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 63 static unsigned int transport_mtu = 0x401E; 64 module_param(transport_mtu, uint, 0644); 65 MODULE_PARM_DESC(transport_mtu, "Maximum size of NTB transport packets"); 66 67 static unsigned char max_num_clients; 68 module_param(max_num_clients, byte, 0644); 69 MODULE_PARM_DESC(max_num_clients, "Maximum number of NTB transport clients"); 70 71 static unsigned int copy_bytes = 1024; 72 module_param(copy_bytes, uint, 0644); 73 MODULE_PARM_DESC(copy_bytes, "Threshold under which NTB will use the CPU to copy instead of DMA"); 74 75 struct 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 92 struct ntb_rx_info { 93 unsigned int entry; 94 }; 95 96 struct 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 }; 154 155 struct ntb_transport_mw { 156 size_t size; 157 void *virt_addr; 158 dma_addr_t dma_addr; 159 }; 160 161 struct ntb_transport_client_dev { 162 struct list_head entry; 163 struct device dev; 164 }; 165 166 struct 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 }; 179 180 enum { 181 DESC_DONE_FLAG = 1 << 0, 182 LINK_DOWN_FLAG = 1 << 1, 183 }; 184 185 struct ntb_payload_header { 186 unsigned int ver; 187 unsigned int len; 188 unsigned int flags; 189 }; 190 191 enum { 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 10 206 207 static int ntb_match_bus(struct device *dev, struct device_driver *drv) 208 { 209 return !strncmp(dev_name(dev), drv->name, strlen(drv->name)); 210 } 211 212 static 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 } 227 228 static 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 } 241 242 static 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 }; 248 249 static LIST_HEAD(ntb_transport_list); 250 251 static 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 } 263 264 static 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 } 280 281 static 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 */ 295 void 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 } 308 EXPORT_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 */ 316 int 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; 354 355 err: 356 ntb_unregister_client_dev(device_name); 357 358 return rc; 359 } 360 EXPORT_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 */ 370 int 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 } 379 EXPORT_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 */ 389 void ntb_unregister_client(struct ntb_client *drv) 390 { 391 driver_unregister(&drv->driver); 392 } 393 EXPORT_SYMBOL_GPL(ntb_unregister_client); 394 395 static 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 } 464 465 static const struct file_operations ntb_qp_debugfs_stats = { 466 .owner = THIS_MODULE, 467 .open = simple_open, 468 .read = debugfs_read, 469 }; 470 471 static 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 } 480 481 static 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); 494 out: 495 spin_unlock_irqrestore(lock, flags); 496 497 return entry; 498 } 499 500 static 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 < 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 } 542 543 static 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 } 554 555 static 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 /* Notify HW the memory location of the receive buffer */ 580 ntb_set_mw_addr(nt->ndev, num_mw, mw->dma_addr); 581 582 return 0; 583 } 584 585 static void ntb_qp_link_cleanup(struct ntb_transport_qp *qp) 586 { 587 struct ntb_transport *nt = qp->transport; 588 struct pci_dev *pdev = ntb_query_pdev(nt->ndev); 589 590 if (qp->qp_link == NTB_LINK_DOWN) { 591 cancel_delayed_work_sync(&qp->link_work); 592 return; 593 } 594 595 if (qp->event_handler) 596 qp->event_handler(qp->cb_data, NTB_LINK_DOWN); 597 598 dev_info(&pdev->dev, "qp %d: Link Down\n", qp->qp_num); 599 qp->qp_link = NTB_LINK_DOWN; 600 } 601 602 static void ntb_qp_link_cleanup_work(struct work_struct *work) 603 { 604 struct ntb_transport_qp *qp = container_of(work, 605 struct ntb_transport_qp, 606 link_cleanup); 607 struct ntb_transport *nt = qp->transport; 608 609 ntb_qp_link_cleanup(qp); 610 611 if (nt->transport_link == NTB_LINK_UP) 612 schedule_delayed_work(&qp->link_work, 613 msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT)); 614 } 615 616 static void ntb_qp_link_down(struct ntb_transport_qp *qp) 617 { 618 schedule_work(&qp->link_cleanup); 619 } 620 621 static void ntb_transport_link_cleanup(struct ntb_transport *nt) 622 { 623 int i; 624 625 /* Pass along the info to any clients */ 626 for (i = 0; i < nt->max_qps; i++) 627 if (!test_bit(i, &nt->qp_bitmap)) 628 ntb_qp_link_cleanup(&nt->qps[i]); 629 630 if (nt->transport_link == NTB_LINK_DOWN) 631 cancel_delayed_work_sync(&nt->link_work); 632 else 633 nt->transport_link = NTB_LINK_DOWN; 634 635 /* The scratchpad registers keep the values if the remote side 636 * goes down, blast them now to give them a sane value the next 637 * time they are accessed 638 */ 639 for (i = 0; i < MAX_SPAD; i++) 640 ntb_write_local_spad(nt->ndev, i, 0); 641 } 642 643 static void ntb_transport_link_cleanup_work(struct work_struct *work) 644 { 645 struct ntb_transport *nt = container_of(work, struct ntb_transport, 646 link_cleanup); 647 648 ntb_transport_link_cleanup(nt); 649 } 650 651 static void ntb_transport_event_callback(void *data, enum ntb_hw_event event) 652 { 653 struct ntb_transport *nt = data; 654 655 switch (event) { 656 case NTB_EVENT_HW_LINK_UP: 657 schedule_delayed_work(&nt->link_work, 0); 658 break; 659 case NTB_EVENT_HW_LINK_DOWN: 660 schedule_work(&nt->link_cleanup); 661 break; 662 default: 663 BUG(); 664 } 665 } 666 667 static void ntb_transport_link_work(struct work_struct *work) 668 { 669 struct ntb_transport *nt = container_of(work, struct ntb_transport, 670 link_work.work); 671 struct ntb_device *ndev = nt->ndev; 672 struct pci_dev *pdev = ntb_query_pdev(ndev); 673 u32 val; 674 int rc, i; 675 676 /* send the local info, in the opposite order of the way we read it */ 677 for (i = 0; i < ntb_max_mw(ndev); i++) { 678 rc = ntb_write_remote_spad(ndev, MW0_SZ_HIGH + (i * 2), 679 ntb_get_mw_size(ndev, i) >> 32); 680 if (rc) { 681 dev_err(&pdev->dev, "Error writing %u to remote spad %d\n", 682 (u32)(ntb_get_mw_size(ndev, i) >> 32), 683 MW0_SZ_HIGH + (i * 2)); 684 goto out; 685 } 686 687 rc = ntb_write_remote_spad(ndev, MW0_SZ_LOW + (i * 2), 688 (u32) ntb_get_mw_size(ndev, i)); 689 if (rc) { 690 dev_err(&pdev->dev, "Error writing %u to remote spad %d\n", 691 (u32) ntb_get_mw_size(ndev, i), 692 MW0_SZ_LOW + (i * 2)); 693 goto out; 694 } 695 } 696 697 rc = ntb_write_remote_spad(ndev, NUM_MWS, ntb_max_mw(ndev)); 698 if (rc) { 699 dev_err(&pdev->dev, "Error writing %x to remote spad %d\n", 700 ntb_max_mw(ndev), NUM_MWS); 701 goto out; 702 } 703 704 rc = ntb_write_remote_spad(ndev, NUM_QPS, nt->max_qps); 705 if (rc) { 706 dev_err(&pdev->dev, "Error writing %x to remote spad %d\n", 707 nt->max_qps, NUM_QPS); 708 goto out; 709 } 710 711 rc = ntb_write_remote_spad(ndev, VERSION, NTB_TRANSPORT_VERSION); 712 if (rc) { 713 dev_err(&pdev->dev, "Error writing %x to remote spad %d\n", 714 NTB_TRANSPORT_VERSION, VERSION); 715 goto out; 716 } 717 718 /* Query the remote side for its info */ 719 rc = ntb_read_remote_spad(ndev, VERSION, &val); 720 if (rc) { 721 dev_err(&pdev->dev, "Error reading remote spad %d\n", VERSION); 722 goto out; 723 } 724 725 if (val != NTB_TRANSPORT_VERSION) 726 goto out; 727 dev_dbg(&pdev->dev, "Remote version = %d\n", val); 728 729 rc = ntb_read_remote_spad(ndev, NUM_QPS, &val); 730 if (rc) { 731 dev_err(&pdev->dev, "Error reading remote spad %d\n", NUM_QPS); 732 goto out; 733 } 734 735 if (val != nt->max_qps) 736 goto out; 737 dev_dbg(&pdev->dev, "Remote max number of qps = %d\n", val); 738 739 rc = ntb_read_remote_spad(ndev, NUM_MWS, &val); 740 if (rc) { 741 dev_err(&pdev->dev, "Error reading remote spad %d\n", NUM_MWS); 742 goto out; 743 } 744 745 if (val != ntb_max_mw(ndev)) 746 goto out; 747 dev_dbg(&pdev->dev, "Remote number of mws = %d\n", val); 748 749 for (i = 0; i < ntb_max_mw(ndev); i++) { 750 u64 val64; 751 752 rc = ntb_read_remote_spad(ndev, MW0_SZ_HIGH + (i * 2), &val); 753 if (rc) { 754 dev_err(&pdev->dev, "Error reading remote spad %d\n", 755 MW0_SZ_HIGH + (i * 2)); 756 goto out1; 757 } 758 759 val64 = (u64) val << 32; 760 761 rc = ntb_read_remote_spad(ndev, MW0_SZ_LOW + (i * 2), &val); 762 if (rc) { 763 dev_err(&pdev->dev, "Error reading remote spad %d\n", 764 MW0_SZ_LOW + (i * 2)); 765 goto out1; 766 } 767 768 val64 |= val; 769 770 dev_dbg(&pdev->dev, "Remote MW%d size = %llu\n", i, val64); 771 772 rc = ntb_set_mw(nt, i, val64); 773 if (rc) 774 goto out1; 775 } 776 777 nt->transport_link = NTB_LINK_UP; 778 779 for (i = 0; i < nt->max_qps; i++) { 780 struct ntb_transport_qp *qp = &nt->qps[i]; 781 782 ntb_transport_setup_qp_mw(nt, i); 783 784 if (qp->client_ready == NTB_LINK_UP) 785 schedule_delayed_work(&qp->link_work, 0); 786 } 787 788 return; 789 790 out1: 791 for (i = 0; i < ntb_max_mw(ndev); i++) 792 ntb_free_mw(nt, i); 793 out: 794 if (ntb_hw_link_status(ndev)) 795 schedule_delayed_work(&nt->link_work, 