = NULL; 948 ntb_qp_link_down_reset(qp); 949 950 if (qp_count % mw_count && mw_num + 1 < qp_count / mw_count) 951 num_qps_mw = qp_count / mw_count + 1; 952 else 953 num_qps_mw = qp_count / mw_count; 954 955 mw_base = nt->mw_vec[mw_num].phys_addr; 956 mw_size = nt->mw_vec[mw_num].phys_size; 957 958 tx_size = (unsigned int)mw_size / num_qps_mw; 959 qp_offset = tx_size * (qp_num / mw_count); 960 961 qp->tx_mw = nt->mw_vec[mw_num].vbase + qp_offset; 962 if (!qp->tx_mw) 963 return -EINVAL; 964 965 qp->tx_mw_phys = mw_base + qp_offset; 966 if (!qp->tx_mw_phys) 967 return -EINVAL; 968 969 tx_size -= sizeof(struct ntb_rx_info); 970 qp->rx_info = qp->tx_mw + tx_size; 971 972 /* Due to housekeeping, there must be atleast 2 buffs */ 973 qp->tx_max_frame = min(transport_mtu, tx_size / 2); 974 qp->tx_max_entry = tx_size / qp->tx_max_frame; 975 976 if (nt->debugfs_node_dir) { 977 char debugfs_name[4]; 978 979 snprintf(debugfs_name, 4, "qp%d", qp_num); 980 qp->debugfs_dir = debugfs_create_dir(debugfs_name, 981 nt->debugfs_node_dir); 982 983 qp->debugfs_stats = debugfs_create_file("stats", S_IRUSR, 984 qp->debugfs_dir, qp, 985 &ntb_qp_debugfs_stats); 986 } else { 987 qp->debugfs_dir = NULL; 988 qp->debugfs_stats = NULL; 989 } 990 991 INIT_DELAYED_WORK(&qp->link_work, ntb_qp_link_work); 992 INIT_WORK(&qp->link_cleanup, ntb_qp_link_cleanup_work); 993 994 spin_lock_init(&qp->ntb_rx_q_lock); 995 spin_lock_init(&qp->ntb_tx_free_q_lock); 996 997 INIT_LIST_HEAD(&qp->rx_post_q); 998 INIT_LIST_HEAD(&qp->rx_pend_q); 999 INIT_LIST_HEAD(&qp->rx_free_q); 1000 INIT_LIST_HEAD(&qp->tx_free_q); 1001 1002 tasklet_init(&qp->rxc_db_work, ntb_transport_rxc_db, 1003 (unsigned long)qp); 1004 1005 return 0; 1006} 1007 1008static int ntb_transport_probe(struct ntb_client *self, struct ntb_dev *ndev) 1009{ 1010 struct ntb_transport_ctx *nt; 1011 struct ntb_transport_mw *mw; 1012 unsigned int mw_count, qp_count; 1013 u64 qp_bitmap; 1014 int node; 1015 int rc, i; 1016 1017 if (ntb_db_is_unsafe(ndev)) 1018 dev_dbg(&ndev->dev, 1019 "doorbell is unsafe, proceed anyway...\n"); 1020 if (ntb_spad_is_unsafe(ndev)) 1021 dev_dbg(&ndev->dev, 1022 "scratchpad is unsafe, proceed anyway...\n"); 1023 1024 node = dev_to_node(&ndev->dev); 1025 1026 nt = kzalloc_node(sizeof(*nt), GFP_KERNEL, node); 1027 if (!nt) 1028 return -ENOMEM; 1029 1030 nt->ndev = ndev; 1031 1032 mw_count = ntb_mw_count(ndev); 1033 1034 nt->mw_count = mw_count; 1035 1036 nt->mw_vec = kzalloc_node(mw_count * sizeof(*nt->mw_vec), 1037 GFP_KERNEL, node); 1038 if (!nt->mw_vec) { 1039 rc = -ENOMEM; 1040 goto err; 1041 } 1042 1043 for (i = 0; i < mw_count; i++) { 1044 mw = &nt->mw_vec[i]; 1045 1046 rc = ntb_mw_get_range(ndev, i, &mw->phys_addr, &mw->phys_size, 1047 &mw->xlat_align, &mw->xlat_align_size); 1048 if (rc) 1049 goto err1; 1050 1051 mw->vbase = ioremap_wc(mw->phys_addr, mw->phys_size); 1052 if (!mw->vbase) { 1053 rc = -ENOMEM; 1054 goto err1; 1055 } 1056 1057 mw->buff_size = 0; 1058 mw->xlat_size = 0; 1059 mw->virt_addr = NULL; 1060 mw->dma_addr = 0; 1061 } 1062 1063 qp_bitmap = ntb_db_valid_mask(ndev); 1064 1065 qp_count = ilog2(qp_bitmap); 1066 if (max_num_clients && max_num_clients < qp_count) 1067 qp_count = max_num_clients; 1068 else if (mw_count < qp_count) 1069 qp_count = mw_count; 1070 1071 qp_bitmap &= BIT_ULL(qp_count) - 1; 1072 1073 nt->qp_count = qp_count; 1074 nt->qp_bitmap = qp_bitmap; 1075 nt->qp_bitmap_free = qp_bitmap; 1076 1077 nt->qp_vec = kzalloc_node(qp_count * sizeof(*nt->qp_vec), 1078 GFP_KERNEL, node); 1079 if (!nt->qp_vec) { 1080 rc = -ENOMEM; 1081 goto err1; 1082 } 1083 1084 if (nt_debugfs_dir) { 1085 nt->debugfs_node_dir = 1086 debugfs_create_dir(pci_name(ndev->pdev), 1087 nt_debugfs_dir); 1088 } 1089 1090 for (i = 0; i < qp_count; i++) { 1091 rc = ntb_transport_init_queue(nt, i); 1092 if (rc) 1093 goto err2; 1094 } 1095 1096 INIT_DELAYED_WORK(&nt->link_work, ntb_transport_link_work); 1097 