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 * 9 * This program is free software; you can redistribute it and/or modify 10 * it under the terms of version 2 of the GNU General Public License as 11 * published by the Free Software Foundation. 12 * 13 * BSD LICENSE 14 * 15 * Copyright(c) 2012 Intel Corporation. All rights reserved. 16 * 17 * Redistribution and use in source and binary forms, with or without 18 * modification, are permitted provided that the following conditions 19 * are met: 20 * 21 * * Redistributions of source code must retain the above copyright 22 * notice, this list of conditions and the following disclaimer. 23 * * Redistributions in binary form must reproduce the above copy 24 * notice, this list of conditions and the following disclaimer in 25 * the documentation and/or other materials provided with the 26 * distribution. 27 * * Neither the name of Intel Corporation nor the names of its 28 * contributors may be used to endorse or promote products derived 29 * from this software without specific prior written permission. 30 * 31 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 32 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 33 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 34 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 35 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 36 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 37 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 38 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 39 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 40 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 41 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 42 * 43 * Intel PCIe NTB Linux driver 44 * 45 * Contact Information: 46 * Jon Mason <jon.mason@intel.com> 47 */ 48#include <linux/debugfs.h> 49#include <linux/delay.h> 50#include <linux/dmaengine.h> 51#include <linux/dma-mapping.h> 52#include <linux/errno.h> 53#include <linux/export.h> 54#include <linux/interrupt.h> 55#include <linux/module.h> 56#include <linux/pci.h> 57#include <linux/slab.h> 58#include <linux/types.h> 59#include "ntb_hw.h" 60 61#define NTB_TRANSPORT_VERSION 3 62 63static unsigned int transport_mtu = 0x401E; 64module_param(transport_mtu, uint, 0644); 65MODULE_PARM_DESC(transport_mtu, "Maximum size of NTB transport packets"); 66 67static unsigned char max_num_clients; 68module_param(max_num_clients, byte, 0644); 69MODULE_PARM_DESC(max_num_clients, "Maximum number of NTB transport clients"); 70 71static unsigned int copy_bytes = 1024; 72module_param(copy_bytes, uint, 0644); 73MODULE_PARM_DESC(copy_bytes, "Threshold under which NTB will use the CPU to copy instead of DMA"); 74 75struct ntb_queue_entry { 76 /* ntb_queue list reference */ 77 struct list_head entry; 78 /* pointers to data to be transfered */ 79 void *cb_data; 80 void *buf; 81 unsigned int len; 82 unsigned int flags; 83 84 struct ntb_transport_qp *qp; 85 union { 86 struct ntb_payload_header __iomem *tx_hdr; 87 struct ntb_payload_header *rx_hdr; 88 }; 89 unsigned int index; 90}; 91 92struct ntb_rx_info { 93 unsigned int entry; 94}; 95 96struct ntb_transport_qp { 97 struct ntb_transport *transport; 98 struct ntb_device *ndev; 99 void *cb_data; 100 struct dma_chan *dma_chan; 101 102 bool client_ready; 103 bool qp_link; 104 u8 qp_num; /* Only 64 QP's are allowed. 0-63 */ 105 106 struct ntb_rx_info __iomem *rx_info; 107 struct ntb_rx_info *remote_rx_info; 108 109 void (*tx_handler)(struct ntb_transport_qp *qp, void *qp_data, 110 void *data, int len); 111 struct list_head tx_free_q; 112 spinlock_t ntb_tx_free_q_lock; 113 void __iomem *tx_mw; 114 dma_addr_t tx_mw_phys; 115 unsigned int tx_index; 116 unsigned int tx_max_entry; 117 unsigned int tx_max_frame; 118 119 void (*rx_handler)(struct ntb_transport_qp *qp, void *qp_data, 120 void *data, int len); 121 struct list_head rx_pend_q; 122 struct list_head rx_free_q; 123 spinlock_t ntb_rx_pend_q_lock; 124 spinlock_t ntb_rx_free_q_lock; 125 void *rx_buff; 126 unsigned int rx_index; 127 unsigned int rx_max_entry; 128 unsigned int rx_max_frame; 129 dma_cookie_t last_cookie; 130 131 void (*event_handler)(void *data, int status); 132 struct delayed_work link_work; 133 struct work_struct link_cleanup; 134 135 struct dentry *debugfs_dir; 136 struct dentry *debugfs_stats; 137 138 /* Stats */ 139 u64 rx_bytes; 140 u64 rx_pkts; 141 u64 rx_ring_empty; 142 u64 rx_err_no_buf; 143 u64 rx_err_oflow; 144 u64 rx_err_ver; 145 u64 rx_memcpy; 146 u64 rx_async; 147 u64 tx_bytes; 148 u64 tx_pkts; 149 u64 tx_ring_full; 150 u64 tx_err_no_buf; 151 u64 tx_memcpy; 152 u64 tx_async; 153}; 154 155struct ntb_transport_mw { 156 size_t size; 157 void *virt_addr; 158 dma_addr_t dma_addr; 159}; 160 161struct ntb_transport_client_dev { 162 struct list_head entry; 163 struct device dev; 164}; 165 166struct ntb_transport { 167 struct list_head entry; 168 struct list_head client_devs; 169 170 struct ntb_device *ndev; 171 struct ntb_transport_mw *mw; 172 struct ntb_transport_qp *qps; 173 unsigned int max_qps; 174 unsigned long qp_bitmap; 175 bool transport_link; 176 struct delayed_work link_work; 177 struct work_struct link_cleanup; 178}; 179 180enum { 181 DESC_DONE_FLAG = 1 << 0, 182 LINK_DOWN_FLAG = 1 << 1, 183}; 184 185struct ntb_payload_header { 186 unsigned int ver; 187 unsigned int len; 188 unsigned int flags; 189}; 190 191enum { 192 VERSION = 0, 193 QP_LINKS, 194 NUM_QPS, 195 NUM_MWS, 196 MW0_SZ_HIGH, 197 MW0_SZ_LOW, 198 MW1_SZ_HIGH, 199 MW1_SZ_LOW, 200 MAX_SPAD, 201}; 202 203#define QP_TO_MW(ndev, qp) ((qp) % ntb_max_mw(ndev)) 204#define NTB_QP_DEF_NUM_ENTRIES 100 205#define NTB_LINK_DOWN_TIMEOUT 10 206 207static int ntb_match_bus(struct device *dev, struct device_driver *drv) 208{ 209 return !strncmp(dev_name(dev), drv->name, strlen(drv->name)); 210} 211 212static int ntb_client_probe(struct device *dev) 213{ 214 const struct ntb_client *drv = container_of(dev->driver, 215 struct ntb_client, driver); 216 struct pci_dev *pdev = container_of(dev->parent, struct pci_dev, dev); 217 int rc = -EINVAL; 218 219 get_device(dev); 220 if (drv && drv->probe) 221 rc = drv->probe(pdev); 222 if (rc) 223 put_device(dev); 224 225 return rc; 226} 227 228static int ntb_client_remove(struct device *dev) 229{ 230 const struct ntb_client *drv = container_of(dev->driver, 231 struct ntb_client, driver); 232 struct pci_dev *pdev = container_of(dev->parent, struct pci_dev, dev); 233 234 if (drv && drv->remove) 235 drv->remove(pdev); 236 237 put_device(dev); 238 239 return 0; 240} 241 242static struct bus_type ntb_bus_type = { 243 .name = "ntb_bus", 244 .match = ntb_match_bus, 245 .probe = ntb_client_probe, 246 .remove = ntb_client_remove, 247}; 248 249static LIST_HEAD(ntb_transport_list); 250 251static int ntb_bus_init(struct ntb_transport *nt) 252{ 253 if (list_empty(&ntb_transport_list)) { 254 int rc = bus_register(&ntb_bus_type); 255 if (rc) 256 return rc; 257 } 258 259 list_add(&nt->entry, &ntb_transport_list); 260 261 return 0; 262} 263 264static void ntb_bus_remove(struct ntb_transport *nt) 265{ 266 struct ntb_transport_client_dev *client_dev, *cd; 267 268 list_for_each_entry_safe(client_dev, cd, &nt->client_devs, entry) { 269 dev_err(client_dev->dev.parent, "%s still attached to bus, removing\n", 270 dev_name(&client_dev->dev)); 271 list_del(&client_dev->entry); 272 device_unregister(&client_dev->dev); 273 } 274 275 list_del(&nt->entry); 276 277 if (list_empty(&ntb_transport_list)) 278 bus_unregister(&ntb_bus_type); 279} 280 281static void ntb_client_release(struct device *dev) 282{ 283 struct ntb_transport_client_dev *client_dev; 284 client_dev = container_of(dev, struct ntb_transport_client_dev, dev); 285 286 kfree(client_dev); 287} 288 289/** 290 * ntb_unregister_client_dev - Unregister NTB client device 291 * @device_name: Name of NTB client device 292 * 293 * Unregister an NTB client device with the NTB transport layer 294 */ 295void ntb_unregister_client_dev(char *device_name) 296{ 297 struct ntb_transport_client_dev *client, *cd; 298 struct ntb_transport *nt; 299 300 list_for_each_entry(nt, &ntb_transport_list, entry) 301 list_for_each_entry_safe(client, cd, &nt->client_devs, entry) 302 if (!strncmp(dev_name(&client->dev), device_name, 303 strlen(device_name))) { 304 list_del(&client->entry); 305 device_unregister(&client->dev); 306 } 307} 308EXPORT_SYMBOL_GPL(ntb_unregister_client_dev); 309 310/** 311 * ntb_register_client_dev - Register NTB client device 312 * @device_name: Name of NTB client device 313 * 314 * Register an NTB client device with the NTB transport layer 315 */ 316int ntb_register_client_dev(char *device_name) 317{ 318 struct ntb_transport_client_dev *client_dev; 319 struct ntb_transport *nt; 320 int rc, i = 0; 321 322 if (list_empty(&ntb_transport_list)) 323 return -ENODEV; 324 325 list_for_each_entry(nt, &ntb_transport_list, entry) { 326 struct device *dev; 327 328 client_dev = kzalloc(sizeof(struct ntb_transport_client_dev), 329 GFP_KERNEL); 330 if (!client_dev) { 331 rc = -ENOMEM; 332 goto err; 333 } 334 335 dev = &client_dev->dev; 336 337 /* setup and register client devices */ 338 dev_set_name(dev, "%s%d", device_name, i); 339 dev->bus = &ntb_bus_type; 340 dev->release = ntb_client_release; 341 dev->parent = &ntb_query_pdev(nt->ndev)->dev; 342 343 rc = device_register(dev); 344 if (rc) { 345 kfree(client_dev); 346 goto err; 347 } 348 349 list_add_tail(&client_dev->entry, &nt->client_devs); 350 i++; 351 } 352 353 return 0; 354 355err: 356 ntb_unregister_client_dev(device_name); 357 358 return rc; 359} 360EXPORT_SYMBOL_GPL(ntb_register_client_dev); 361 362/** 363 * ntb_register_client - Register NTB client driver 364 * @drv: NTB client driver to be registered 365 * 366 * Register an NTB client driver with the NTB transport layer 367 * 368 * RETURNS: An appropriate -ERRNO error value on error, or zero for success. 369 */ 370int ntb_register_client(struct ntb_client *drv) 371{ 372 drv->driver.bus = &ntb_bus_type; 373 374 if (list_empty(&ntb_transport_list)) 375 return -ENODEV; 376 377 return driver_register(&drv->driver); 378} 379EXPORT_SYMBOL_GPL(ntb_register_client); 380 381/** 382 * ntb_unregister_client - Unregister NTB client driver 383 * @drv: NTB client driver to be unregistered 384 * 385 * Unregister an NTB client driver with the NTB transport layer 386 * 387 * RETURNS: An appropriate -ERRNO error value on error, or zero for success. 388 */ 389void ntb_unregister_client(struct ntb_client *drv) 390{ 391 driver_unregister(&drv->driver); 392} 393EXPORT_SYMBOL_GPL(ntb_unregister_client); 394 395static ssize_t debugfs_read(struct file *filp, char __user *ubuf, size_t count, 396 loff_t *offp) 397{ 398 struct ntb_transport_qp *qp; 399 char *buf; 400 ssize_t ret, out_offset, out_count; 401 402 out_count = 1000; 403 404 buf = kmalloc(out_count, GFP_KERNEL); 405 if (!buf) 406 return -ENOMEM; 407 408 qp = filp->private_data; 409 out_offset = 0; 410 out_offset += snprintf(buf + out_offset, out_count - out_offset, 411 "NTB QP stats\n"); 412 out_offset += snprintf(buf + out_offset, out_count - out_offset, 413 "rx_bytes - \t%llu\n", qp->rx_bytes); 414 out_offset += snprintf(buf + out_offset, out_count - out_offset, 415 "rx_pkts - \t%llu\n", qp->rx_pkts); 416 out_offset += snprintf(buf + out_offset, out_count - out_offset, 417 "rx_memcpy - \t%llu\n", qp->rx_memcpy); 418 out_offset += snprintf(buf + out_offset, out_count - out_offset, 419 "rx_async - \t%llu\n", qp->rx_async); 420 out_offset += snprintf(buf + out_offset, out_count - out_offset, 421 "rx_ring_empty - %llu\n", qp->rx_ring_empty); 422 out_offset += snprintf(buf + out_offset, out_count - out_offset, 423 "rx_err_no_buf - %llu\n", qp->rx_err_no_buf); 424 out_offset += snprintf(buf + out_offset, out_count - out_offset, 425 "rx_err_oflow - \t%llu\n", qp->rx_err_oflow); 426 out_offset += snprintf(buf + out_offset, out_count - out_offset, 427 "rx_err_ver - \t%llu\n", qp->rx_err_ver); 428 out_offset += snprintf(buf + out_offset, out_count - out_offset, 429 "rx_buff - \t%p\n", qp->rx_buff); 430 out_offset += snprintf(buf + out_offset, out_count - out_offset, 431 "rx_index - \t%u\n", qp->rx_index); 432 out_offset += snprintf(buf + out_offset, out_count - out_offset, 433 "rx_max_entry - \t%u\n", qp->rx_max_entry); 434 435 out_offset += snprintf(buf + out_offset, out_count - out_offset, 436 "tx_bytes - \t%llu\n", qp->tx_bytes); 437 out_offset += snprintf(buf + out_offset, out_count - out_offset, 438 "tx_pkts - \t%llu\n", qp->tx_pkts); 439 out_offset += snprintf(buf + out_offset, out_count - out_offset, 440 "tx_memcpy - \t%llu\n", qp->tx_memcpy); 441 out_offset += snprintf(buf + out_offset, out_count - out_offset, 442 "tx_async - \t%llu\n", qp->tx_async); 443 out_offset += snprintf(buf + out_offset, out_count - out_offset, 444 "tx_ring_full - \t%llu\n", qp->tx_ring_full); 445 out_offset += snprintf(buf + out_offset, out_count - out_offset, 446 "tx_err_no_buf - %llu\n", qp->tx_err_no_buf); 447 out_offset += snprintf(buf + out_offset, out_count - out_offset, 448 "tx_mw - \t%p\n", qp->tx_mw); 449 out_offset += snprintf(buf + out_offset, out_count - out_offset, 450 "tx_index - \t%u\n", qp->tx_index); 451 out_offset += snprintf(buf + out_offset, out_count - out_offset, 452 "tx_max_entry - \t%u\n", qp->tx_max_entry); 453 454 out_offset += snprintf(buf + out_offset, out_count - out_offset, 455 "\nQP Link %s\n", (qp->qp_link == NTB_LINK_UP) ? 