796 msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT)); 797 } 798 799 static void ntb_qp_link_work(struct work_struct *work) 800 { 801 struct ntb_transport_qp *qp = container_of(work, 802 struct ntb_transport_qp, 803 link_work.work); 804 struct pci_dev *pdev = ntb_query_pdev(qp->ndev); 805 struct ntb_transport *nt = qp->transport; 806 int rc, val; 807 808 WARN_ON(nt->transport_link != NTB_LINK_UP); 809 810 rc = ntb_read_local_spad(nt->ndev, QP_LINKS, &val); 811 if (rc) { 812 dev_err(&pdev->dev, "Error reading spad %d\n", QP_LINKS); 813 return; 814 } 815 816 rc = ntb_write_remote_spad(nt->ndev, QP_LINKS, val | 1 << qp->qp_num); 817 if (rc) 818 dev_err(&pdev->dev, "Error writing %x to remote spad %d\n", 819 val | 1 << qp->qp_num, QP_LINKS); 820 821 /* query remote spad for qp ready bits */ 822 rc = ntb_read_remote_spad(nt->ndev, QP_LINKS, &val); 823 if (rc) 824 dev_err(&pdev->dev, "Error reading remote spad %d\n", QP_LINKS); 825 826 dev_dbg(&pdev->dev, "Remote QP link status = %x\n", val); 827 828 /* See if the remote side is up */ 829 if (1 << qp->qp_num & val) { 830 qp->qp_link = NTB_LINK_UP; 831 832 dev_info(&pdev->dev, "qp %d: Link Up\n", qp->qp_num); 833 if (qp->event_handler) 834 qp->event_handler(qp->cb_data, NTB_LINK_UP); 835 } else if (nt->transport_link == NTB_LINK_UP) 836 schedule_delayed_work(&qp->link_work, 837 msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT)); 838 } 839 840 static int ntb_transport_init_queue(struct ntb_transport *nt, 841 unsigned int qp_num) 842 { 843 struct ntb_transport_qp *qp; 844 unsigned int num_qps_mw, tx_size; 845 u8 mw_num, mw_max; 846 u64 qp_offset; 847 848 mw_max = ntb_max_mw(nt->ndev); 849 mw_num = QP_TO_MW(nt->ndev, qp_num); 850 851 qp = &nt->qps[qp_num]; 852 qp->qp_num = qp_num; 853 qp->transport = nt; 854 qp->ndev = nt->ndev; 855 qp->qp_link = NTB_LINK_DOWN; 856 qp->client_ready = NTB_LINK_DOWN; 857 qp->event_handler = NULL; 858 859 if (nt->max_qps % mw_max && mw_num < nt->max_qps % mw_max) 860 num_qps_mw = nt->max_qps / mw_max + 1; 861 else 862 num_qps_mw = nt->max_qps / mw_max; 863 864 tx_size = (unsigned int) ntb_get_mw_size(qp->ndev, mw_num) / num_qps_mw; 865 qp_offset = qp_num / mw_max * tx_size; 866 qp->tx_mw = ntb_get_mw_vbase(nt->ndev, mw_num) + qp_offset; 867 if (!qp->tx_mw) 868 return -EINVAL; 869 870 qp->tx_mw_phys = ntb_get_mw_base(qp->ndev, mw_num) + qp_offset; 871 if (!qp->tx_mw_phys) 872 return -EINVAL; 873 874 tx_size -= sizeof(struct ntb_rx_info); 875 qp->rx_info = qp->tx_mw + tx_size; 876 877 /* Due to housekeeping, there must be atleast 2 buffs */ 878 qp->tx_max_frame = min(transport_mtu, tx_size / 2); 879 qp->tx_max_entry = tx_size / qp->tx_max_frame; 880 881 if (ntb_query_debugfs(nt->ndev)) { 882 char debugfs_name[4]; 883 884 snprintf(debugfs_name, 4, "qp%d", qp_num); 885 qp->debugfs_dir = debugfs_create_dir(debugfs_name, 886 ntb_query_debugfs(nt->ndev)); 887 888 qp->debugfs_stats = debugfs_create_file("stats", S_IRUSR, 889 qp->debugfs_dir, qp, 890 &ntb_qp_debugfs_stats); 891 } 892 893 INIT_DELAYED_WORK(&qp->link_work, ntb_qp_link_work); 894 INIT_WORK(&qp->link_cleanup, ntb_qp_link_cleanup_work); 895 896 spin_lock_init(&qp->ntb_rx_pend_q_lock); 897 spin_lock_init(&qp->ntb_rx_free_q_lock); 898 spin_lock_init(&qp->ntb_tx_free_q_lock); 899 900 INIT_LIST_HEAD(&qp->rx_pend_q); 901 INIT_LIST_HEAD(&qp->rx_free_q); 902 INIT_LIST_HEAD(&qp->tx_free_q); 903 904 return 0; 905 } 906 907 int ntb_transport_init(struct pci_dev *pdev) 908 { 909 struct ntb_transport *nt; 910 int rc, i; 911 912 nt = kzalloc(sizeof(struct ntb_transport), GFP_KERNEL); 913 if (!nt) 914 return -ENOMEM; 915 916 nt->ndev = ntb_register_transport(pdev, nt); 917 if (!nt->ndev) { 918 rc = -EIO; 919 goto err; 920 } 921 922 nt->mw = kcalloc(ntb_max_mw(nt->ndev), sizeof(struct ntb_transport_mw), 923 GFP_KERNEL); 924 if (!nt->mw) { 925 rc = -ENOMEM; 926 goto err1; 927 } 928 929 if (max_num_clients) 930 nt->max_qps = min(ntb_max_cbs(nt->ndev), max_num_clients); 931 else 932 nt->max_qps = min(ntb_max_cbs(nt->ndev), ntb_max_mw(nt->ndev)); 933 934 nt->qps = kcalloc(nt->max_qps, sizeof(struct ntb_transport_qp), 935 GFP_KERNEL); 936 if (!nt->qps) { 937 rc = -ENOMEM; 938 goto err2; 939 } 940 941 nt->qp_bitmap = ((u64) 1 << nt->max_qps) - 1; 942 943 for (i = 0; i < nt->max_qps; i++) { 944 rc = ntb_transport_init_queue(nt, i); 945 if (rc) 946 goto err3; 947 } 948 949 INIT_DELAYED_WORK(&nt->link_work, ntb_transport_link_work); 950 INIT_WORK(&nt->link_cleanup, ntb_transport_link_cleanup_work); 951 952 rc = ntb_register_event_callback(nt->ndev, 953 