INIT_WORK(&nt->link_cleanup, ntb_transport_link_cleanup_work); 1098 1099 rc = ntb_set_ctx(ndev, nt, &ntb_transport_ops); 1100 if (rc) 1101 goto err2; 1102 1103 INIT_LIST_HEAD(&nt->client_devs); 1104 rc = ntb_bus_init(nt); 1105 if (rc) 1106 goto err3; 1107 1108 nt->link_is_up = false; 1109 ntb_link_enable(ndev, NTB_SPEED_AUTO, NTB_WIDTH_AUTO); 1110 ntb_link_event(ndev); 1111 1112 return 0; 1113 1114err3: 1115 ntb_clear_ctx(ndev); 1116err2: 1117 kfree(nt->qp_vec); 1118err1: 1119 while (i--) { 1120 mw = &nt->mw_vec[i]; 1121 iounmap(mw->vbase); 1122 } 1123 kfree(nt->mw_vec); 1124err: 1125 kfree(nt); 1126 return rc; 1127} 1128 1129static void ntb_transport_free(struct ntb_client *self, struct ntb_dev *ndev) 1130{ 1131 struct ntb_transport_ctx *nt = ndev->ctx; 1132 struct ntb_transport_qp *qp; 1133 u64 qp_bitmap_alloc; 1134 int i; 1135 1136 ntb_transport_link_cleanup(nt); 1137 cancel_work_sync(&nt->link_cleanup); 1138 cancel_delayed_work_sync(&nt->link_work); 1139 1140 qp_bitmap_alloc = nt->qp_bitmap & ~nt->qp_bitmap_free; 1141 1142 /* verify that all the qp's are freed */ 1143 for (i = 0; i < nt->qp_count; i++) { 1144 qp = &nt->qp_vec[i]; 1145 if (qp_bitmap_alloc & BIT_ULL(i)) 1146 ntb_transport_free_queue(qp); 1147 debugfs_remove_recursive(qp->debugfs_dir); 1148 } 1149 1150 ntb_link_disable(ndev); 1151 ntb_clear_ctx(ndev); 1152 1153 ntb_bus_remove(nt); 1154 1155 for (i = nt->mw_count; i--; ) { 1156 ntb_free_mw(nt, i); 1157 iounmap(nt->mw_vec[i].vbase); 1158 } 1159 1160 kfree(nt->qp_vec); 1161 kfree(nt->mw_vec); 1162 kfree(nt); 1163} 1164 1165static void ntb_complete_rxc(struct ntb_transport_qp *qp) 1166{ 1167 struct ntb_queue_entry *entry; 1168 void *cb_data; 1169 unsigned int len; 1170 unsigned long irqflags; 1171 1172 spin_lock_irqsave(&qp->ntb_rx_q_lock, irqflags); 1173 1174 while (!list_empty(&qp->rx_post_q)) { 1175 entry = list_first_entry(&qp->rx_post_q, 1176 struct ntb_queue_entry, entry); 1177 if (!(entry->flags & DESC_DONE_FLAG)) 1178 break; 1179 1180 entry->rx_hdr->flags = 0; 1181 iowrite32(entry->index, &qp->rx_info->entry); 1182 1183 cb_data = entry->cb_data; 1184 len = entry->len; 1185 1186 list_move_tail(&entry->entry, &qp->rx_free_q); 1187 1188 spin_unlock_irqrestore(&qp->ntb_rx_q_lock, irqflags); 1189 1190 if (qp->rx_handler && qp->client_ready) 1191 qp->rx_handler(qp, qp->cb_data, cb_data, len); 1192 1193 spin_lock_irqsave(&qp->ntb_rx_q_lock, irqflags); 1194 } 1195 1196 spin_unlock_irqrestore(&qp->ntb_rx_q_lock, irqflags); 1197} 1198 1199static void ntb_rx_copy_callback(void *data) 1200{ 1201 struct ntb_queue_entry *entry = data; 1202 1203 entry->flags |= DESC_DONE_FLAG; 1204 1205 ntb_complete_rxc(entry->qp); 1206} 1207 1208static void ntb_memcpy_rx(struct ntb_queue_entry *entry, void *offset) 1209{ 1210 void *buf = entry->buf; 1211 size_t len = entry->len; 1212 1213 memcpy(buf, offset, len); 1214 1215 /* Ensure that the data is fully copied out before clearing the flag */ 1216 wmb(); 1217 1218 ntb_rx_copy_callback(entry); 1219} 1220 1221static void ntb_async_rx(struct ntb_queue_entry *entry, void *offset) 1222{ 1223 struct dma_async_tx_descriptor *txd; 1224 struct ntb_transport_qp *qp = entry->qp; 1225 struct dma_chan *chan = qp->rx_dma_chan; 1226 struct dma_device *device; 1227 size_t pay_off, buff_off, len; 1228 struct dmaengine_unmap_data *unmap; 1229 dma_cookie_t cookie; 1230 void *buf = entry->buf; 1231 1232 len = entry->len; 1233 1234 if (!chan) 1235 goto err; 1236 1237 if (len < copy_bytes) 1238 goto err; 1239 1240 device = chan->device; 1241 pay_off = (size_t)offset & ~PAGE_MASK; 1242 buff_off = (size_t)buf & ~PAGE_MASK; 1243 1244 if (!is_dma_copy_aligned(device, pay_off, buff_off, len)) 1245 goto err; 1246 1247 unmap = dmaengine_get_unmap_data(device->dev, 2, GFP_NOWAIT); 1248 if (!unmap) 1249 goto err; 1250 1251 unmap->len = len; 1252 unmap->addr[0] = dma_map_page(device->dev, virt_to_page(offset), 1253 pay_off, len, DMA_TO_DEVICE); 1254 if (dma_mapping_error(device->dev, unmap->addr[0])) 