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/dma-mapping.h> 51 #include <linux/errno.h> 52 #include <linux/export.h> 53 #include <linux/interrupt.h> 54 #include <linux/module.h> 55 #include <linux/pci.h> 56 #include <linux/slab.h> 57 #include <linux/types.h> 58 #include <linux/ntb.h> 59 #include "ntb_hw.h" 60 61 #define NTB_TRANSPORT_VERSION 1 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 = 2; 68 module_param(max_num_clients, byte, 0644); 69 MODULE_PARM_DESC(max_num_clients, "Maximum number of NTB transport clients"); 70 71 struct ntb_queue_entry { 72 /* ntb_queue list reference */ 73 struct list_head entry; 74 /* pointers to data to be transfered */ 75 void *cb_data; 76 void *buf; 77 unsigned int len; 78 unsigned int flags; 79 }; 80 81 struct ntb_transport_qp { 82 struct ntb_transport *transport; 83 struct ntb_device *ndev; 84 void *cb_data; 85 86 bool client_ready; 87 bool qp_link; 88 u8 qp_num; /* Only 64 QP's are allowed. 0-63 */ 89 90 void (*tx_handler) (struct ntb_transport_qp *qp, void *qp_data, 91 void *data, int len); 92 struct list_head tx_free_q; 93 spinlock_t ntb_tx_free_q_lock; 94 void *tx_mw_begin; 95 void *tx_mw_end; 96 void *tx_offset; 97 unsigned int tx_max_frame; 98 99 void (*rx_handler) (struct ntb_transport_qp *qp, void *qp_data, 100 void *data, int len); 101 struct tasklet_struct rx_work; 102 struct list_head rx_pend_q; 103 struct list_head rx_free_q; 104 spinlock_t ntb_rx_pend_q_lock; 105 spinlock_t ntb_rx_free_q_lock; 106 void *rx_buff_begin; 107 void *rx_buff_end; 108 void *rx_offset; 109 unsigned int rx_max_frame; 110 111 void (*event_handler) (void *data, int status); 112 struct delayed_work link_work; 113 struct work_struct link_cleanup; 114 115 struct dentry *debugfs_dir; 116 struct dentry *debugfs_stats; 117 118 /* Stats */ 119 u64 rx_bytes; 120 u64 rx_pkts; 121 u64 rx_ring_empty; 122 u64 rx_err_no_buf; 123 u64 rx_err_oflow; 124 u64 rx_err_ver; 125 u64 tx_bytes; 126 u64 tx_pkts; 127 u64 tx_ring_full; 128 }; 129 130 struct ntb_transport_mw { 131 size_t size; 132 void *virt_addr; 133 dma_addr_t dma_addr; 134 }; 135 136 struct ntb_transport_client_dev { 137 struct list_head entry; 138 struct device dev; 139 }; 140 141 struct ntb_transport { 142 struct list_head entry; 143 struct list_head client_devs; 144 145 struct ntb_device *ndev; 146 struct ntb_transport_mw mw[NTB_NUM_MW]; 147 struct ntb_transport_qp *qps; 148 unsigned int max_qps; 149 unsigned long qp_bitmap; 150 bool transport_link; 151 struct delayed_work link_work; 152 struct work_struct link_cleanup; 153 struct dentry *debugfs_dir; 154 }; 155 156 enum { 157 DESC_DONE_FLAG = 1 << 0, 158 LINK_DOWN_FLAG = 1 << 1, 159 }; 160 161 struct ntb_payload_header { 162 u64 ver; 163 unsigned int len; 164 unsigned int flags; 165 }; 166 167 enum { 168 VERSION = 0, 169 MW0_SZ, 170 MW1_SZ, 171 NUM_QPS, 172 QP_LINKS, 173 MAX_SPAD, 174 }; 175 176 #define QP_TO_MW(qp) ((qp) % NTB_NUM_MW) 177 #define NTB_QP_DEF_NUM_ENTRIES 100 178 #define NTB_LINK_DOWN_TIMEOUT 10 179 180 static int ntb_match_bus(struct device *dev, struct device_driver *drv) 181 { 182 return !strncmp(dev_name(dev), drv->name, strlen(drv->name)); 183 } 184 185 static int ntb_client_probe(struct device *dev) 186 { 187 const struct ntb_client *drv = container_of(dev->driver, 188 struct ntb_client, driver); 