ntb_transport_event_callback); 954 if (rc) 955 goto err3; 956 957 INIT_LIST_HEAD(&nt->client_devs); 958 rc = ntb_bus_init(nt); 959 if (rc) 960 goto err4; 961 962 if (ntb_hw_link_status(nt->ndev)) 963 schedule_delayed_work(&nt->link_work, 0); 964 965 return 0; 966 967 err4: 968 ntb_unregister_event_callback(nt->ndev); 969 err3: 970 kfree(nt->qps); 971 err2: 972 kfree(nt->mw); 973 err1: 974 ntb_unregister_transport(nt->ndev); 975 err: 976 kfree(nt); 977 return rc; 978 } 979 980 void ntb_transport_free(void *transport) 981 { 982 struct ntb_transport *nt = transport; 983 struct ntb_device *ndev = nt->ndev; 984 int i; 985 986 ntb_transport_link_cleanup(nt); 987 988 /* verify that all the qp's are freed */ 989 for (i = 0; i < nt->max_qps; i++) { 990 if (!test_bit(i, &nt->qp_bitmap)) 991 ntb_transport_free_queue(&nt->qps[i]); 992 debugfs_remove_recursive(nt->qps[i].debugfs_dir); 993 } 994 995 ntb_bus_remove(nt); 996 997 cancel_delayed_work_sync(&nt->link_work); 998 999 ntb_unregister_event_callback(ndev); 1000 1001 for (i = 0; i < ntb_max_mw(ndev); i++) 1002 ntb_free_mw(nt, i); 1003 1004 kfree(nt->qps); 1005 kfree(nt->mw); 1006 ntb_unregister_transport(ndev); 1007 kfree(nt); 1008 } 1009 1010 static void ntb_rx_copy_callback(void *data) 1011 { 1012 struct ntb_queue_entry *entry = data; 1013 struct ntb_transport_qp *qp = entry->qp; 1014 void *cb_data = entry->cb_data; 1015 unsigned int len = entry->len; 1016 struct ntb_payload_header *hdr = entry->rx_hdr; 1017 1018 /* Ensure that the data is fully copied out before clearing the flag */ 1019 wmb(); 1020 hdr->flags = 0; 1021 1022 iowrite32(entry->index, &qp->rx_info->entry); 1023 1024 ntb_list_add(&qp->ntb_rx_free_q_lock, &entry->entry, &qp->rx_free_q); 1025 1026 if (qp->rx_handler && qp->client_ready == NTB_LINK_UP) 1027 qp->rx_handler(qp, qp->cb_data, cb_data, len); 1028 } 1029 1030 static void ntb_memcpy_rx(struct ntb_queue_entry *entry, void *offset) 1031 { 1032 void *buf = entry->buf; 1033 size_t len = entry->len; 1034 1035 memcpy(buf, offset, len); 1036 1037 ntb_rx_copy_callback(entry); 1038 } 1039 1040 static void ntb_async_rx(struct ntb_queue_entry *entry, void *offset, 1041 size_t len) 1042 { 1043 struct dma_async_tx_descriptor *txd; 1044 struct ntb_transport_qp *qp = entry->qp; 1045 struct dma_chan *chan = qp->dma_chan; 1046 struct dma_device *device; 1047 size_t pay_off, buff_off; 1048 struct dmaengine_unmap_data *unmap; 1049 dma_cookie_t cookie; 1050 void *buf = entry->buf; 1051 1052 entry->len = len; 1053 1054 if (!chan) 1055 goto err; 1056 1057 if (len < copy_bytes) 1058 goto err_wait; 1059 1060 device = chan->device; 1061 pay_off = (size_t) offset & ~PAGE_MASK; 1062 buff_off = (size_t) buf & ~PAGE_MASK; 1063 1064 if (!is_dma_copy_aligned(device, pay_off, buff_off, len)) 1065 goto err_wait; 1066 1067 unmap = dmaengine_get_unmap_data(device->dev, 2, GFP_NOWAIT); 1068 if (!unmap) 1069 goto err_wait; 1070 1071 unmap->len = len; 1072 unmap->addr[0] = dma_map_page(device->dev, virt_to_page(offset), 1073 pay_off, len, DMA_TO_DEVICE); 1074 if (dma_mapping_error(device->dev, unmap->addr[0])) 1075 goto err_get_unmap; 1076 1077 unmap->to_cnt = 1; 1078 1079 unmap->addr[1] = dma_map_page(device->dev, virt_to_page(buf), 1080 buff_off, len, DMA_FROM_DEVICE); 1081 if (dma_mapping_error(device->dev, unmap->addr[1])) 1082 goto err_get_unmap; 1083 1084 unmap->from_cnt = 1; 1085 1086 txd = device->device_prep_dma_memcpy(chan, unmap->addr[1], 1087 unmap->addr[0], len, 1088 DMA_PREP_INTERRUPT); 1089 if (!txd) 1090 goto err_get_unmap; 1091 1092 txd->callback = ntb_rx_copy_callback; 1093 txd->callback_param = entry; 1094 dma_set_unmap(txd, unmap); 1095 1096 cookie = dmaengine_submit(txd); 1097 if (dma_submit_error(cookie)) 1098 goto err_set_unmap; 1099 1100 dmaengine_unmap_put(unmap); 1101 1102 qp->last_cookie = cookie; 1103 1104 qp->rx_async++; 1105 1106 return; 1107 1108 err_set_unmap: 1109 dmaengine_unmap_put(unmap); 1110 err_get_unmap: 1111 dmaengine_unmap_put(unmap); 1112 err_wait: 1113 /* If the callbacks come out of order, the writing of the index to the 1114 * last completed will be out of order. This may result in the 1115 * receive stalling forever. 1116 */ 1117 dma_sync_wait(chan, qp->last_cookie); 1118 err: 1119 ntb_memcpy_rx(entry, offset); 1120 qp->rx_memcpy++; 1121 } 1122 1123 static int ntb_process_rxc(struct ntb_transport_qp *qp) 1124 { 1125 struct ntb_payload_header *hdr; 1126 struct ntb_queue_entry *entry; 1127 void *offset; 1128 1129 offset = qp->rx_buff + qp->rx_max_frame * qp->rx_index; 1130 hdr = offset + qp->rx_max_frame - sizeof(struct ntb_payload_header); 1131 1132 entry = ntb_list_rm(&qp->ntb_rx_pend_q_lock, &qp->rx_pend_q); 1133 if (!entry) { 1134 dev_dbg(&ntb_query_pdev(qp->ndev)->dev, 1135 "no buffer - HDR ver %u, len %d, flags %x\n", 1136 hdr->ver, hdr->len, hdr->flags); 1137 qp->rx_err_no_buf++; 1138 return -ENOMEM; 1139 } 1140 1141 if (!