1255 goto err_get_unmap; 1256 1257 unmap->to_cnt = 1; 1258 1259 unmap->addr[1] = dma_map_page(device->dev, virt_to_page(buf), 1260 buff_off, len, DMA_FROM_DEVICE); 1261 if (dma_mapping_error(device->dev, unmap->addr[1])) 1262 goto err_get_unmap; 1263 1264 unmap->from_cnt = 1; 1265 1266 txd = device->device_prep_dma_memcpy(chan, unmap->addr[1], 1267 unmap->addr[0], len, 1268 DMA_PREP_INTERRUPT); 1269 if (!txd) 1270 goto err_get_unmap; 1271 1272 txd->callback = ntb_rx_copy_callback; 1273 txd->callback_param = entry; 1274 dma_set_unmap(txd, unmap); 1275 1276 cookie = dmaengine_submit(txd); 1277 if (dma_submit_error(cookie)) 1278 goto err_set_unmap; 1279 1280 dmaengine_unmap_put(unmap); 1281 1282 qp->last_cookie = cookie; 1283 1284 qp->rx_async++; 1285 1286 return; 1287 1288err_set_unmap: 1289 dmaengine_unmap_put(unmap); 1290err_get_unmap: 1291 dmaengine_unmap_put(unmap); 1292err: 1293 ntb_memcpy_rx(entry, offset); 1294 qp->rx_memcpy++; 1295} 1296 1297static int ntb_process_rxc(struct ntb_transport_qp *qp) 1298{ 1299 struct ntb_payload_header *hdr; 1300 struct ntb_queue_entry *entry; 1301 void *offset; 1302 1303 offset = qp->rx_buff + qp->rx_max_frame * qp->rx_index; 1304 hdr = offset + qp->rx_max_frame - sizeof(struct ntb_payload_header); 1305 1306 dev_dbg(&qp->ndev->pdev->dev, "qp %d: RX ver %u len %d flags %x\n", 1307 qp->qp_num, hdr->ver, hdr->len, hdr->flags); 1308 1309 if (!(hdr->flags & DESC_DONE_FLAG)) { 1310 dev_dbg(&qp->ndev->pdev->dev, "done flag not set\n"); 1311 qp->rx_ring_empty++; 1312 return -EAGAIN; 1313 } 1314 1315 if (hdr->flags & LINK_DOWN_FLAG) { 1316 dev_dbg(&qp->ndev->pdev->dev, "link down flag set\n"); 1317 ntb_qp_link_down(qp); 1318 hdr->flags = 0; 1319 return -EAGAIN; 1320 } 1321 1322 if (hdr->ver != (u32)qp->rx_pkts) { 1323 dev_dbg(&qp->ndev->pdev->dev, 1324 "version mismatch, expected %llu - got %u\n", 1325 qp->rx_pkts, hdr->ver); 1326 qp->rx_err_ver++; 1327 return -EIO; 1328 } 1329 1330 entry = ntb_list_mv(&qp->ntb_rx_q_lock, &qp->rx_pend_q, &qp->rx_post_q); 1331 if (!entry) { 1332 dev_dbg(&qp->ndev->pdev->dev, "no receive buffer\n"); 1333 qp->rx_err_no_buf++; 1334 return -EAGAIN; 1335 } 1336 1337 entry->rx_hdr = hdr; 1338 entry->index = qp->rx_index; 1339 1340 if (hdr->len > entry->len) { 1341 dev_dbg(&qp->ndev->pdev->dev, 1342 "receive buffer overflow! Wanted %d got %d\n", 1343 hdr->len, entry->len); 1344 qp->rx_err_oflow++; 1345 1346 entry->len = -EIO; 1347 entry->flags |= DESC_DONE_FLAG; 1348 1349 ntb_complete_rxc(qp); 1350 } else { 1351 dev_dbg(&qp->ndev->pdev->dev, 1352 "RX OK index %u ver %u size %d into buf size %d\n", 1353 qp->rx_index, hdr->ver, hdr->len, entry->len); 1354 1355 qp->rx_bytes += hdr->len; 1356 qp->rx_pkts++; 1357 1358 entry->len = hdr->len; 1359 1360 ntb_async_rx(entry, offset); 1361 } 1362 1363 qp->rx_index++; 1364 qp->rx_index %= qp->rx_max_entry; 1365 1366 return 0; 1367} 1368 1369static void ntb_transport_rxc_db(unsigned long data) 1370{ 1371 struct ntb_transport_qp *qp = (void *)data; 1372 int rc, i; 1373 1374 dev_dbg(&qp->ndev->pdev->dev, "%s: doorbell %d received\n", 1375 __func__, qp->qp_num); 1376 1377 /* Limit the number of packets processed in a single interrupt to 1378 * provide fairness to others 1379 */ 1380 for (i = 0; i < qp->rx_max_entry; i++) { 1381 rc = ntb_process_rxc(qp); 1382 if (rc) 1383 break; 1384 } 1385 1386 if (i && qp->rx_dma_chan) 1387 dma_async_issue_pending(qp->rx_dma_chan); 1388 1389 if (i == qp->rx_max_entry) { 1390 /* there is more work to do */ 1391 tasklet_schedule(&qp->rxc_db_work); 1392 } else if (ntb_db_read(qp->ndev) & BIT_ULL(qp->qp_num)) { 1393 /* the doorbell bit is set: clear it */ 1394 ntb_db_clear(qp->ndev, BIT_ULL(qp->qp_num)); 1395 /* ntb_db_read ensures ntb_db_clear write is committed */ 1396 ntb_db_read(qp->ndev); 1397 1398 /* an interrupt may have arrived between finishing 1399 * ntb_process_rxc and clearing the doorbell bit: 1400 * there