456 "Up" : "Down"); 457 if (out_offset > out_count) 458 out_offset = out_count; 459 460 ret = simple_read_from_buffer(ubuf, count, offp, buf, out_offset); 461 kfree(buf); 462 return ret; 463} 464 465static const struct file_operations ntb_qp_debugfs_stats = { 466 .owner = THIS_MODULE, 467 .open = simple_open, 468 .read = debugfs_read, 469}; 470 471static void ntb_list_add(spinlock_t *lock, struct list_head *entry, 472 struct list_head *list) 473{ 474 unsigned long flags; 475 476 spin_lock_irqsave(lock, flags); 477 list_add_tail(entry, list); 478 spin_unlock_irqrestore(lock, flags); 479} 480 481static struct ntb_queue_entry *ntb_list_rm(spinlock_t *lock, 482 struct list_head *list) 483{ 484 struct ntb_queue_entry *entry; 485 unsigned long flags; 486 487 spin_lock_irqsave(lock, flags); 488 if (list_empty(list)) { 489 entry = NULL; 490 goto out; 491 } 492 entry = list_first_entry(list, struct ntb_queue_entry, entry); 493 list_del(&entry->entry); 494out: 495 spin_unlock_irqrestore(lock, flags); 496 497 return entry; 498} 499 500static void ntb_transport_setup_qp_mw(struct ntb_transport *nt, 501 unsigned int qp_num) 502{ 503 struct ntb_transport_qp *qp = &nt->qps[qp_num]; 504 unsigned int rx_size, num_qps_mw; 505 u8 mw_num, mw_max; 506 unsigned int i; 507 508 mw_max = ntb_max_mw(nt->ndev); 509 mw_num = QP_TO_MW(nt->ndev, qp_num); 510 511 WARN_ON(nt->mw[mw_num].virt_addr == NULL); 512 513 if (nt->max_qps % mw_max && mw_num + 1 < nt->max_qps / mw_max) 514 num_qps_mw = nt->max_qps / mw_max + 1; 515 else 516 num_qps_mw = nt->max_qps / mw_max; 517 518 rx_size = (unsigned int) nt->mw[mw_num].size / num_qps_mw; 519 qp->rx_buff = nt->mw[mw_num].virt_addr + qp_num / mw_max * rx_size; 520 rx_size -= sizeof(struct ntb_rx_info); 521 522 qp->remote_rx_info = qp->rx_buff + rx_size; 523 524 /* Due to housekeeping, there must be atleast 2 buffs */ 525 qp->rx_max_frame = min(transport_mtu, rx_size / 2); 526 qp->rx_max_entry = rx_size / qp->rx_max_frame; 527 qp->rx_index = 0; 528 529 qp->remote_rx_info->entry = qp->rx_max_entry - 1; 530 531 /* setup the hdr offsets with 0's */ 532 for (i = 0; i < qp->rx_max_entry; i++) { 533 void *offset = qp->rx_buff + qp->rx_max_frame * (i + 1) - 534 sizeof(struct ntb_payload_header); 535 memset(offset, 0, sizeof(struct ntb_payload_header)); 536 } 537 538 qp->rx_pkts = 0; 539 qp->tx_pkts = 0; 540 qp->tx_index = 0; 541} 542 543static void ntb_free_mw(struct ntb_transport *nt, int num_mw) 544{ 545 struct ntb_transport_mw *mw = &nt->mw[num_mw]; 546 struct pci_dev *pdev = ntb_query_pdev(nt->ndev); 547 548 if (!mw->virt_addr) 549 return; 550 551 dma_free_coherent(&pdev->dev, mw->size, mw->virt_addr, mw->dma_addr); 552 mw->virt_addr = NULL; 553} 554 555static int ntb_set_mw(struct ntb_transport *nt, int num_mw, unsigned int size) 556{ 557 struct ntb_transport_mw *mw = &nt->mw[num_mw]; 558 struct pci_dev *pdev = ntb_query_pdev(nt->ndev); 559 560 /* No need to re-setup */ 561 if (mw->size == ALIGN(size, 4096)) 562 return 0; 563 564 if (mw->size != 0) 565 ntb_free_mw(nt, num_mw); 566 567 /* Alloc memory for receiving data. Must be 4k aligned */ 568 mw->size = ALIGN(size, 4096); 569 570 mw->virt_addr = dma_alloc_coherent(&pdev->dev, mw->size, &mw->dma_addr, 571 GFP_KERNEL); 572 if (!mw->virt_addr) { 573 mw->size = 0; 574 dev_err(&pdev->dev, "Unable to allocate MW buffer of size %d\n", 575 (int) mw->size); 576 return -ENOMEM; 577 } 578 579 /* 580 * we must ensure that the memory address allocated is BAR size 581 * aligned in order for the XLAT register to take the value. This 582 * is a requirement of the hardware. It is recommended to setup CMA 583 * for BAR sizes equal or greater than 4MB. 584 */ 585 if (!IS_ALIGNED(mw->dma_addr, mw->size)) { 586 dev_err(&pdev->dev, "DMA memory %pad not aligned to BAR size\n", 587 &mw->dma_addr); 588 ntb_free_mw(nt, num_mw); 589 return -ENOMEM; 590 } 591 592 /* Notify HW the memory location of the receive buffer */ 593 ntb_set_mw_addr(nt->ndev, num_mw, mw->dma_addr); 594 595 return 0; 596} 597 598static void ntb_qp_link_cleanup(struct ntb_transport_qp *qp) 599{ 600 struct ntb_transport *nt = qp->transport; 601 struct pci_dev *pdev = ntb_query_pdev(nt->ndev); 602 603 if (qp->qp_link == NTB_LINK_DOWN) { 604 cancel_delayed_work_sync(&qp->link_work); 605 return; 606 } 607 608 if (qp->event_handler) 609 qp->event_handler(qp->cb_data, NTB_LINK_DOWN); 610 611 dev_info(&pdev->dev, "qp %d: Link Down\n", qp->qp_num); 612 qp->qp_link = NTB_LINK_DOWN; 613} 614 615static void ntb_qp_link_cleanup_work(struct work_struct *work) 616{ 617 struct ntb_transport_qp *qp = container_of(work, 618 struct ntb_transport_qp, 619 link_cleanup); 620 struct ntb_transport *nt = qp->transport; 621 622 ntb_qp_link_cleanup(qp); 623 624 if (nt->transport_link == NTB_LINK_UP) 625 schedule_delayed_work(&qp->link_work, 626 msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT)); 627} 628 629static void ntb_qp_link_down(struct ntb_transport_qp *qp) 630{ 631 schedule_work(&qp->link_cleanup); 632} 633 634static void ntb_transport_link_cleanup(struct ntb_transport *nt) 635{ 636 int i; 637 638 /* Pass along the info to any clients */ 639 for (i = 0; i < nt->max_qps; i++) 640 if (!test_bit(i, &nt->qp_bitmap)) 641 ntb_qp_link_cleanup(&nt->qps[i]); 642 643 if (nt->transport_link == NTB_LINK_DOWN) 644 cancel_delayed_work_sync(&nt->link_work); 645 else 646 nt->transport_link = NTB_LINK_DOWN; 647 648 /* The scratchpad registers keep the values if the remote side 649 * goes down, blast them now to give