(hdr->flags & DESC_DONE_FLAG)) { 1142 ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, 1143 &qp->rx_pend_q); 1144 qp->rx_ring_empty++; 1145 return -EAGAIN; 1146 } 1147 1148 if (hdr->ver != (u32) qp->rx_pkts) { 1149 dev_dbg(&ntb_query_pdev(qp->ndev)->dev, 1150 "qp %d: version mismatch, expected %llu - got %u\n", 1151 qp->qp_num, qp->rx_pkts, hdr->ver); 1152 ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, 1153 &qp->rx_pend_q); 1154 qp->rx_err_ver++; 1155 return -EIO; 1156 } 1157 1158 if (hdr->flags & LINK_DOWN_FLAG) { 1159 ntb_qp_link_down(qp); 1160 1161 goto err; 1162 } 1163 1164 dev_dbg(&ntb_query_pdev(qp->ndev)->dev, 1165 "rx offset %u, ver %u - %d payload received, buf size %d\n", 1166 qp->rx_index, hdr->ver, hdr->len, entry->len); 1167 1168 qp->rx_bytes += hdr->len; 1169 qp->rx_pkts++; 1170 1171 if (hdr->len > entry->len) { 1172 qp->rx_err_oflow++; 1173 dev_dbg(&ntb_query_pdev(qp->ndev)->dev, 1174 "RX overflow! Wanted %d got %d\n", 1175 hdr->len, entry->len); 1176 1177 goto err; 1178 } 1179 1180 entry->index = qp->rx_index; 1181 entry->rx_hdr = hdr; 1182 1183 ntb_async_rx(entry, offset, hdr->len); 1184 1185 out: 1186 qp->rx_index++; 1187 qp->rx_index %= qp->rx_max_entry; 1188 1189 return 0; 1190 1191 err: 1192 ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, &qp->rx_pend_q); 1193 /* Ensure that the data is fully copied out before clearing the flag */ 1194 wmb(); 1195 hdr->flags = 0; 1196 iowrite32(qp->rx_index, &qp->rx_info->entry); 1197 1198 goto out; 1199 } 1200 1201 static int ntb_transport_rxc_db(void *data, int db_num) 1202 { 1203 struct ntb_transport_qp *qp = data; 1204 int rc, i; 1205 1206 dev_dbg(&ntb_query_pdev(qp->ndev)->dev, "%s: doorbell %d received\n", 1207 __func__, db_num); 1208 1209 /* Limit the number of packets processed in a single interrupt to 1210 * provide fairness to others 1211 */ 1212 for (i = 0; i < qp->rx_max_entry; i++) { 1213 rc = ntb_process_rxc(qp); 1214 if (rc) 1215 break; 1216 } 1217 1218 if (qp->dma_chan) 1219 dma_async_issue_pending(qp->dma_chan); 1220 1221 return i; 1222 } 1223 1224 static void ntb_tx_copy_callback(void *data) 1225 { 1226 struct ntb_queue_entry *entry = data; 1227 struct ntb_transport_qp *qp = entry->qp; 1228 struct ntb_payload_header __iomem *hdr = entry->tx_hdr; 1229 1230 /* Ensure that the data is fully copied out before setting the flags */ 1231 wmb(); 1232 iowrite32(entry->flags | DESC_DONE_FLAG, &hdr->flags); 1233 1234 ntb_ring_doorbell(qp->ndev, qp->qp_num); 1235 1236 /* The entry length can only be zero if the packet is intended to be a 1237 * "link down" or similar. Since no payload is being sent in these 1238 * cases, there is nothing to add to the completion queue. 1239 */ 1240 if (entry->len > 0) { 1241 qp->tx_bytes += entry->len; 1242 1243 if (qp->tx_handler) 1244 qp->tx_handler(qp, qp->cb_data, entry->cb_data, 1245 entry->len); 1246 } 1247 1248 ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, &qp->tx_free_q); 1249 } 1250 1251 static void ntb_memcpy_tx(struct ntb_queue_entry *entry, void __iomem *offset) 1252 { 1253 memcpy_toio(offset, entry->buf, entry->len); 1254 1255 ntb_tx_copy_callback(entry); 1256 } 1257 1258 static void ntb_async_tx(struct ntb_transport_qp *qp, 1259 struct ntb_queue_entry *entry) 1260 { 1261 struct ntb_payload_header __iomem *hdr; 1262 struct dma_async_tx_descriptor *txd; 1263 struct dma_chan *chan = qp->dma_chan; 1264 struct dma_device *device; 1265 size_t dest_off, buff_off; 1266 struct dmaengine_unmap_data *unmap; 1267 dma_addr_t dest; 1268 dma_cookie_t cookie; 1269 void __iomem *offset; 1270 size_t len = entry->len; 1271 void *buf = entry->buf; 1272 1273 offset = qp->tx_mw + qp->tx_max_frame * qp->tx_index; 1274 hdr = offset + qp->tx_max_frame - sizeof(struct ntb_payload_header); 1275 entry->tx_hdr = hdr; 1276 1277 iowrite32(entry->len, &hdr->len); 1278 iowrite32((u32) qp->tx_pkts, &hdr->ver); 1279 1280 if (!chan) 1281 goto err; 1282 1283 if (len < copy_bytes) 1284 goto err; 1285 1286 device = chan->device; 1287 dest = qp->tx_mw_phys + qp->tx_max_frame * qp->tx_index; 1288 buff_off = (size_t) buf & ~PAGE_MASK; 1289 dest_off = (size_t) dest & ~PAGE_MASK; 1290 1291 if (!is_dma_copy_aligned(device, buff_off, dest_off, len)) 1292 goto err; 1293 