might be some more work to do. 1401 */ 1402 tasklet_schedule(&qp->rxc_db_work); 1403 } 1404} 1405 1406static void ntb_tx_copy_callback(void *data) 1407{ 1408 struct ntb_queue_entry *entry = data; 1409 struct ntb_transport_qp *qp = entry->qp; 1410 struct ntb_payload_header __iomem *hdr = entry->tx_hdr; 1411 1412 iowrite32(entry->flags | DESC_DONE_FLAG, &hdr->flags); 1413 1414 ntb_peer_db_set(qp->ndev, BIT_ULL(qp->qp_num)); 1415 1416 /* The entry length can only be zero if the packet is intended to be a 1417 * "link down" or similar. Since no payload is being sent in these 1418 * cases, there is nothing to add to the completion queue. 1419 */ 1420 if (entry->len > 0) { 1421 qp->tx_bytes += entry->len; 1422 1423 if (qp->tx_handler) 1424 qp->tx_handler(qp, qp->cb_data, entry->cb_data, 1425 entry->len); 1426 } 1427 1428 ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, &qp->tx_free_q); 1429} 1430 1431static void ntb_memcpy_tx(struct ntb_queue_entry *entry, void __iomem *offset) 1432{ 1433#ifdef ARCH_HAS_NOCACHE_UACCESS 1434 /* 1435 * Using non-temporal mov to improve performance on non-cached 1436 * writes, even though we aren't actually copying from user space. 1437 */ 1438 __copy_from_user_inatomic_nocache(offset, entry->buf, entry->len); 1439#else 1440 memcpy_toio(offset, entry->buf, entry->len); 1441#endif 1442 1443 /* Ensure that the data is fully copied out before setting the flags */ 1444 wmb(); 1445 1446 ntb_tx_copy_callback(entry); 1447} 1448 1449static void ntb_async_tx(struct ntb_transport_qp *qp, 1450 struct ntb_queue_entry *entry) 1451{ 1452 struct ntb_payload_header __iomem *hdr; 1453 struct dma_async_tx_descriptor *txd; 1454 struct dma_chan *chan = qp->tx_dma_chan; 1455 struct dma_device *device; 1456 size_t dest_off, buff_off; 1457 struct dmaengine_unmap_data *unmap; 1458 dma_addr_t dest; 1459 dma_cookie_t cookie; 1460 void __iomem *offset; 1461 size_t len = entry->len; 1462 void *buf = entry->buf; 1463 1464 offset = qp->tx_mw + qp->tx_max_frame * qp->tx_index; 1465 hdr = offset + qp->tx_max_frame - sizeof(struct ntb_payload_header); 1466 entry->tx_hdr = hdr; 1467 1468 iowrite32(entry->len, &hdr->len); 1469 iowrite32((u32)qp->tx_pkts, &hdr->ver); 1470 1471 if (!chan) 1472 goto err; 1473 1474 if (len < copy_bytes) 1475 goto err; 1476 1477 device = chan->device; 1478 dest = qp->tx_mw_phys + qp->tx_max_frame * qp->tx_index; 1479 buff_off = (size_t)buf & ~PAGE_MASK; 1480 dest_off = (size_t)dest & ~PAGE_MASK; 1481 1482 if (!is_dma_copy_aligned(device, buff_off, dest_off, len)) 1483 goto err; 1484 1485 unmap = dmaengine_get_unmap_data(device->dev, 1, GFP_NOWAIT); 1486 if (!unmap) 1487 goto err; 1488 1489 unmap->len = len; 1490 unmap->addr[0] = dma_map_page(device->dev, virt_to_page(buf), 1491 buff_off, len, DMA_TO_DEVICE); 1492 if (dma_mapping_error(device->dev, unmap->addr[0])) 1493 goto err_get_unmap; 1494 1495 unmap->to_cnt = 1; 1496 1497 txd = device->device_prep_dma_memcpy(chan, dest, unmap->addr[0], len, 1498 DMA_PREP_INTERRUPT); 1499 if (!txd) 1500 goto err_get_unmap; 1501 1502 txd->callback = ntb_tx_copy_callback; 1503 txd->callback_param = entry; 1504 dma_set_unmap(txd, unmap); 1505 1506 cookie = dmaengine_submit(txd); 1507 if (dma_submit_error(cookie)) 1508 goto err_set_unmap; 1509 1510 dmaengine_unmap_put(unmap); 1511 1512 dma_async_issue_pending(chan); 1513 qp->tx_async++; 1514 1515 return; 1516err_set_unmap: 1517 dmaengine_unmap_put(unmap); 1518err_get_unmap: 1519 dmaengine_unmap_put(unmap); 1520err: 1521 ntb_memcpy_tx(entry, offset); 1522 qp->tx_memcpy++; 1523} 1524 1525static int ntb_process_tx(struct ntb_transport_qp *qp, 1526 struct ntb_queue_entry *entry) 1527{ 1528 if (qp->tx_index == qp->remote_rx_info->entry) { 1529 qp->tx_ring_full++; 1530 return -EAGAIN; 1531 } 1532 1533 if (entry->len > qp->tx_max_frame - sizeof(struct ntb_payload_header)) { 1534 if (qp->tx_handler) 1535 qp->tx_handler(qp->cb_data, qp, NULL, -EIO); 1536 1537 ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, 1538 &qp->tx_free_q); 1539 return 0; 1540 } 1541 1542 ntb_async_tx(qp, entry); 1543 1544 qp->tx_index++; 1545 qp->tx_index %= qp->tx_max_entry; 1546 1547 qp->tx_pkts++; 1548 1549 return 0; 1550} 1551 1552static void ntb_send_link_down(struct ntb_transport_qp *qp) 1553{ 1554 struct pci_dev *pdev = qp->ndev->pdev; 1555 struct ntb_queue_entry *entry; 1556 int i, rc; 1557 1558 if (!qp->link_is_up) 1559 return; 1560 1561 dev_info(&pdev->dev, "qp %d: Send Link Down\n", qp->qp_num); 1562 1563 for (i = 0; i < NTB_LINK_DOWN_TIMEOUT; i++) { 1564 entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q); 1565 if (entry) 1566 break; 1567 msleep(100); 1568 } 1569 1570 if (!entry) 1571 return; 1572 1573 entry->cb_data = NULL; 1574 entry->buf = NULL; 1575 entry->len = 0; 1576 entry->flags = LINK_DOWN_FLAG; 1577 1578 rc = ntb_process_tx(qp, entry); 1579 if (rc) 1580 dev_err(&pdev->dev, "ntb: QP%d unable to send linkdown msg\n", 1581 qp->qp_num); 1582 1583 ntb_qp_link_down_reset(qp); 1584} 1585 1586static bool ntb_dma_filter_fn(struct dma_chan *chan, void *node) 1587{ 1588 return dev_to_node(&chan->dev->device) == (int)(unsigned long)node; 1589} 1590 1591/** 1592 * ntb_transport_create_queue - Create a new NTB transport layer queue 1593 * @rx_handler: receive callback function 1594 * @tx_handler: transmit callback function 1595 * @event_handler: event callback function 1596 * 1597 * Create a new NTB transport layer queue and provide the queue with a callback 1598 * routine for both transmit and receive. The receive callback routine will be 1599 * used to pass up data when the transport has received it on the queue. The 1600 * transmit callback routine will be called when the transport has completed the 1601 * transmission of the data on the queue and the data is ready to be freed. 1602 * 1603 * RETURNS: pointer to newly created ntb_queue, NULL on error. 1604 */ 1605struct ntb_transport_qp * 1606ntb_transport_create_queue(void *data, struct device *client_dev, 1607 const struct ntb_queue_handlers *handlers) 1608{ 1609 struct ntb_dev *ndev; 1610 struct pci_dev *pdev; 1611 struct ntb_transport_ctx *nt; 1612 struct ntb_queue_entry *entry; 1613 struct ntb_transport_qp *qp; 1614 u64 qp_bit; 1615 unsigned int free_queue; 1616 dma_cap_mask_t dma_mask; 1617 int node; 1618 int i; 1619 1620 ndev = dev_ntb(client_dev->parent); 1621 pdev = ndev->pdev; 1622 nt = ndev->ctx; 1623 1624 node = dev_to_node(&ndev->dev); 1625 1626 free_queue = ffs(nt->qp_bitmap); 1627 if (!free_queue) 1628 goto err; 1629 1630 /* decrement free_queue to make it zero based */ 1631 free_queue--; 1632 1633 qp = &nt->qp_vec[free_queue]; 1634 qp_bit = BIT_ULL(qp->qp_num); 1635 1636 nt->qp_bitmap_free &= ~qp_bit; 1637 1638 qp->cb_data = data; 1639 qp->rx_handler = handlers->rx_handler; 1640 qp->tx_handler = handlers->tx_handler; 1641 qp->event_handler = handlers->event_handler; 1642 1643 dma_cap_zero(dma_mask); 1644 dma_cap_set(DMA_MEMCPY, dma_mask); 1645 1646 if (use_dma) { 1647 qp->tx_dma_chan = 1648 dma_request_channel(dma_mask, ntb_dma_filter_fn, 1649 (void *)(unsigned long)node); 1650 if (!qp->tx_dma_chan) 1651 dev_info(&pdev->dev, "Unable to allocate TX DMA channel\n"); 1652 1653 qp->rx_dma_chan = 1654 dma_request_channel(dma_mask, ntb_dma_filter_fn, 1655 (void *)(unsigned long)node); 1656 if (!qp->rx_dma_chan) 1657 dev_info(&pdev->dev, "Unable to allocate RX DMA channel\n"); 1658 } else { 1659 qp->tx_dma_chan = NULL; 1660 qp->rx_dma_chan = NULL; 1661 } 1662 1663 dev_dbg(&pdev->dev, "Using %s memcpy for TX\n", 1664 qp->tx_dma_chan ? "DMA" : "CPU"); 1665 1666 dev_dbg(&pdev->dev, "Using %s memcpy for RX\n", 1667 qp->rx_dma_chan ? "DMA" : "CPU"); 1668 1669 for (i = 0; i < NTB_QP_DEF_NUM_ENTRIES; i++) { 1670 entry = kzalloc_node(sizeof(*entry), GFP_ATOMIC, node); 1671 if (!entry) 1672 goto err1; 1673 1674 entry->qp = qp; 1675 ntb_list_add(&qp->ntb_rx_q_lock, &entry->entry, 