189 struct pci_dev *pdev = container_of(dev->parent, struct pci_dev, dev); 190 int rc = -EINVAL; 191 192 get_device(dev); 193 if (drv && drv->probe) 194 rc = drv->probe(pdev); 195 if (rc) 196 put_device(dev); 197 198 return rc; 199 } 200 201 static int ntb_client_remove(struct device *dev) 202 { 203 const struct ntb_client *drv = container_of(dev->driver, 204 struct ntb_client, driver); 205 struct pci_dev *pdev = container_of(dev->parent, struct pci_dev, dev); 206 207 if (drv && drv->remove) 208 drv->remove(pdev); 209 210 put_device(dev); 211 212 return 0; 213 } 214 215 struct bus_type ntb_bus_type = { 216 .name = "ntb_bus", 217 .match = ntb_match_bus, 218 .probe = ntb_client_probe, 219 .remove = ntb_client_remove, 220 }; 221 222 static LIST_HEAD(ntb_transport_list); 223 224 static int ntb_bus_init(struct ntb_transport *nt) 225 { 226 if (list_empty(&ntb_transport_list)) { 227 int rc = bus_register(&ntb_bus_type); 228 if (rc) 229 return rc; 230 } 231 232 list_add(&nt->entry, &ntb_transport_list); 233 234 return 0; 235 } 236 237 static void ntb_bus_remove(struct ntb_transport *nt) 238 { 239 struct ntb_transport_client_dev *client_dev, *cd; 240 241 list_for_each_entry_safe(client_dev, cd, &nt->client_devs, entry) { 242 dev_err(client_dev->dev.parent, "%s still attached to bus, removing\n", 243 dev_name(&client_dev->dev)); 244 list_del(&client_dev->entry); 245 device_unregister(&client_dev->dev); 246 } 247 248 list_del(&nt->entry); 249 250 if (list_empty(&ntb_transport_list)) 251 bus_unregister(&ntb_bus_type); 252 } 253 254 static void ntb_client_release(struct device *dev) 255 { 256 struct ntb_transport_client_dev *client_dev; 257 client_dev = container_of(dev, struct ntb_transport_client_dev, dev); 258 259 kfree(client_dev); 260 } 261 262 /** 263 * ntb_unregister_client_dev - Unregister NTB client device 264 * @device_name: Name of NTB client device 265 * 266 * Unregister an NTB client device with the NTB transport layer 267 */ 268 void ntb_unregister_client_dev(char *device_name) 269 { 270 struct ntb_transport_client_dev *client, *cd; 271 struct ntb_transport *nt; 272 273 list_for_each_entry(nt, &ntb_transport_list, entry) 274 list_for_each_entry_safe(client, cd, &nt->client_devs, entry) 275 if (!strncmp(dev_name(&client->dev), device_name, 276 strlen(device_name))) { 277 list_del(&client->entry); 278 device_unregister(&client->dev); 279 } 280 } 281 EXPORT_SYMBOL_GPL(ntb_unregister_client_dev); 282 283 /** 284 * ntb_register_client_dev - Register NTB client device 285 * @device_name: Name of NTB client device 286 * 287 * Register an NTB client device with the NTB transport layer 288 */ 289 int ntb_register_client_dev(char *device_name) 290 { 291 struct ntb_transport_client_dev *client_dev; 292 struct ntb_transport *nt; 293 int rc; 294 295 if (list_empty(&ntb_transport_list)) 296 return -ENODEV; 297 298 list_for_each_entry(nt, &ntb_transport_list, entry) { 299 struct device *dev; 300 301 client_dev = kzalloc(sizeof(struct ntb_transport_client_dev), 302 GFP_KERNEL); 303 if (!client_dev) { 304 rc = -ENOMEM; 305 goto err; 306 } 307 308 dev = &client_dev->dev; 309 310 /* setup and register client devices */ 311 dev_set_name(dev, "%s", device_name); 312 dev->bus = &ntb_bus_type; 313 dev->release = ntb_client_release; 314 dev->parent = &ntb_query_pdev(nt->ndev)->dev; 315 316 rc = device_register(dev); 317 if (rc) { 318 kfree(client_dev); 319 goto err; 320 } 321 322 list_add_tail(&client_dev->entry, &nt->client_devs); 323 } 324 325 return 0; 326 327 err: 328 ntb_unregister_client_dev(device_name); 329 330 return rc; 331 } 332 EXPORT_SYMBOL_GPL(ntb_register_client_dev); 333 334 /** 335 * ntb_register_client - Register NTB client driver 336 * @drv: NTB client driver to be registered 337 * 338 * Register an NTB client driver with the NTB transport layer 339 * 340 * RETURNS: An appropriate -ERRNO error value on error, or zero for success. 341 */ 342 int ntb_register_client(struct ntb_client *drv) 343 { 344 drv->driver.bus = &ntb_bus_type; 345 346 if (list_empty(&ntb_transport_list)) 347 return -ENODEV; 348 349 return driver_register(&drv->driver); 350 } 351 EXPORT_SYMBOL_GPL(ntb_register_client); 352 353 /** 354 * ntb_unregister_client - Unregister NTB client driver 355 * @drv: NTB client driver to be unregistered 356 * 357 * Unregister an NTB client driver with the NTB transport layer 358 * 359 * RETURNS: An appropriate -ERRNO error value on error, or zero for success. 360 */ 361 void ntb_unregister_client(struct ntb_client *drv) 362 { 363 driver_unregister(&drv->driver); 364 } 365 EXPORT_SYMBOL_GPL(ntb_unregister_client); 366 367 static int debugfs_open(struct inode *inode, struct file *filp) 368 { 369 filp->private_data = inode->i_private; 370 return 0; 371 } 372 373 static ssize_t debugfs_read(struct file *filp, char __user *ubuf, size_t count, 374 loff_t *offp) 375 { 376 struct ntb_transport_qp *qp; 377 char buf[1024]; 378 ssize_t ret, out_offset, out_count; 379 380 out_count = 1024; 381 382 qp = filp->private_data; 383 out_offset = 0; 384 out_offset += snprintf(buf + out_offset, out_count - out_offset, 385 "NTB QP stats\n"); 386 out_offset += snprintf(buf + out_offset, out_count - out_offset, 387 "rx_bytes - \t%llu\n", qp->rx_bytes); 388 out_offset += snprintf(buf + out_offset, out_count - out_offset, 389 "rx_pkts - \t%llu\n", qp->rx_pkts); 390 out_offset += snprintf(buf + out_offset, out_count - out_offset, 391 "rx_ring_empty - %llu\n", qp->rx_ring_empty); 392 out_offset += snprintf(buf + out_offset, out_count - out_offset, 393 "rx_err_no_buf - %llu\n", qp->rx_err_no_buf); 394 out_offset += snprintf(buf + out_offset, out_count - out_offset, 395 "rx_err_oflow - \t%llu\n", qp->rx_err_oflow); 396 out_offset += snprintf(buf + out_offset, out_count - out_offset, 397 "rx_err_ver - \t%llu\n", qp->rx_err_ver); 398 out_offset += snprintf(buf + out_offset, out_count - out_offset, 399 "rx_buff_begin - %p\n", qp->rx_buff_begin); 400 out_offset += snprintf(buf + out_offset, out_count - out_offset, 401 "rx_offset - \t%p\n", qp->rx_offset); 402 out_offset += snprintf(buf + out_offset, out_count - out_offset, 403 "rx_buff_end - \t%p\n", qp->rx_buff_end); 404 405 out_offset += snprintf(buf + out_offset, out_count - out_offset, 406 "tx_bytes - \t%llu\n", qp->tx_bytes); 407 out_offset += snprintf(buf + out_offset, out_count - out_offset, 408 "tx_pkts - \t%llu\n", qp->tx_pkts); 409 out_offset += snprintf(buf + out_offset, out_count - out_offset, 410 "tx_ring_full - \t%llu\n", qp->tx_ring_full); 411 out_offset += snprintf(buf + out_offset, out_count - out_offset, 412 "tx_mw_begin - \t%p\n", qp->tx_mw_begin); 413 out_offset += snprintf(buf + out_offset, out_count - out_offset, 414 "tx_offset - \t%p\n", qp->tx_offset); 415 out_offset += snprintf(buf + out_offset, out_count - out_offset, 416 "tx_mw_end - \t%p\n", qp->tx_mw_end); 417 418 out_offset += snprintf(buf + out_offset, out_count - out_offset, 419 "QP Link %s\n", (qp->qp_link == NTB_LINK_UP) ? 