1294 unmap = dmaengine_get_unmap_data(device->dev, 1, GFP_NOWAIT); 1295 if (!unmap) 1296 goto err; 1297 1298 unmap->len = len; 1299 unmap->addr[0] = dma_map_page(device->dev, virt_to_page(buf), 1300 buff_off, len, DMA_TO_DEVICE); 1301 if (dma_mapping_error(device->dev, unmap->addr[0])) 1302 goto err_get_unmap; 1303 1304 unmap->to_cnt = 1; 1305 1306 txd = device->device_prep_dma_memcpy(chan, dest, unmap->addr[0], len, 1307 DMA_PREP_INTERRUPT); 1308 if (!txd) 1309 goto err_get_unmap; 1310 1311 txd->callback = ntb_tx_copy_callback; 1312 txd->callback_param = entry; 1313 dma_set_unmap(txd, unmap); 1314 1315 cookie = dmaengine_submit(txd); 1316 if (dma_submit_error(cookie)) 1317 goto err_set_unmap; 1318 1319 dmaengine_unmap_put(unmap); 1320 1321 dma_async_issue_pending(chan); 1322 qp->tx_async++; 1323 1324 return; 1325 err_set_unmap: 1326 dmaengine_unmap_put(unmap); 1327 err_get_unmap: 1328 dmaengine_unmap_put(unmap); 1329 err: 1330 ntb_memcpy_tx(entry, offset); 1331 qp->tx_memcpy++; 1332 } 1333 1334 static int ntb_process_tx(struct ntb_transport_qp *qp, 1335 struct ntb_queue_entry *entry) 1336 { 1337 dev_dbg(&ntb_query_pdev(qp->ndev)->dev, "%lld - tx %u, entry len %d flags %x buff %p\n", 1338 qp->tx_pkts, qp->tx_index, entry->len, entry->flags, 1339 entry->buf); 1340 if (qp->tx_index == qp->remote_rx_info->entry) { 1341 qp->tx_ring_full++; 1342 return -EAGAIN; 1343 } 1344 1345 if (entry->len > qp->tx_max_frame - sizeof(struct ntb_payload_header)) { 1346 if (qp->tx_handler) 1347 qp->tx_handler(qp->cb_data, qp, NULL, -EIO); 1348 1349 ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, 1350 &qp->tx_free_q); 1351 return 0; 1352 } 1353 1354 ntb_async_tx(qp, entry); 1355 1356 qp->tx_index++; 1357 qp->tx_index %= qp->tx_max_entry; 1358 1359 qp->tx_pkts++; 1360 1361 return 0; 1362 } 1363 1364 static void ntb_send_link_down(struct ntb_transport_qp *qp) 1365 { 1366 struct pci_dev *pdev = ntb_query_pdev(qp->ndev); 1367 struct ntb_queue_entry *entry; 1368 int i, rc; 1369 1370 if (qp->qp_link == NTB_LINK_DOWN) 1371 return; 1372 1373 qp->qp_link = NTB_LINK_DOWN; 1374 dev_info(&pdev->dev, "qp %d: Link Down\n", qp->qp_num); 1375 1376 for (i = 0; i < NTB_LINK_DOWN_TIMEOUT; i++) { 1377 entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q); 1378 if (entry) 1379 break; 1380 msleep(100); 1381 } 1382 1383 if (!entry) 1384 return; 1385 1386 entry->cb_data = NULL; 1387 entry->buf = NULL; 1388 entry->len = 0; 1389 entry->flags = LINK_DOWN_FLAG; 1390 1391 rc = ntb_process_tx(qp, entry); 1392 if (rc) 1393 dev_err(&pdev->dev, "ntb: QP%d unable to send linkdown msg\n", 1394 qp->qp_num); 1395 } 1396 1397 /** 1398 * ntb_transport_create_queue - Create a new NTB transport layer queue 1399 * @rx_handler: receive callback function 1400 * @tx_handler: transmit callback function 1401 * @event_handler: event callback function 1402 * 1403 * Create a new NTB transport layer queue and provide the queue with a callback 1404 * routine for both transmit and receive. The receive callback routine will be 1405 * used to pass up data when the transport has received it on the queue. The 1406 * transmit callback routine will be called when the transport has completed the 1407 * transmission of the data on the queue and the data is ready to be freed. 1408 * 1409 * RETURNS: pointer to newly created ntb_queue, NULL on error. 1410 */ 1411 struct ntb_transport_qp * 1412 ntb_transport_create_queue(void *data, struct pci_dev *pdev, 1413 const struct ntb_queue_handlers *handlers) 1414 { 1415 struct ntb_queue_entry *entry; 1416 struct ntb_transport_qp *qp; 1417 struct ntb_transport *nt; 1418 unsigned int free_queue; 1419 int rc, i; 1420 1421 nt = ntb_find_transport(pdev); 1422 if (!nt) 1423 goto err; 1424 1425 free_queue = ffs(nt->qp_bitmap); 1426 if (!free_queue) 1427 goto err; 1428 1429 /* decrement free_queue to make it zero based */ 1430 free_queue--; 1431 1432 clear_bit(free_queue, &nt->qp_bitmap); 1433 1434 qp = &nt->qps[free_queue]; 1435 qp->cb_data = data; 1436 qp->rx_handler = handlers->rx_handler; 1437 qp->tx_handler = handlers->tx_handler; 1438 qp->event_handler = handlers->event_handler; 1439 1440 dmaengine_get(); 1441 qp->dma_chan = dma_find_channel(DMA_MEMCPY); 1442 if (!qp->dma_chan) { 1443 dmaengine_put(); 1444 dev_info(&pdev->dev, "Unable to allocate DMA channel, using CPU instead\n"); 1445 } 1446 1447 for (i = 0; i < NTB_QP_DEF_NUM_ENTRIES; i++) { 1448 entry = kzalloc(sizeof(struct ntb_queue_entry), GFP_ATOMIC); 1449 if (!entry) 1450 goto err1; 1451 1452 entry->qp = qp; 1453 ntb_list_add(&qp->ntb_rx_free_q_lock, &entry->entry, 