1676 &qp->rx_free_q); 1677 } 1678 1679 for (i = 0; i < NTB_QP_DEF_NUM_ENTRIES; i++) { 1680 entry = kzalloc_node(sizeof(*entry), GFP_ATOMIC, node); 1681 if (!entry) 1682 goto err2; 1683 1684 entry->qp = qp; 1685 ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, 1686 &qp->tx_free_q); 1687 } 1688 1689 ntb_db_clear(qp->ndev, qp_bit); 1690 ntb_db_clear_mask(qp->ndev, qp_bit); 1691 1692 dev_info(&pdev->dev, "NTB Transport QP %d created\n", qp->qp_num); 1693 1694 return qp; 1695 1696err2: 1697 while ((entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q))) 1698 kfree(entry); 1699err1: 1700 while ((entry = ntb_list_rm(&qp->ntb_rx_q_lock, &qp->rx_free_q))) 1701 kfree(entry); 1702 if (qp->tx_dma_chan) 1703 dma_release_channel(qp->tx_dma_chan); 1704 if (qp->rx_dma_chan) 1705 dma_release_channel(qp->rx_dma_chan); 1706 nt->qp_bitmap_free |= qp_bit; 1707err: 1708 return NULL; 1709} 1710EXPORT_SYMBOL_GPL(ntb_transport_create_queue); 1711 1712/** 1713 * ntb_transport_free_queue - Frees NTB transport queue 1714 * @qp: NTB queue to be freed 1715 * 1716 * Frees NTB transport queue 1717 */ 1718void ntb_transport_free_queue(struct ntb_transport_qp *qp) 1719{ 1720 struct pci_dev *pdev; 1721 struct ntb_queue_entry *entry; 1722 u64 qp_bit; 1723 1724 if (!qp) 1725 return; 1726 1727 pdev = qp->ndev->pdev; 1728 1729 if (qp->tx_dma_chan) { 1730 struct dma_chan *chan = qp->tx_dma_chan; 1731 /* Putting the dma_chan to NULL will force any new traffic to be 1732 * processed by the CPU instead of the DAM engine 1733 */ 1734 qp->tx_dma_chan = NULL; 1735 1736 /* Try to be nice and wait for any queued DMA engine 1737 * transactions to process before smashing it with a rock 1738 */ 1739 dma_sync_wait(chan, qp->last_cookie); 1740 dmaengine_terminate_all(chan); 1741 dma_release_channel(chan); 1742 } 1743 1744 if (qp->rx_dma_chan) { 1745 struct dma_chan *chan = qp->rx_dma_chan; 1746 /* Putting the dma_chan to NULL will force any new traffic to be 1747 * processed by the CPU instead of the DAM engine 1748 */ 1749 qp->rx_dma_chan = NULL; 1750 1751 /* Try to be nice and wait for any queued DMA engine 1752 * transactions to process before smashing it with a rock 1753 */ 1754 dma_sync_wait(chan, qp->last_cookie); 1755 dmaengine_terminate_all(chan); 1756 dma_release_channel(chan); 1757 } 1758 1759 qp_bit = BIT_ULL(qp->qp_num); 1760 1761 ntb_db_set_mask(qp->ndev, qp_bit); 1762 tasklet_disable(&qp->rxc_db_work); 1763 1764 cancel_delayed_work_sync(&qp->link_work); 1765 1766 qp->cb_data = NULL; 1767 qp->rx_handler = NULL; 1768 qp->tx_handler = NULL; 1769 qp->event_handler = NULL; 1770 1771 while ((entry = ntb_list_rm(&qp->ntb_rx_q_lock, &qp->rx_free_q))) 1772 kfree(entry); 1773 1774 while ((entry = ntb_list_rm(&qp->ntb_rx_q_lock, &qp->rx_pend_q))) { 1775 dev_warn(&pdev->dev, "Freeing item from non-empty rx_pend_q\n"); 1776 kfree(entry); 1777 } 1778 1779 while ((entry = ntb_list_rm(&qp->ntb_rx_q_lock, &qp->rx_post_q))) { 1780 dev_warn(&pdev->dev, "Freeing item from non-empty rx_post_q\n"); 1781 kfree(entry); 1782 } 1783 1784 while ((entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q))) 1785 kfree(entry); 1786 1787 qp->transport->qp_bitmap_free |= qp_bit; 1788 1789 dev_info(&pdev->dev, "NTB Transport QP %d freed\n", qp->qp_num); 1790} 1791EXPORT_SYMBOL_GPL(ntb_transport_free_queue); 1792 1793/** 1794 * ntb_transport_rx_remove - Dequeues enqueued rx packet 1795 * @qp: NTB queue to be freed 1796 * @len: pointer to variable to write enqueued buffers length 1797 * 1798 * Dequeues unused buffers from receive queue. Should only be used during 1799 * shutdown of qp. 1800 * 1801 * RETURNS: NULL error value on error, or void* for success. 