them a sane value the next 650 * time they are accessed 651 */ 652 for (i = 0; i < MAX_SPAD; i++) 653 ntb_write_local_spad(nt->ndev, i, 0); 654} 655 656static void ntb_transport_link_cleanup_work(struct work_struct *work) 657{ 658 struct ntb_transport *nt = container_of(work, struct ntb_transport, 659 link_cleanup); 660 661 ntb_transport_link_cleanup(nt); 662} 663 664static void ntb_transport_event_callback(void *data, enum ntb_hw_event event) 665{ 666 struct ntb_transport *nt = data; 667 668 switch (event) { 669 case NTB_EVENT_HW_LINK_UP: 670 schedule_delayed_work(&nt->link_work, 0); 671 break; 672 case NTB_EVENT_HW_LINK_DOWN: 673 schedule_work(&nt->link_cleanup); 674 break; 675 default: 676 BUG(); 677 } 678} 679 680static void ntb_transport_link_work(struct work_struct *work) 681{ 682 struct ntb_transport *nt = container_of(work, struct ntb_transport, 683 link_work.work); 684 struct ntb_device *ndev = nt->ndev; 685 struct pci_dev *pdev = ntb_query_pdev(ndev); 686 u32 val; 687 int rc, i; 688 689 /* send the local info, in the opposite order of the way we read it */ 690 for (i = 0; i < ntb_max_mw(ndev); i++) { 691 rc = ntb_write_remote_spad(ndev, MW0_SZ_HIGH + (i * 2), 692 ntb_get_mw_size(ndev, i) >> 32); 693 if (rc) { 694 dev_err(&pdev->dev, "Error writing %u to remote spad %d\n", 695 (u32)(ntb_get_mw_size(ndev, i) >> 32), 696 MW0_SZ_HIGH + (i * 2)); 697 goto out; 698 } 699 700 rc = ntb_write_remote_spad(ndev, MW0_SZ_LOW + (i * 2), 701 (u32) ntb_get_mw_size(ndev, i)); 702 if (rc) { 703 dev_err(&pdev->dev, "Error writing %u to remote spad %d\n", 704 (u32) ntb_get_mw_size(ndev, i), 705 MW0_SZ_LOW + (i * 2)); 706 goto out; 707 } 708 } 709 710 rc = ntb_write_remote_spad(ndev, NUM_MWS, ntb_max_mw(ndev)); 711 if (rc) { 712 dev_err(&pdev->dev, "Error writing %x to remote spad %d\n", 713 ntb_max_mw(ndev), NUM_MWS); 714 goto out; 715 } 716 717 rc = ntb_write_remote_spad(ndev, NUM_QPS, nt->max_qps); 718 if (rc) { 719 dev_err(&pdev->dev, "Error writing %x to remote spad %d\n", 720 nt->max_qps, NUM_QPS); 721 goto out; 722 } 723 724 rc = ntb_write_remote_spad(ndev, VERSION, NTB_TRANSPORT_VERSION); 725 if (rc) { 726 dev_err(&pdev->dev, "Error writing %x to remote spad %d\n", 727 NTB_TRANSPORT_VERSION, VERSION); 728 goto out; 729 } 730 731 /* Query the remote side for its info */ 732 rc = ntb_read_remote_spad(ndev, VERSION, &val); 733 if (rc) { 734 dev_err(&pdev->dev, "Error reading remote spad %d\n", VERSION); 735 goto out; 736 } 737 738 if (val != NTB_TRANSPORT_VERSION) 739 goto out; 740 dev_dbg(&pdev->dev, "Remote version = %d\n", val); 741 742 rc = ntb_read_remote_spad(ndev, NUM_QPS, &val); 743 if (rc) { 744 dev_err(&pdev->dev, "Error reading remote spad %d\n", NUM_QPS); 745 goto out; 746 } 747 748 if (val != nt->max_qps) 749 goto out; 750 dev_dbg(&pdev->dev, "Remote max number of qps = %d\n", val); 751 752 rc = ntb_read_remote_spad(ndev, NUM_MWS, &val); 753 if (rc) { 754 dev_err(&pdev->dev, "Error reading remote spad %d\n", NUM_MWS); 755 goto out; 756 } 757 758 if (val != ntb_max_mw(ndev)) 759 goto out; 760 dev_dbg(&pdev->dev, "Remote number of mws = %d\n", val); 761 762 for (i = 0; i < ntb_max_mw(ndev); i++) { 763 u64 val64; 764 765 rc = ntb_read_remote_spad(ndev, MW0_SZ_HIGH + (i * 2), &val); 766 if (rc) { 767 dev_err(&pdev->dev, "Error reading remote spad %d\n", 768 MW0_SZ_HIGH + (i * 2)); 769 goto out1; 770 } 771 772 val64 = (u64) val << 32; 773 774 rc = ntb_read_remote_spad(ndev, MW0_SZ_LOW + (i * 2), &val); 775 if (rc) { 776 dev_err(&pdev->dev, "Error reading remote spad %d\n", 777 MW0_SZ_LOW + (i * 2)); 778 goto out1; 779 } 780 781 val64 |= val; 782 783 dev_dbg(&pdev->dev, "Remote MW%d size = %llu\n", i, val64); 784 785 rc = ntb_set_mw(nt, i, val64); 786 if (rc) 787 goto out1; 788 } 789 790 nt->transport_link = NTB_LINK_UP; 791 792 for (i = 0; i < nt->max_qps; i++) { 793 struct ntb_transport_qp *qp = &nt->qps[i]; 794 795 ntb_transport_setup_qp_mw(nt, i); 796 797 if (qp->client_ready == NTB_LINK_UP) 798 schedule_delayed_work(&qp->link_work, 0); 799 } 800 801 return; 802 803out1: 804 for (i = 0; i < ntb_max_mw(ndev); i++) 805 ntb_free_mw(nt, i); 806out: 807 if (ntb_hw_link_status(ndev)) 808 schedule_delayed_work(&nt->link_work, 809 msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT)); 810} 811 812static void ntb_qp_link_work(struct work_struct *work) 813{ 814 struct ntb_transport_qp *qp = container_of(work, 815 struct ntb_transport_qp, 816 link_work.work); 817 struct pci_dev *pdev = ntb_query_pdev(qp->ndev); 818 struct ntb_transport *nt = qp->transport; 819 int rc, val; 820 821 WARN_ON(nt->transport_link != NTB_LINK_UP); 822 823 rc = ntb_read_local_spad(nt->ndev, QP_LINKS, &val); 824 if (rc) { 825 dev_err(&pdev->dev, "Error reading spad %d\n", QP_LINKS); 826 return; 827 } 828 829 rc = ntb_write_remote_spad(nt->ndev, QP_LINKS, val | 1 << qp->qp_num); 830 if (rc) 831 dev_err(&pdev->dev, "Error writing %x to remote spad %d\n", 832 val | 1 << qp->qp_num, QP_LINKS); 833 834 /* query remote spad for qp ready bits */ 835 rc = ntb_read_remote_spad(nt->ndev, QP_LINKS, &val); 836 if (rc) 837 dev_err(&pdev->dev, "Error reading remote spad %d\n", QP_LINKS); 838 839 dev_dbg(&pdev->dev, "Remote QP link status = %x\n", val); 840 841 /* See if the remote side is up */ 842 if (1 << qp->qp_num & val) { 843 qp->qp_link = NTB_LINK_UP; 844 845 dev_info(&pdev->dev, "qp %d: Link Up\n", qp->qp_num); 846 if (qp->event_handler) 847 qp->event_handler(qp->cb_data, NTB_LINK_UP); 848 } else if (nt->transport_link == NTB_LINK_UP) 849 schedule_delayed_work(&qp->link_work, 850 msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT)); 851} 852 853static int ntb_transport_init_queue(struct ntb_transport *nt, 854 unsigned int qp_num) 855{ 856 struct ntb_transport_qp *qp; 857 unsigned int num_qps_mw, tx_size; 858 u8 mw_num, mw_max; 859 u64 qp_offset; 860 861 mw_max = ntb_max_mw(nt->ndev); 862 mw_num = QP_TO_MW(nt->ndev, qp_num); 863 864 qp = &nt->qps[qp_num]; 865 qp->qp_num = qp_num; 866 qp->transport = nt; 867 qp->ndev = nt->ndev; 868 qp->qp_link = NTB_LINK_DOWN; 869 qp->client_ready = NTB_LINK_DOWN; 870 qp->event_handler = NULL; 871 872 if (nt->max_qps % mw_max && mw_num + 1 < nt->max_qps / mw_max) 873 num_qps_mw = nt->max_qps / mw_max + 1; 874 else 875 num_qps_mw = nt->max_qps / mw_max; 876 877 tx_size = (unsigned int) ntb_get_mw_size(qp->ndev, mw_num) / num_qps_mw; 878 qp_offset = qp_num / mw_max * tx_size; 879 qp->tx_mw = ntb_get_mw_vbase(nt->ndev, mw_num) + qp_offset; 880 if (!qp->tx_mw) 881 return -EINVAL; 882 883 qp->tx_mw_phys = ntb_get_mw_base(qp->ndev, mw_num) + qp_offset; 884 if (!qp->tx_mw_phys) 885 return -EINVAL; 886 887 tx_size -= sizeof(struct ntb_rx_info); 888 qp->rx_info = qp->tx_mw + tx_size; 889 890 /* Due to housekeeping, there must be atleast 2 buffs */ 891 qp->tx_max_frame = min(transport_mtu, tx_size / 2); 892 qp->tx_max_entry = tx_size / qp->tx_max_frame; 893 894 if (ntb_query_debugfs(nt->ndev)) { 895 char debugfs_name[4]; 896 897 snprintf(debugfs_name, 4, "qp%d", qp_num); 898 qp->debugfs_dir = debugfs_create_dir(debugfs_name, 899 ntb_query_debugfs(nt->ndev)); 900 901 qp->debugfs_stats = debugfs_create_file("stats", S_IRUSR, 902 qp->debugfs_dir, qp, 903 &ntb_qp_debugfs_stats); 904 } 905 906 INIT_DELAYED_WORK(&qp->link_work, ntb_qp_link_work); 907 INIT_WORK(&qp->link_cleanup, ntb_qp_link_cleanup_work); 908 909 spin_lock_init(&qp->ntb_rx_pend_q_lock); 910 spin_lock_init(&qp->ntb_rx_free_q_lock); 911 spin_lock_init(&qp->ntb_tx_free_q_lock); 912 913 INIT_LIST_HEAD(&qp->rx_pend_q); 914 INIT_LIST_HEAD(&qp->rx_free_q); 915 INIT_LIST_HEAD(&qp->tx_free_q); 916 917 return 0; 918} 919 920int ntb_transport_init(struct pci_dev *pdev) 921{ 922 struct ntb_transport *nt; 923 int rc, i; 924 925 nt = kzalloc(sizeof(struct ntb_transport), GFP_KERNEL); 926 if (!nt) 927 return -ENOMEM; 928 929 nt->ndev = ntb_register_transport(pdev, nt); 930 if (!nt->ndev) { 931 rc = -EIO; 932 goto err; 933 } 934 935 nt->mw = kcalloc(ntb_max_mw(nt->ndev), sizeof(struct ntb_transport_mw), 936 GFP_KERNEL); 937 if (!nt->mw) { 938 rc = -ENOMEM; 939 goto err1; 940 } 941 942 if (max_num_clients) 943 nt->max_qps = min(ntb_max_cbs(nt->ndev), max_num_clients); 944 else 945 nt->max_qps = min(ntb_max_cbs(nt->ndev), ntb_max_mw(nt->ndev)); 946 947 nt->qps = kcalloc(nt->max_qps, sizeof(struct ntb_transport_qp), 948 GFP_KERNEL); 949 if (!nt->qps) { 950 rc = -ENOMEM; 951 goto err2; 952 } 953 954 nt->qp_bitmap = ((u64) 1 << nt->max_qps) - 1; 955 956 for (i = 0; i < nt->max_qps; i++) { 957 rc = ntb_transport_init_queue(nt, i); 958 if (rc) 959 goto err3; 960 } 961 962 INIT_DELAYED_WORK(&nt->link_work, ntb_transport_link_work); 963 INIT_WORK(&nt->link_cleanup, ntb_transport_link_cleanup_work); 964 965 rc = ntb_register_event_callback(nt->ndev, 966 ntb_transport_event_callback); 967 if (rc) 968 goto err3; 969 970 INIT_LIST_HEAD(&nt->client_devs); 971 rc = ntb_bus_init(nt); 972 if (rc) 973 goto err4; 974 975 if (ntb_hw_link_status(nt->ndev)) 976 schedule_delayed_work(&nt->link_work, 0); 977 978 return 0; 979 980err4: 981 ntb_unregister_event_callback(nt->ndev); 982err3: 983 kfree(nt->qps); 984err2: 985 kfree(nt->mw); 986err1: 987 ntb_unregister_transport(nt->ndev); 988err: 989 kfree(nt); 990 return rc; 991} 992 993void ntb_transport_free(void *transport) 994{ 995 struct ntb_transport *nt = transport; 996 struct ntb_device *ndev = nt->ndev; 997 int i; 998 999 ntb_transport_link_cleanup(nt); 1000 1001 /* verify that all the qp's are freed */ 1002 for (i = 0; i < nt->max_qps; i++) { 1003 if (!test_bit(i, &nt->qp_bitmap)) 1004 ntb_transport_free_queue(&nt->qps[i]); 1005 debugfs_remove_recursive(nt->qps[i].debugfs_dir); 1006 } 1007 1008 ntb_bus_remove(nt); 1009 1010 cancel_delayed_work_sync(&nt->link_work); 1011 1012 ntb_unregister_event_callback(ndev); 1013 1014 for (i = 0; i < ntb_max_mw(ndev); i++) 1015 ntb_free_mw(nt, i); 1016 1017 kfree(nt->qps); 1018 kfree(nt->mw); 1019 ntb_unregister_transport(ndev); 1020 kfree(nt); 1021} 1022 1023static void ntb_rx_copy_callback(void *data) 1024{ 1025 struct ntb_queue_entry *entry = data; 1026 struct ntb_transport_qp *qp = entry->qp; 1027 void *cb_data = entry->cb_data; 1028 unsigned int len = entry->len; 1029 struct ntb_payload_header *hdr = entry->rx_hdr; 1030 1031 /* Ensure that the data is fully copied out before clearing the flag */ 1032 wmb(); 1033 hdr->flags = 0; 1034 1035 iowrite32(entry->index, &qp->rx_info->entry); 1036 1037 ntb_list_add(&qp->ntb_rx_free_q_lock, &entry->entry, &qp->rx_free_q); 1038 1039 if (qp->rx_handler && qp->client_ready == NTB_LINK_UP) 1040 qp->rx_handler(qp, qp->cb_data, cb_data, len); 1041} 1042 1043static void ntb_memcpy_rx(struct ntb_queue_entry *entry, void *offset) 1044{ 1045 void *buf = entry->buf; 1046 size_t len = entry->len; 1047 1048 memcpy(buf, offset, len); 1049 1050 ntb_rx_copy_callback(entry); 1051} 1052 1053static void ntb_async_rx(struct ntb_queue_entry *entry, void *offset, 1054 size_t len) 1055{ 1056 struct dma_async_tx_descriptor *txd; 1057 struct ntb_transport_qp *qp = entry->qp; 1058 struct dma_chan *chan = qp->dma_chan; 1059 struct dma_device *device; 1060 size_t pay_off, buff_off; 1061 struct dmaengine_unmap_data *unmap; 1062 dma_cookie_t cookie; 1063 void *buf = entry->buf; 1064 1065 entry->len = len; 1066 1067 if (!chan) 1068 goto err; 1069 1070 if (len < copy_bytes) 1071 goto err_wait; 1072 1073 device = chan->device; 1074 pay_off = (size_t) offset & ~PAGE_MASK; 1075 buff_off = (size_t) buf & ~PAGE_MASK; 1076 1077 if (!is_dma_copy_aligned(device, pay_off, buff_off, len)) 1078 goto err_wait; 1079 1080 unmap = dmaengine_get_unmap_data(device->dev, 2, GFP_NOWAIT); 1081 if (!unmap) 1082 goto err_wait; 1083 1084 unmap->len = len; 1085 unmap->addr[0] = dma_map_page(device->dev, virt_to_page(offset), 1086 pay_off, len, DMA_TO_DEVICE); 1087 if (dma_mapping_error(device->dev, unmap->addr[0])) 1088 goto err_get_unmap; 1089 1090 unmap->to_cnt = 1; 1091 1092 unmap->addr[1] = dma_map_page(device->dev, virt_to_page(buf), 1093 buff_off, len, DMA_FROM_DEVICE); 1094 if (dma_mapping_error(device->dev, unmap->addr[1])) 1095 goto err_get_unmap; 1096 1097 unmap->from_cnt = 1; 1098 1099 txd = device->device_prep_dma_memcpy(chan, unmap->addr[1], 1100 unmap->addr[0], len, 1101 DMA_PREP_INTERRUPT); 1102 if (!txd) 1103 goto err_get_unmap; 1104 1105 txd->callback = ntb_rx_copy_callback; 1106 txd->callback_param = entry; 1107 dma_set_unmap(txd, unmap); 1108 1109 cookie = dmaengine_submit(txd); 1110 if (dma_submit_error(cookie)) 1111 goto err_set_unmap; 1112 1113 dmaengine_unmap_put(unmap); 1114 1115 qp->last_cookie = cookie; 1116 1117 qp->rx_async++; 1118 1119 return; 1120 1121err_set_unmap: 1122 dmaengine_unmap_put(unmap); 1123err_get_unmap: 1124 dmaengine_unmap_put(unmap); 1125err_wait: 1126 /* If the callbacks come out of order, the writing of the index to the 1127 * last completed will be out of order. This may result in the 1128 * receive stalling forever. 