1454 &qp->rx_free_q); 1455 } 1456 1457 for (i = 0; i < NTB_QP_DEF_NUM_ENTRIES; i++) { 1458 entry = kzalloc(sizeof(struct ntb_queue_entry), GFP_ATOMIC); 1459 if (!entry) 1460 goto err2; 1461 1462 entry->qp = qp; 1463 ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, 1464 &qp->tx_free_q); 1465 } 1466 1467 rc = ntb_register_db_callback(qp->ndev, free_queue, qp, 1468 ntb_transport_rxc_db); 1469 if (rc) 1470 goto err2; 1471 1472 dev_info(&pdev->dev, "NTB Transport QP %d created\n", qp->qp_num); 1473 1474 return qp; 1475 1476 err2: 1477 while ((entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q))) 1478 kfree(entry); 1479 err1: 1480 while ((entry = ntb_list_rm(&qp->ntb_rx_free_q_lock, &qp->rx_free_q))) 1481 kfree(entry); 1482 if (qp->dma_chan) 1483 dmaengine_put(); 1484 set_bit(free_queue, &nt->qp_bitmap); 1485 err: 1486 return NULL; 1487 } 1488 EXPORT_SYMBOL_GPL(ntb_transport_create_queue); 1489 1490 /** 1491 * ntb_transport_free_queue - Frees NTB transport queue 1492 * @qp: NTB queue to be freed 1493 * 1494 * Frees NTB transport queue 1495 */ 1496 void ntb_transport_free_queue(struct ntb_transport_qp *qp) 1497 { 1498 struct pci_dev *pdev; 1499 struct ntb_queue_entry *entry; 1500 1501 if (!qp) 1502 return; 1503 1504 pdev = ntb_query_pdev(qp->ndev); 1505 1506 if (qp->dma_chan) { 1507 struct dma_chan *chan = qp->dma_chan; 1508 /* Putting the dma_chan to NULL will force any new traffic to be 1509 * processed by the CPU instead of the DAM engine 1510 */ 1511 qp->dma_chan = NULL; 1512 1513 /* Try to be nice and wait for any queued DMA engine 1514 * transactions to process before smashing it with a rock 1515 */ 1516 dma_sync_wait(chan, qp->last_cookie); 1517 dmaengine_terminate_all(chan); 1518 dmaengine_put(); 1519 } 1520 1521 ntb_unregister_db_callback(qp->ndev, qp->qp_num); 1522 1523 cancel_delayed_work_sync(&qp->link_work); 1524 1525 while ((entry = ntb_list_rm(&qp->ntb_rx_free_q_lock, &qp->rx_free_q))) 1526 kfree(entry); 1527 1528 while ((entry = ntb_list_rm(&qp->ntb_rx_pend_q_lock, &qp->rx_pend_q))) { 1529 dev_warn(&pdev->dev, "Freeing item from a non-empty queue\n"); 1530 kfree(entry); 1531 } 1532 1533 while ((entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q))) 1534 kfree(entry); 1535 1536 set_bit(qp->qp_num, &qp->transport->qp_bitmap); 1537 1538 dev_info(&pdev->dev, "NTB Transport QP %d freed\n", qp->qp_num); 1539 } 1540 EXPORT_SYMBOL_GPL(ntb_transport_free_queue); 1541 1542 /** 1543 * ntb_transport_rx_remove - Dequeues enqueued rx packet 1544 * @qp: NTB queue to be freed 1545 * @len: pointer to variable to write enqueued buffers length 1546 * 1547 * Dequeues unused buffers from receive queue. Should only be used during 1548 * shutdown of qp. 1549 * 1550 * RETURNS: NULL error value on error, or void* for success. 1551 */ 1552 void *ntb_transport_rx_remove(struct ntb_transport_qp *qp, unsigned int *len) 1553 { 1554 struct ntb_queue_entry *entry; 1555 void *buf; 1556 1557 if (!qp || qp->client_ready == NTB_LINK_UP) 1558 return NULL; 1559 1560 entry = ntb_list_rm(&qp->ntb_rx_pend_q_lock, &qp->rx_pend_q); 1561 if (!entry) 1562 return NULL; 1563 1564 buf = entry->cb_data; 1565 *len = entry->len; 1566 1567 ntb_list_add(&qp->ntb_rx_free_q_lock, &entry->entry, &qp->rx_free_q); 1568 1569 return buf; 1570 } 1571 EXPORT_SYMBOL_GPL(ntb_transport_rx_remove); 1572 1573 /** 1574 * ntb_transport_rx_enqueue - Enqueue a new NTB queue entry 1575 * @qp: NTB transport layer queue the entry is to be enqueued on 1576 * @cb: per buffer pointer for callback function to use 1577 * @data: pointer to data buffer that incoming packets will be copied into 1578 * @len: length of the data buffer 1579 * 1580 * Enqueue a new receive buffer onto the transport queue into which a NTB 1581 * payload can be received into. 1582 * 1583 * RETURNS: An appropriate -ERRNO error value on error, or zero for success. 1584 */ 1585 int ntb_transport_rx_enqueue(struct ntb_transport_qp *qp, void *cb, void *data, 1586 unsigned int len) 1587 { 1588 struct ntb_queue_entry *entry; 1589 1590 if (!qp) 1591 return -EINVAL; 1592 1593 entry = ntb_list_rm(&qp->ntb_rx_free_q_lock, &qp->rx_free_q); 1594 if (!entry) 1595 return -ENOMEM; 1596 1597 entry->cb_data = cb; 1598 entry->buf = data; 1599 entry->len = len; 1600 1601 ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, &qp->rx_pend_q); 1602 1603 return 0; 1604 } 1605 EXPORT_SYMBOL_GPL(ntb_transport_rx_enqueue); 1606 1607 /** 1608 * ntb_transport_tx_enqueue - Enqueue a new NTB queue entry 1609 * @qp: NTB transport layer queue the entry is to be enqueued on 1610 * @cb: per buffer pointer for callback function to use 1611 * @data: pointer to data buffer that will be sent 1612 * @len: length of the data buffer 1613 * 1614 * Enqueue a new transmit buffer onto the transport queue from which a NTB 1615 * payload will be transmitted. This assumes that a lock is being held to 1616 * serialize access to the qp. 1617 * 1618 * RETURNS: An appropriate -ERRNO error value on error, or zero for success. 