1802 */ 1803void *ntb_transport_rx_remove(struct ntb_transport_qp *qp, unsigned int *len) 1804{ 1805 struct ntb_queue_entry *entry; 1806 void *buf; 1807 1808 if (!qp || qp->client_ready) 1809 return NULL; 1810 1811 entry = ntb_list_rm(&qp->ntb_rx_q_lock, &qp->rx_pend_q); 1812 if (!entry) 1813 return NULL; 1814 1815 buf = entry->cb_data; 1816 *len = entry->len; 1817 1818 ntb_list_add(&qp->ntb_rx_q_lock, &entry->entry, &qp->rx_free_q); 1819 1820 return buf; 1821} 1822EXPORT_SYMBOL_GPL(ntb_transport_rx_remove); 1823 1824/** 1825 * ntb_transport_rx_enqueue - Enqueue a new NTB queue entry 1826 * @qp: NTB transport layer queue the entry is to be enqueued on 1827 * @cb: per buffer pointer for callback function to use 1828 * @data: pointer to data buffer that incoming packets will be copied into 1829 * @len: length of the data buffer 1830 * 1831 * Enqueue a new receive buffer onto the transport queue into which a NTB 1832 * payload can be received into. 1833 * 1834 * RETURNS: An appropriate -ERRNO error value on error, or zero for success. 1835 */ 1836int ntb_transport_rx_enqueue(struct ntb_transport_qp *qp, void *cb, void *data, 1837 unsigned int len) 1838{ 1839 struct ntb_queue_entry *entry; 1840 1841 if (!qp) 1842 return -EINVAL; 1843 1844 entry = ntb_list_rm(&qp->ntb_rx_q_lock, &qp->rx_free_q); 1845 if (!entry) 1846 return -ENOMEM; 1847 1848 entry->cb_data = cb; 1849 entry->buf = data; 1850 entry->len = len; 1851 entry->flags = 0; 1852 1853 ntb_list_add(&qp->ntb_rx_q_lock, &entry->entry, &qp->rx_pend_q); 1854 1855 tasklet_schedule(&qp->rxc_db_work); 1856 1857 return 0; 1858} 1859EXPORT_SYMBOL_GPL(ntb_transport_rx_enqueue); 1860 1861/** 1862 * ntb_transport_tx_enqueue - Enqueue a new NTB queue entry 1863 * @qp: NTB transport layer queue the entry is to be enqueued on 1864 * @cb: per buffer pointer for callback function to use 1865 * @data: pointer to data buffer that will be sent 1866 * @len: length of the data buffer 1867 * 1868 * Enqueue a new transmit buffer onto the transport queue from which a NTB 1869 * payload will be transmitted. This assumes that a lock is being held to 1870 * serialize access to the qp. 1871 * 1872 * RETURNS: An appropriate -ERRNO error value on error, or zero for success. 1873 */ 1874int ntb_transport_tx_enqueue(struct ntb_transport_qp *qp, void *cb, void *data, 1875 unsigned int len) 1876{ 1877 struct ntb_queue_entry *entry; 1878 int rc; 1879 1880 if (!qp || !qp->link_is_up || !len) 1881 return -EINVAL; 1882 1883 entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q); 1884 if (!entry) { 1885 qp->tx_err_no_buf++; 1886 return -EBUSY; 1887 } 1888 1889 entry->cb_data = cb; 1890 entry->buf = data; 1891 entry->len = len; 1892 entry->flags = 0; 1893 1894 rc = ntb_process_tx(qp, entry); 1895 if (rc) 1896 ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, 1897 &qp->tx_free_q); 1898 1899 return rc; 1900} 1901EXPORT_SYMBOL_GPL(ntb_transport_tx_enqueue); 1902 1903/** 1904 * ntb_transport_link_up - Notify NTB transport of client readiness to use queue 1905 * @qp: NTB transport layer queue to be enabled 1906 * 1907 * Notify NTB transport layer of client readiness to use queue 1908 */ 1909void ntb_transport_link_up(struct ntb_transport_qp *qp) 1910{ 1911 if (!qp) 1912 return; 1913 1914 qp->client_ready = true; 1915 1916 if (qp->transport->link_is_up) 1917 schedule_delayed_work(&qp->link_work, 0); 1918} 1919EXPORT_SYMBOL_GPL(ntb_transport_link_up); 1920 1921/** 1922 * ntb_transport_link_down - Notify NTB transport to no longer enqueue data 1923 * @qp: NTB transport layer queue to be disabled 1924 * 1925 * Notify NTB transport layer of client's desire to no longer receive data on 1926 * transport queue specified. It is the client's responsibility to ensure all 1927 * entries on queue are purged or otherwise handled appropriately. 