1129 */ 1130 dma_sync_wait(chan, qp->last_cookie); 1131err: 1132 ntb_memcpy_rx(entry, offset); 1133 qp->rx_memcpy++; 1134} 1135 1136static int ntb_process_rxc(struct ntb_transport_qp *qp) 1137{ 1138 struct ntb_payload_header *hdr; 1139 struct ntb_queue_entry *entry; 1140 void *offset; 1141 1142 offset = qp->rx_buff + qp->rx_max_frame * qp->rx_index; 1143 hdr = offset + qp->rx_max_frame - sizeof(struct ntb_payload_header); 1144 1145 entry = ntb_list_rm(&qp->ntb_rx_pend_q_lock, &qp->rx_pend_q); 1146 if (!entry) { 1147 dev_dbg(&ntb_query_pdev(qp->ndev)->dev, 1148 "no buffer - HDR ver %u, len %d, flags %x\n", 1149 hdr->ver, hdr->len, hdr->flags); 1150 qp->rx_err_no_buf++; 1151 return -ENOMEM; 1152 } 1153 1154 if (!(hdr->flags & DESC_DONE_FLAG)) { 1155 ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, 1156 &qp->rx_pend_q); 1157 qp->rx_ring_empty++; 1158 return -EAGAIN; 1159 } 1160 1161 if (hdr->ver != (u32) qp->rx_pkts) { 1162 dev_dbg(&ntb_query_pdev(qp->ndev)->dev, 1163 "qp %d: version mismatch, expected %llu - got %u\n", 1164 qp->qp_num, qp->rx_pkts, hdr->ver); 1165 ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, 1166 &qp->rx_pend_q); 1167 qp->rx_err_ver++; 1168 return -EIO; 1169 } 1170 1171 if (hdr->flags & LINK_DOWN_FLAG) { 1172 ntb_qp_link_down(qp); 1173 1174 goto err; 1175 } 1176 1177 dev_dbg(&ntb_query_pdev(qp->ndev)->dev, 1178 "rx offset %u, ver %u - %d payload received, buf size %d\n", 1179 qp->rx_index, hdr->ver, hdr->len, entry->len); 1180 1181 qp->rx_bytes += hdr->len; 1182 qp->rx_pkts++; 1183 1184 if (hdr->len > entry->len) { 1185 qp->rx_err_oflow++; 1186 dev_dbg(&ntb_query_pdev(qp->ndev)->dev, 1187 "RX overflow! Wanted %d got %d\n", 1188 hdr->len, entry->len); 1189 1190 goto err; 1191 } 1192 1193 entry->index = qp->rx_index; 1194 entry->rx_hdr = hdr; 1195 1196 ntb_async_rx(entry, offset, hdr->len); 1197 1198out: 1199 qp->rx_index++; 1200 qp->rx_index %= qp->rx_max_entry; 1201 1202 return 0; 1203 1204err: 1205 ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, &qp->rx_pend_q); 1206 /* Ensure that the data is fully copied out before clearing the flag */ 1207 wmb(); 1208 hdr->flags = 0; 1209 iowrite32(qp->rx_index, &qp->rx_info->entry); 1210 1211 goto out; 1212} 1213 1214static int ntb_transport_rxc_db(void *data, int db_num) 1215{ 1216 struct ntb_transport_qp *qp = data; 1217 int rc, i; 1218 1219 dev_dbg(&ntb_query_pdev(qp->ndev)->dev, "%s: doorbell %d received\n", 1220 __func__, db_num); 1221 1222 /* Limit the number of packets processed in a single interrupt to 1223 * provide fairness to others 1224 */ 1225 for (i = 0; i < qp->rx_max_entry; i++) { 1226 rc = ntb_process_rxc(qp); 1227 if (rc) 1228 break; 1229 } 1230 1231 if (qp->dma_chan) 1232 dma_async_issue_pending(qp->dma_chan); 1233 1234 return i; 1235} 1236 1237static void ntb_tx_copy_callback(void *data) 1238{ 1239 struct ntb_queue_entry *entry = data; 1240 struct ntb_transport_qp *qp = entry->qp; 1241 struct ntb_payload_header __iomem *hdr = entry->tx_hdr; 1242 1243 /* Ensure that the data is fully copied out before setting the flags */ 1244 wmb(); 1245 iowrite32(entry->flags | DESC_DONE_FLAG, &hdr->flags); 1246 1247 ntb_ring_doorbell(qp->ndev, qp->qp_num); 1248 1249 /* The entry length can only be zero if the packet is intended to be a 1250 * "link down" or similar. Since no payload is being sent in these 1251 * cases, there is nothing to add to the completion queue. 1252 */ 1253 if (entry->len > 0) { 1254 qp->tx_bytes += entry->len; 1255 1256 if (qp->tx_handler) 1257 qp->tx_handler(qp, qp->cb_data, entry->cb_data, 1258 entry->len); 1259 } 1260 1261 ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, &qp->tx_free_q); 1262} 1263 1264static void ntb_memcpy_tx(struct ntb_queue_entry *entry, void __iomem *offset) 1265{ 1266 memcpy_toio(offset, entry->buf, entry->len); 1267 1268 ntb_tx_copy_callback(entry); 1269} 1270 1271static void ntb_async_tx(struct ntb_transport_qp *qp, 1272 struct ntb_queue_entry *entry) 1273{ 1274 struct ntb_payload_header __iomem *hdr; 1275 struct dma_async_tx_descriptor *txd; 1276 struct dma_chan *chan = qp->dma_chan; 1277 struct dma_device *device; 1278 size_t dest_off, buff_off; 1279 struct dmaengine_unmap_data *unmap; 1280 dma_addr_t dest; 1281 dma_cookie_t cookie; 1282 void __iomem *offset; 1283 size_t len = entry->len; 1284 void *buf = entry->buf; 1285 1286 offset = qp->tx_mw + qp->tx_max_frame * qp->tx_index; 1287 hdr = offset + qp->tx_max_frame - sizeof(struct ntb_payload_header); 1288 entry->tx_hdr = hdr; 1289 1290 iowrite32(entry->len, &hdr->len); 1291 iowrite32((u32) qp->tx_pkts, &hdr->ver); 1292 1293 if (!chan) 1294 goto err; 1295 1296 if (len < copy_bytes) 1297 goto err; 1298 1299 device = chan->device; 1300 dest = qp->tx_mw_phys + qp->tx_max_frame * qp->tx_index; 1301 buff_off = (size_t) buf & ~PAGE_MASK; 1302 dest_off = (size_t) dest & ~PAGE_MASK; 1303 1304 if (!is_dma_copy_aligned(device, buff_off, dest_off, len)) 1305 goto err; 1306 1307 unmap = dmaengine_get_unmap_data(device->dev, 1, GFP_NOWAIT); 1308 if (!unmap) 1309 goto err; 1310 1311 unmap->len = len; 1312 unmap->addr[0] = dma_map_page(device->dev, virt_to_page(buf), 1313 buff_off, len, DMA_TO_DEVICE); 1314 if (dma_mapping_error(device->dev, unmap->addr[0])) 1315 goto err_get_unmap; 1316 1317 unmap->to_cnt = 1; 1318 1319 txd = device->device_prep_dma_memcpy(chan, dest, unmap->addr[0], len, 1320 DMA_PREP_INTERRUPT); 1321 if (!txd) 1322 goto err_get_unmap; 1323 1324 txd->callback = ntb_tx_copy_callback; 1325 txd->callback_param = entry; 1326 dma_set_unmap(txd, unmap); 1327 1328 cookie = dmaengine_submit(txd); 1329 if (dma_submit_error(cookie)) 1330 goto err_set_unmap; 1331 1332 dmaengine_unmap_put(unmap); 1333 1334 dma_async_issue_pending(chan); 1335 qp->tx_async++; 1336 1337 return; 1338err_set_unmap: 1339 dmaengine_unmap_put(unmap); 1340err_get_unmap: 1341 dmaengine_unmap_put(unmap); 1342err: 1343 ntb_memcpy_tx(entry, offset); 1344 qp->tx_memcpy++; 1345} 1346 1347static int ntb_process_tx(struct