1619 */ 1620 int ntb_transport_tx_enqueue(struct ntb_transport_qp *qp, void *cb, void *data, 1621 unsigned int len) 1622 { 1623 struct ntb_queue_entry *entry; 1624 int rc; 1625 1626 if (!qp || qp->qp_link != NTB_LINK_UP || !len) 1627 return -EINVAL; 1628 1629 entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q); 1630 if (!entry) { 1631 qp->tx_err_no_buf++; 1632 return -ENOMEM; 1633 } 1634 1635 entry->cb_data = cb; 1636 entry->buf = data; 1637 entry->len = len; 1638 entry->flags = 0; 1639 1640 rc = ntb_process_tx(qp, entry); 1641 if (rc) 1642 ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, 1643 &qp->tx_free_q); 1644 1645 return rc; 1646 } 1647 EXPORT_SYMBOL_GPL(ntb_transport_tx_enqueue); 1648 1649 /** 1650 * ntb_transport_link_up - Notify NTB transport of client readiness to use queue 1651 * @qp: NTB transport layer queue to be enabled 1652 * 1653 * Notify NTB transport layer of client readiness to use queue 1654 */ 1655 void ntb_transport_link_up(struct ntb_transport_qp *qp) 1656 { 1657 if (!qp) 1658 return; 1659 1660 qp->client_ready = NTB_LINK_UP; 1661 1662 if (qp->transport->transport_link == NTB_LINK_UP) 1663 schedule_delayed_work(&qp->link_work, 0); 1664 } 1665 EXPORT_SYMBOL_GPL(ntb_transport_link_up); 1666 1667 /** 1668 * ntb_transport_link_down - Notify NTB transport to no longer enqueue data 1669 * @qp: NTB transport layer queue to be disabled 1670 * 1671 * Notify NTB transport layer of client's desire to no longer receive data on 1672 * transport queue specified. It is the client's responsibility to ensure all 1673 * entries on queue are purged or otherwise handled appropriately. 1674 */ 1675 void ntb_transport_link_down(struct ntb_transport_qp *qp) 1676 { 1677 struct pci_dev *pdev; 1678 int rc, val; 1679 1680 if (!qp) 1681 return; 1682 1683 pdev = ntb_query_pdev(qp->ndev); 1684 qp->client_ready = NTB_LINK_DOWN; 1685 1686 rc = ntb_read_local_spad(qp->ndev, QP_LINKS, &val); 1687 if (rc) { 1688 dev_err(&pdev->dev, "Error reading spad %d\n", QP_LINKS); 1689 return; 1690 } 1691 1692 rc = ntb_write_remote_spad(qp->ndev, QP_LINKS, 1693 val & ~(1 << qp->qp_num)); 1694 if (rc) 1695 dev_err(&pdev->dev, "Error writing %x to remote spad %d\n", 1696 val & ~(1 << qp->qp_num), QP_LINKS); 1697 1698 if (qp->qp_link == NTB_LINK_UP) 1699 ntb_send_link_down(qp); 1700 else 1701 cancel_delayed_work_sync(&qp->link_work); 1702 } 1703 EXPORT_SYMBOL_GPL(ntb_transport_link_down); 1704 1705 /** 1706 * ntb_transport_link_query - Query transport link state 1707 * @qp: NTB transport layer queue to be queried 1708 * 1709 * Query connectivity to the remote system of the NTB transport queue 1710 * 1711 * RETURNS: true for link up or false for link down 1712 */ 1713 bool ntb_transport_link_query(struct ntb_transport_qp *qp) 1714 { 1715 if (!qp) 1716 return false; 1717 1718 return qp->qp_link == NTB_LINK_UP; 1719 } 1720 EXPORT_SYMBOL_GPL(ntb_transport_link_query); 1721 1722 /** 1723 * ntb_transport_qp_num - Query the qp number 1724 * @qp: NTB transport layer queue to be queried 1725 * 1726 * Query qp number of the NTB transport queue 1727 * 1728 * RETURNS: a zero based number specifying the qp number 1729 */ 1730 unsigned char ntb_transport_qp_num(struct ntb_transport_qp *qp) 1731 { 1732 if (!qp) 1733 return 0; 1734 1735 return qp->qp_num; 1736 } 1737 EXPORT_SYMBOL_GPL(ntb_transport_qp_num); 1738 1739 /** 1740 * ntb_transport_max_size - Query the max payload size of a qp 1741 * @qp: NTB transport layer queue to be queried 1742 * 1743 * Query the maximum payload size permissible on the given qp 1744 * 1745 * RETURNS: the max payload size of a qp 1746 */ 1747 unsigned int ntb_transport_max_size(struct ntb_transport_qp *qp) 1748 { 1749 unsigned int max; 1750 1751 if (!qp) 1752 return 0; 1753 1754 if (!qp->dma_chan) 1755 return qp->tx_max_frame - sizeof(struct ntb_payload_header); 1756 1757 /* If DMA engine usage is possible, try to find the max size for that */ 1758 max = qp->tx_max_frame - sizeof(struct ntb_payload_header); 1759 max -= max % (1 << qp->dma_chan->device->copy_align); 1760 1761 return max; 1762 } 1763 EXPORT_SYMBOL_GPL(ntb_transport_max_size); 1764