420 "Up" : "Down"); 421 422 ret = simple_read_from_buffer(ubuf, count, offp, buf, out_offset); 423 return ret; 424 } 425 426 static const struct file_operations ntb_qp_debugfs_stats = { 427 .owner = THIS_MODULE, 428 .open = debugfs_open, 429 .read = debugfs_read, 430 }; 431 432 static void ntb_list_add(spinlock_t *lock, struct list_head *entry, 433 struct list_head *list) 434 { 435 unsigned long flags; 436 437 spin_lock_irqsave(lock, flags); 438 list_add_tail(entry, list); 439 spin_unlock_irqrestore(lock, flags); 440 } 441 442 static struct ntb_queue_entry *ntb_list_rm(spinlock_t *lock, 443 struct list_head *list) 444 { 445 struct ntb_queue_entry *entry; 446 unsigned long flags; 447 448 spin_lock_irqsave(lock, flags); 449 if (list_empty(list)) { 450 entry = NULL; 451 goto out; 452 } 453 entry = list_first_entry(list, struct ntb_queue_entry, entry); 454 list_del(&entry->entry); 455 out: 456 spin_unlock_irqrestore(lock, flags); 457 458 return entry; 459 } 460 461 static void ntb_transport_setup_qp_mw(struct ntb_transport *nt, 462 unsigned int qp_num) 463 { 464 struct ntb_transport_qp *qp = &nt->qps[qp_num]; 465 unsigned int rx_size, num_qps_mw; 466 u8 mw_num = QP_TO_MW(qp_num); 467 void *offset; 468 469 WARN_ON(nt->mw[mw_num].virt_addr == 0); 470 471 if (nt->max_qps % NTB_NUM_MW && mw_num < nt->max_qps % NTB_NUM_MW) 472 num_qps_mw = nt->max_qps / NTB_NUM_MW + 1; 473 else 474 num_qps_mw = nt->max_qps / NTB_NUM_MW; 475 476 rx_size = nt->mw[mw_num].size / num_qps_mw; 477 qp->rx_buff_begin = nt->mw[mw_num].virt_addr + 478 (qp_num / NTB_NUM_MW * rx_size); 479 qp->rx_buff_end = qp->rx_buff_begin + rx_size; 480 qp->rx_offset = qp->rx_buff_begin; 481 qp->rx_max_frame = min(transport_mtu, rx_size); 482 483 /* setup the hdr offsets with 0's */ 484 for (offset = qp->rx_buff_begin + qp->rx_max_frame - 485 sizeof(struct ntb_payload_header); 486 offset < qp->rx_buff_end; offset += qp->rx_max_frame) 487 memset(offset, 0, sizeof(struct ntb_payload_header)); 488 489 qp->rx_pkts = 0; 490 qp->tx_pkts = 0; 491 } 492 493 static int ntb_set_mw(struct ntb_transport *nt, int num_mw, unsigned int size) 494 { 495 struct ntb_transport_mw *mw = &nt->mw[num_mw]; 496 struct pci_dev *pdev = ntb_query_pdev(nt->ndev); 497 498 /* Alloc memory for receiving data. Must be 4k aligned */ 499 mw->size = ALIGN(size, 4096); 500 501 mw->virt_addr = dma_alloc_coherent(&pdev->dev, mw->size, &mw->dma_addr, 502 GFP_KERNEL); 503 if (!mw->virt_addr) { 504 dev_err(&pdev->dev, "Unable to allocate MW buffer of size %d\n", 505 (int) mw->size); 506 return -ENOMEM; 507 } 508 509 /* Notify HW the memory location of the receive buffer */ 510 ntb_set_mw_addr(nt->ndev, num_mw, mw->dma_addr); 511 512 return 0; 513 } 514 515 static void ntb_qp_link_cleanup(struct work_struct *work) 516 { 517 struct ntb_transport_qp *qp = container_of(work, 518 struct ntb_transport_qp, 519 link_cleanup); 520 struct ntb_transport *nt = qp->transport; 521 struct