ntb_transport_qp *qp, 1348 struct ntb_queue_entry *entry) 1349{ 1350 dev_dbg(&ntb_query_pdev(qp->ndev)->dev, "%lld - tx %u, entry len %d flags %x buff %p\n", 1351 qp->tx_pkts, qp->tx_index, entry->len, entry->flags, 1352 entry->buf); 1353 if (qp->tx_index == qp->remote_rx_info->entry) { 1354 qp->tx_ring_full++; 1355 return -EAGAIN; 1356 } 1357 1358 if (entry->len > qp->tx_max_frame - sizeof(struct ntb_payload_header)) { 1359 if (qp->tx_handler) 1360 qp->tx_handler(qp->cb_data, qp, NULL, -EIO); 1361 1362 ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, 1363 &qp->tx_free_q); 1364 return 0; 1365 } 1366 1367 ntb_async_tx(qp, entry); 1368 1369 qp->tx_index++; 1370 qp->tx_index %= qp->tx_max_entry; 1371 1372 qp->tx_pkts++; 1373 1374 return 0; 1375} 1376 1377static void ntb_send_link_down(struct ntb_transport_qp *qp) 1378{ 1379 struct pci_dev *pdev = ntb_query_pdev(qp->ndev); 1380 struct ntb_queue_entry *entry; 1381 int i, rc; 1382 1383 if (qp->qp_link == NTB_LINK_DOWN) 1384 return; 1385 1386 qp->qp_link = NTB_LINK_DOWN; 1387 dev_info(&pdev->dev, "qp %d: Link Down\n", qp->qp_num); 1388 1389 for (i = 0; i < NTB_LINK_DOWN_TIMEOUT; i++) { 1390 entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q); 1391 if (entry) 1392 break; 1393 msleep(100); 1394 } 1395 1396 if (!entry) 1397 return; 1398 1399 entry->cb_data = NULL; 1400 entry->buf = NULL; 1401 entry->len = 0; 1402 entry->flags = LINK_DOWN_FLAG; 1403 1404 rc = ntb_process_tx(qp, entry); 1405 if (rc) 1406 dev_err(&pdev->dev, "ntb: QP%d unable to send linkdown msg\n", 1407 qp->qp_num); 1408} 1409 1410/** 1411 * ntb_transport_create_queue - Create a new NTB transport layer queue 1412 * @rx_handler: receive callback function 1413 * @tx_handler: transmit callback function 1414 * @event_handler: event callback function 1415 * 1416 * Create a new NTB transport layer queue and provide the queue with a callback 1417 * routine for both transmit and receive. The receive callback routine will be 1418 * used to pass up data when the transport has received it on the queue. The 1419 * transmit callback routine will be called when the transport has completed the 1420 * transmission of the data on the queue and the data is ready to be freed. 1421 * 1422 * RETURNS: pointer to newly created ntb_queue, NULL on error. 1423 */ 1424struct ntb_transport_qp * 1425ntb_transport_create_queue(void *data, struct pci_dev *pdev, 1426 const struct ntb_queue_handlers *handlers) 1427{ 1428 struct ntb_queue_entry *entry; 1429 struct ntb_transport_qp *qp; 1430 struct ntb_transport *nt; 1431 unsigned int free_queue; 1432 int rc, i; 1433 1434 nt = ntb_find_transport(pdev); 1435 if (!nt) 1436 goto err; 1437 1438 free_queue = ffs(nt->qp_bitmap); 1439 if (!free_queue) 1440 goto err; 1441 1442 /* decrement free_queue to make it zero based */ 1443 free_queue--; 1444 1445 clear_bit(free_queue, &nt->qp_bitmap); 1446 1447 qp = &nt->qps[free_queue]; 1448 qp->cb_data = data; 1449 qp->rx_handler = handlers->rx_handler; 1450 qp->tx_handler = handlers->tx_handler; 1451 qp->event_handler = handlers->event_handler; 1452 1453 dmaengine_get(); 1454 qp->dma_chan = dma_find_channel(DMA_MEMCPY); 1455 if (!qp->dma_chan) { 1456 dmaengine_put(); 1457 dev_info(&pdev->dev, "Unable to allocate DMA channel, using CPU instead\n"); 1458 } 1459 1460 for (i = 0; i < NTB_QP_DEF_NUM_ENTRIES; i++) { 1461 entry = kzalloc(sizeof(struct ntb_queue_entry), GFP_ATOMIC); 1462 if (!entry) 1463 goto err1; 1464 1465 entry->qp = qp; 1466 ntb_list_add(&qp->ntb_rx_free_q_lock, &entry->entry, 1467 &qp->rx_free_q); 1468 } 1469 1470 for (i = 0; i < NTB_QP_DEF_NUM_ENTRIES; i++) { 1471 entry = kzalloc(sizeof(struct ntb_queue_entry), GFP_ATOMIC); 1472 if (!entry) 1473 goto err2; 1474 1475 entry->qp = qp; 1476 ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, 1477 &qp->tx_free_q); 1478 } 1479 1480 rc = ntb_register_db_callback(qp->ndev, free_queue, qp, 1481 ntb_transport_rxc_db); 1482 if (rc) 1483 goto err2; 1484 1485 dev_info(&pdev->dev, "NTB Transport QP %d created\n", qp->qp_num); 1486 1487 return qp; 1488 1489err2: 1490 while ((entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q))) 1491 kfree(entry); 1492err1: 1493 while ((entry = ntb_list_rm(&qp->ntb_rx_free_q_lock, &qp->rx_free_q))) 1494 kfree(entry); 1495 if (qp->dma_chan) 1496 dmaengine_put(); 1497 set_bit(free_queue, &nt->qp_bitmap); 1498err: 1499 return NULL; 1500} 1501EXPORT_SYMBOL_GPL(ntb_transport_create_queue); 1502 1503/** 1504 * ntb_transport_free_queue - Frees NTB transport queue 1505 * @qp: NTB queue to be freed 1506 * 1507 * Frees NTB transport queue 1508 */ 1509void ntb_transport_free_queue(struct ntb_transport_qp *qp) 1510{ 1511 struct pci_dev *pdev; 1512 struct ntb_queue_entry *entry; 1513 1514 if (!qp) 1515 return; 1516 1517 pdev = ntb_query_pdev(qp->ndev); 1518 1519 if (qp->dma_chan) { 1520 struct dma_chan *chan = qp->dma_chan; 1521 /* Putting the dma_chan to NULL will force any new traffic to be 1522 * processed by the CPU instead of the DAM engine 1523 */ 1524 qp->dma_chan = NULL; 1525 1526 /* Try to be nice and wait for any queued DMA engine 1527 * transactions to process before smashing it with a rock 1528 */ 1529 dma_sync_wait(chan, qp->last_cookie); 1530 dmaengine_terminate_all(chan); 1531 dmaengine_put(); 1532 } 1533 1534 ntb_unregister_db_callback(qp->ndev, qp->qp_num); 1535 1536 cancel_delayed_work_sync(&qp->link_work); 1537 1538 while ((entry = ntb_list_rm(&qp->ntb_rx_free_q_lock, &qp->rx_free_q))) 1539 kfree(entry); 1540 1541 while ((entry = ntb_list_rm(&qp->ntb_rx_pend_q_lock, &qp->rx_pend_q))) { 1542 dev_warn(&pdev->dev, "Freeing item from a non-empty queue\n"); 1543 kfree(entry); 1544 } 1545 1546 while ((entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q))) 1547 kfree(entry); 1548 1549 set_bit(qp->qp_num, &qp->transport->qp_bitmap); 1550 1551 dev_info(&pdev->dev, "NTB Transport QP %d freed\n", qp->qp_num); 1552} 1553EXPORT_SYMBOL_GPL(ntb_transport_free_queue); 1554 1555/** 1556 * ntb_transport_rx_remove - Dequeues enqueued rx packet 1557 * @qp: NTB queue to be freed 1558 * @len: pointer to variable to write enqueued buffers length 1559 * 1560 * Dequeues unused buffers from receive queue. Should only be used during 1561 * shutdown of qp. 1562 * 1563 * RETURNS: NULL error value on error, or void* for success. 