1928 */ 1929void ntb_transport_link_down(struct ntb_transport_qp *qp) 1930{ 1931 int val; 1932 1933 if (!qp) 1934 return; 1935 1936 qp->client_ready = false; 1937 1938 val = ntb_spad_read(qp->ndev, QP_LINKS); 1939 1940 ntb_peer_spad_write(qp->ndev, QP_LINKS, 1941 val & ~BIT(qp->qp_num)); 1942 1943 if (qp->link_is_up) 1944 ntb_send_link_down(qp); 1945 else 1946 cancel_delayed_work_sync(&qp->link_work); 1947} 1948EXPORT_SYMBOL_GPL(ntb_transport_link_down); 1949 1950/** 1951 * ntb_transport_link_query - Query transport link state 1952 * @qp: NTB transport layer queue to be queried 1953 * 1954 * Query connectivity to the remote system of the NTB transport queue 1955 * 1956 * RETURNS: true for link up or false for link down 1957 */ 1958bool ntb_transport_link_query(struct ntb_transport_qp *qp) 1959{ 1960 if (!qp) 1961 return false; 1962 1963 return qp->link_is_up; 1964} 1965EXPORT_SYMBOL_GPL(ntb_transport_link_query); 1966 1967/** 1968 * ntb_transport_qp_num - Query the qp number 1969 * @qp: NTB transport layer queue to be queried 1970 * 1971 * Query qp number of the NTB transport queue 1972 * 1973 * RETURNS: a zero based number specifying the qp number 1974 */ 1975unsigned char ntb_transport_qp_num(struct ntb_transport_qp *qp) 1976{ 1977 if (!qp) 1978 return 0; 1979 1980 return qp->qp_num; 1981} 1982EXPORT_SYMBOL_GPL(ntb_transport_qp_num); 1983 1984/** 1985 * ntb_transport_max_size - Query the max payload size of a qp 1986 * @qp: NTB transport layer queue to be queried 1987 * 1988 * Query the maximum payload size permissible on the given qp 1989 * 1990 * RETURNS: the max payload size of a qp 1991 */ 1992unsigned int ntb_transport_max_size(struct ntb_transport_qp *qp) 1993{ 1994 unsigned int max_size; 1995 unsigned int copy_align; 1996 struct dma_chan *rx_chan, *tx_chan; 1997 1998 if (!qp) 1999 return 0; 2000 2001 rx_chan = qp->rx_dma_chan; 2002 tx_chan = qp->tx_dma_chan; 2003 2004 copy_align = max(rx_chan ? rx_chan->device->copy_align : 0, 2005 tx_chan ? tx_chan->device->copy_align : 0); 2006 2007 /* If DMA engine usage is possible, try to find the max size for that */ 2008 max_size = qp->tx_max_frame - sizeof(struct ntb_payload_header); 2009 max_size = round_down(max_size, 1 << copy_align); 2010 2011 return max_size; 2012} 2013EXPORT_SYMBOL_GPL(ntb_transport_max_size); 2014 2015unsigned int ntb_transport_tx_free_entry(struct ntb_transport_qp *qp) 2016{ 2017 unsigned int head = qp->tx_index; 2018 unsigned int tail = qp->remote_rx_info->entry; 2019 2020 return tail > head ? tail - head : qp->tx_max_entry + tail - head; 2021} 2022EXPORT_SYMBOL_GPL(ntb_transport_tx_free_entry); 2023 2024static void ntb_transport_doorbell_callback(void *data, int vector) 2025{ 2026 struct ntb_transport_ctx *nt = data; 2027 struct ntb_transport_qp *qp; 2028 u64 db_bits; 2029 unsigned int qp_num; 2030 2031 db_bits = (nt->qp_bitmap & ~nt->qp_bitmap_free & 2032 ntb_db_vector_mask(nt->ndev, vector)); 2033 2034 while (db_bits) { 2035 qp_num = __ffs(db_bits); 2036 qp = &nt->qp_vec[qp_num]; 2037 2038 tasklet_schedule(&qp->rxc_db_work); 2039 2040 db_bits &= ~BIT_ULL(qp_num); 2041 } 2042} 2043 2044static const struct ntb_ctx_ops ntb_transport_ops = { 2045 .link_event = ntb_transport_event_callback, 2046 .db_event = ntb_transport_doorbell_callback, 2047}; 2048 2049static struct ntb_client ntb_transport_client = { 2050 .ops = { 2051 .probe = ntb_transport_probe, 2052 .remove = ntb_transport_free, 2053 }, 2054}; 2055 2056static int __init ntb_transport_init(void) 2057{ 2058 int rc; 2059 2060 pr_info("%s, version %s\n", NTB_TRANSPORT_DESC, NTB_TRANSPORT_VER); 2061 2062 if (debugfs_initialized()) 2063 nt_debugfs_dir = debugfs_create_dir(KBUILD_MODNAME, NULL); 2064 2065 rc = bus_register(&ntb_transport_bus); 2066 if (rc) 2067 goto err_bus; 2068 2069 rc = ntb_register_client(&ntb_transport_client); 2070 if (rc) 2071 goto err_client; 2072 2073 return 0; 2074 2075err_client: 2076 bus_unregister(&ntb_transport_bus); 2077err_bus: 2078 debugfs_remove_recursive(nt_debugfs_dir); 2079 return rc; 2080} 2081module_init(ntb_transport_init); 2082 2083static void __exit ntb_transport_exit(void) 2084{ 2085 debugfs_remove_recursive(nt_debugfs_dir); 2086 2087 ntb_unregister_client(&ntb_transport_client); 2088 bus_unregister(&ntb_transport_bus); 2089} 2090module_exit(ntb_transport_exit); 2091