pci_dev *pdev = ntb_query_pdev(nt->ndev); 522 523 if (qp->qp_link == NTB_LINK_DOWN) { 524 cancel_delayed_work_sync(&qp->link_work); 525 return; 526 } 527 528 if (qp->event_handler) 529 qp->event_handler(qp->cb_data, NTB_LINK_DOWN); 530 531 dev_info(&pdev->dev, "qp %d: Link Down\n", qp->qp_num); 532 qp->qp_link = NTB_LINK_DOWN; 533 534 if (nt->transport_link == NTB_LINK_UP) 535 schedule_delayed_work(&qp->link_work, 536 msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT)); 537 } 538 539 static void ntb_qp_link_down(struct ntb_transport_qp *qp) 540 { 541 schedule_work(&qp->link_cleanup); 542 } 543 544 static void ntb_transport_link_cleanup(struct work_struct *work) 545 { 546 struct ntb_transport *nt = container_of(work, struct ntb_transport, 547 link_cleanup); 548 int i; 549 550 if (nt->transport_link == NTB_LINK_DOWN) 551 cancel_delayed_work_sync(&nt->link_work); 552 else 553 nt->transport_link = NTB_LINK_DOWN; 554 555 /* Pass along the info to any clients */ 556 for (i = 0; i < nt->max_qps; i++) 557 if (!test_bit(i, &nt->qp_bitmap)) 558 ntb_qp_link_down(&nt->qps[i]); 559 560 /* The scratchpad registers keep the values if the remote side 561 * goes down, blast them now to give them a sane value the next 562 * time they are accessed 563 */ 564 for (i = 0; i < MAX_SPAD; i++) 565 ntb_write_local_spad(nt->ndev, i, 0); 566 } 567 568 static void ntb_transport_event_callback(void *data, enum ntb_hw_event event) 569 { 570 struct ntb_transport *nt = data; 571 572 switch (event) { 573 case NTB_EVENT_HW_LINK_UP: 574 schedule_delayed_work(&nt->link_work, 0); 575 break; 576 case NTB_EVENT_HW_LINK_DOWN: 577 schedule_work(&nt->link_cleanup); 578 break; 579 default: 580 BUG(); 581 } 582 } 583 584 static void ntb_transport_link_work(struct work_struct *work) 585 { 586 struct ntb_transport *nt = container_of(work, struct ntb_transport, 587 link_work.work); 588 struct ntb_device *ndev = nt->ndev; 589 struct pci_dev *pdev = ntb_query_pdev(ndev); 590 u32 val; 591 int rc, i; 592 593 /* send the local info */ 594 rc = ntb_write_remote_spad(ndev, VERSION, NTB_TRANSPORT_VERSION); 595 if (rc) { 596 dev_err(&pdev->dev, "Error writing %x to remote spad %d\n", 597 0, VERSION); 598 goto out; 599 } 600 601 rc = ntb_write_remote_spad(ndev, MW0_SZ, ntb_get_mw_size(ndev, 0)); 602 if (rc) { 603 dev_err(&pdev->dev, "Error writing %x to remote spad %d\n", 604 (u32) ntb_get_mw_size(ndev, 0), MW0_SZ); 605 goto out; 606 } 607 608 rc = ntb_write_remote_spad(ndev, MW1_SZ, ntb_get_mw_size(ndev, 1)); 609 if (rc) { 610 dev_err(&pdev->dev, "Error writing %x to remote spad %d\n", 611 (u32) ntb_get_mw_size(ndev, 1), MW1_SZ); 612 goto out; 613 } 614 615 rc = ntb_write_remote_spad(ndev, NUM_QPS, nt->max_qps); 616 if (rc) { 617 dev_err(&pdev->dev, "Error writing %x to remote spad %d\n", 618 nt->max_qps, NUM_QPS); 619 goto out; 620 } 621 622 rc = ntb_read_local_spad(nt->ndev, QP_LINKS, &val); 623 if (rc) { 624 dev_err(&pdev->dev, "Error reading spad %d\n", QP_LINKS); 625 goto out; 626 } 627 628 rc = ntb_write_remote_spad(ndev, QP_LINKS, val); 629 if (rc) { 630 dev_err(&pdev->dev, "Error writing %x to remote spad %d\n", 631 val, QP_LINKS); 632 goto out; 633 } 634 635 /* Query the remote side for its info */ 636 rc = ntb_read_remote_spad(ndev, VERSION, &val); 637 if (rc) { 638 dev_err(&pdev->dev, "Error