1564 */ 1565void *ntb_transport_rx_remove(struct ntb_transport_qp *qp, unsigned int *len) 1566{ 1567 struct ntb_queue_entry *entry; 1568 void *buf; 1569 1570 if (!qp || qp->client_ready == NTB_LINK_UP) 1571 return NULL; 1572 1573 entry = ntb_list_rm(&qp->ntb_rx_pend_q_lock, &qp->rx_pend_q); 1574 if (!entry) 1575 return NULL; 1576 1577 buf = entry->cb_data; 1578 *len = entry->len; 1579 1580 ntb_list_add(&qp->ntb_rx_free_q_lock, &entry->entry, &qp->rx_free_q); 1581 1582 return buf; 1583} 1584EXPORT_SYMBOL_GPL(ntb_transport_rx_remove); 1585 1586/** 1587 * ntb_transport_rx_enqueue - Enqueue a new NTB queue entry 1588 * @qp: NTB transport layer queue the entry is to be enqueued on 1589 * @cb: per buffer pointer for callback function to use 1590 * @data: pointer to data buffer that incoming packets will be copied into 1591 * @len: length of the data buffer 1592 * 1593 * Enqueue a new receive buffer onto the transport queue into which a NTB 1594 * payload can be received into. 1595 * 1596 * RETURNS: An appropriate -ERRNO error value on error, or zero for success. 1597 */ 1598int ntb_transport_rx_enqueue(struct ntb_transport_qp *qp, void *cb, void *data, 1599 unsigned int len) 1600{ 1601 struct ntb_queue_entry *entry; 1602 1603 if (!qp) 1604 return -EINVAL; 1605 1606 entry = ntb_list_rm(&qp->ntb_rx_free_q_lock, &qp->rx_free_q); 1607 if (!entry) 1608 return -ENOMEM; 1609 1610 entry->cb_data = cb; 1611 entry->buf = data; 1612 entry->len = len; 1613 1614 ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, &qp->rx_pend_q); 1615 1616 return 0; 1617} 1618EXPORT_SYMBOL_GPL(ntb_transport_rx_enqueue); 1619 1620/** 1621 * ntb_transport_tx_enqueue - Enqueue a new NTB queue entry 1622 * @qp: NTB transport layer queue the entry is to be enqueued on 1623 * @cb: per buffer pointer for callback function to use 1624 * @data: pointer to data buffer that will be sent 1625 * @len: length of the data buffer 1626 * 1627 * Enqueue a new transmit buffer onto the transport queue from which a NTB 1628 * payload will be transmitted. This assumes that a lock is being held to 1629 * serialize access to the qp. 1630 * 1631 * RETURNS: An appropriate -ERRNO error value on error, or zero for success. 1632 */ 1633int ntb_transport_tx_enqueue(struct ntb_transport_qp *qp, void *cb, void *data, 1634 unsigned int len) 1635{ 1636 struct ntb_queue_entry *entry; 1637 int rc; 1638 1639 if (!qp || qp->qp_link != NTB_LINK_UP || !len) 1640 return -EINVAL; 1641 1642 entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q); 1643 if (!entry) { 1644 qp->tx_err_no_buf++; 1645 return -ENOMEM; 1646 } 1647 1648 entry->cb_data = cb; 1649 entry->buf = data; 1650 entry->len = len; 1651 entry->flags = 0; 1652 1653 rc = ntb_process_tx(qp, entry); 1654 if (rc) 1655 ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, 1656 &qp->tx_free_q); 1657 1658 return rc; 1659} 1660EXPORT_SYMBOL_GPL(ntb_transport_tx_enqueue); 1661 1662/** 1663 * ntb_transport_link_up - Notify NTB transport of client readiness to use queue 1664 * @qp: NTB transport layer queue to be enabled 1665 * 1666 * Notify NTB transport layer of client readiness to use queue 1667 */ 1668void ntb_transport_link_up(struct ntb_transport_qp *qp) 1669{ 1670 if (!qp) 1671 return; 1672 1673 qp->client_ready = NTB_LINK_UP; 1674 1675 if (qp->transport->transport_link == NTB_LINK_UP) 1676 schedule_delayed_work(&qp->link_work, 0); 1677} 1678EXPORT_SYMBOL_GPL(ntb_transport_link_up); 1679 1680/** 1681 * ntb_transport_link_down - Notify NTB transport to no longer enqueue data 1682 * @qp: NTB transport layer queue to be disabled 1683 * 1684 * Notify NTB transport layer of client's desire to no longer receive data on 1685 * transport queue specified. It is the client's responsibility to ensure all 1686 * entries on queue are purged or otherwise handled appropriately. 1687 */ 1688void ntb_transport_link_down(struct ntb_transport_qp *qp) 1689{ 1690 struct pci_dev *pdev; 1691 int rc, val; 1692 1693 if (!qp) 1694 return; 1695 1696 pdev = ntb_query_pdev(qp->ndev); 1697 qp->client_ready = NTB_LINK_DOWN; 1698 1699 rc = ntb_read_local_spad(qp->ndev, QP_LINKS, &val); 1700 if (rc) { 1701 dev_err(&pdev->dev, "Error reading spad %d\n", QP_LINKS); 1702 return; 1703 } 1704 1705 rc = ntb_write_remote_spad(qp->ndev, QP_LINKS, 1706 val & ~(1 << qp->qp_num)); 1707 if (rc) 1708 dev_err(&pdev->dev, "Error writing %x to remote spad %d\n", 1709 val & ~(1 << qp->qp_num), QP_LINKS); 1710 1711 if (qp->qp_link == NTB_LINK_UP) 1712 ntb_send_link_down(qp); 1713 else 1714 cancel_delayed_work_sync(&qp->link_work); 1715} 1716EXPORT_SYMBOL_GPL(ntb_transport_link_down); 1717 1718/** 1719 * ntb_transport_link_query - Query transport link state 1720 * @qp: NTB transport layer queue to be queried 1721 * 1722 * Query connectivity to the remote system of the NTB transport queue 1723 * 1724 * RETURNS: true for link up or false for link down 1725 */ 1726bool ntb_transport_link_query(struct ntb_transport_qp *qp) 1727{ 1728 if (!qp) 1729 return false; 1730 1731 return qp->qp_link == NTB_LINK_UP; 1732} 1733EXPORT_SYMBOL_GPL(ntb_transport_link_query); 1734 1735/** 1736 * ntb_transport_qp_num - Query the qp number 1737 * @qp: NTB transport layer queue to be queried 1738 * 1739 * Query qp number of the NTB transport queue 1740 * 1741 * RETURNS: a zero based number specifying the qp number 1742 */ 1743unsigned char ntb_transport_qp_num(struct ntb_transport_qp *qp) 1744{ 1745 if (!qp) 1746 return 0; 1747 1748 return qp->qp_num; 1749} 1750EXPORT_SYMBOL_GPL(ntb_transport_qp_num); 1751 1752/** 1753 * ntb_transport_max_size - Query the max payload size of a qp 1754 * @qp: NTB transport layer queue to be queried 1755 * 1756 * Query the maximum payload size permissible on the given qp 1757 * 1758 * RETURNS: the max payload size of a qp 1759 */ 1760unsigned int ntb_transport_max_size(struct ntb_transport_qp *qp) 1761{ 1762 unsigned int max; 1763 1764 if (!qp) 1765 return 0; 1766 1767 if (!qp->dma_chan) 1768 return qp->tx_max_frame - sizeof(struct ntb_payload_header); 1769 1770 /* If DMA engine usage is possible, try to find the max size for that */ 1771 max = qp->tx_max_frame - sizeof(struct ntb_payload_header); 1772 max -= max % (1 << qp->dma_chan->device->copy_align); 1773 1774 return max; 1775} 1776EXPORT_SYMBOL_GPL(ntb_transport_max_size); 1777