reading remote spad %d\n", VERSION); 639 goto out; 640 } 641 642 if (val != NTB_TRANSPORT_VERSION) 643 goto out; 644 dev_dbg(&pdev->dev, "Remote version = %d\n", val); 645 646 rc = ntb_read_remote_spad(ndev, NUM_QPS, &val); 647 if (rc) { 648 dev_err(&pdev->dev, "Error reading remote spad %d\n", NUM_QPS); 649 goto out; 650 } 651 652 if (val != nt->max_qps) 653 goto out; 654 dev_dbg(&pdev->dev, "Remote max number of qps = %d\n", val); 655 656 rc = ntb_read_remote_spad(ndev, MW0_SZ, &val); 657 if (rc) { 658 dev_err(&pdev->dev, "Error reading remote spad %d\n", MW0_SZ); 659 goto out; 660 } 661 662 if (!val) 663 goto out; 664 dev_dbg(&pdev->dev, "Remote MW0 size = %d\n", val); 665 666 rc = ntb_set_mw(nt, 0, val); 667 if (rc) 668 goto out; 669 670 rc = ntb_read_remote_spad(ndev, MW1_SZ, &val); 671 if (rc) { 672 dev_err(&pdev->dev, "Error reading remote spad %d\n", MW1_SZ); 673 goto out; 674 } 675 676 if (!val) 677 goto out; 678 dev_dbg(&pdev->dev, "Remote MW1 size = %d\n", val); 679 680 rc = ntb_set_mw(nt, 1, val); 681 if (rc) 682 goto out; 683 684 nt->transport_link = NTB_LINK_UP; 685 686 for (i = 0; i < nt->max_qps; i++) { 687 struct ntb_transport_qp *qp = &nt->qps[i]; 688 689 ntb_transport_setup_qp_mw(nt, i); 690 691 if (qp->client_ready == NTB_LINK_UP) 692 schedule_delayed_work(&qp->link_work, 0); 693 } 694 695 return; 696 697 out: 698 if (ntb_hw_link_status(ndev)) 699 schedule_delayed_work(&nt->link_work, 700 msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT)); 701 } 702 703 static void ntb_qp_link_work(struct work_struct *work) 704 { 705 struct ntb_transport_qp *qp = container_of(work, 706 struct ntb_transport_qp, 707 link_work.work); 708 struct pci_dev *pdev = ntb_query_pdev(qp->ndev); 709 struct ntb_transport *nt = qp->transport; 710 int rc, val; 711 712 WARN_ON(nt->transport_link != NTB_LINK_UP); 713 714 rc = ntb_read_local_spad(nt->ndev, QP_LINKS, &val); 715 if (rc) { 716 dev_err(&pdev->dev, "Error reading spad %d\n", QP_LINKS); 717 return; 718 } 719 720 rc = ntb_write_remote_spad(nt->ndev, QP_LINKS, val | 1 << qp->qp_num); 721 if (rc) 722 dev_err(&pdev->dev, "Error writing %x to remote spad %d\n", 723 val | 1 << qp->qp_num, QP_LINKS); 724 725 /* query remote spad for qp ready bits */ 726 rc = ntb_read_remote_spad(nt->ndev, QP_LINKS, &val); 727 if (rc) 728 dev_err(&pdev->dev, "Error reading remote spad %d\n", QP_LINKS); 729 730 dev_dbg(&pdev->dev, "Remote QP link status = %x\n", val); 731 732 /* See if the remote side is up */ 733 if (1 << qp->qp_num & val) { 734 qp->qp_link = NTB_LINK_UP; 735 736 dev_info(&pdev->dev, "qp %d: Link Up\n", qp->qp_num); 737 if (qp->event_handler) 738 qp->event_handler(qp->cb_data, NTB_LINK_UP); 739 } else if (nt->transport_link == NTB_LINK_UP) 740 schedule_delayed_work(&qp->link_work, 741 msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT)); 742 } 743 744 static void ntb_transport_init_queue(struct ntb_transport *nt, 745 unsigned int qp_num) 746 { 747 struct ntb_transport_qp *qp; 748 unsigned int num_qps_mw, tx_size; 749 u8 mw_num = QP_TO_MW(qp_num); 750 751 qp = &nt->qps[qp_num]; 752 qp->qp_num = qp_num; 753 qp->transport = nt; 754 qp->ndev = nt->ndev; 755 qp->qp_link = NTB_LINK_DOWN; 756 qp->client_ready = NTB_LINK_DOWN; 757 qp->event_handler = NULL; 758 759 if (nt->max_qps % NTB_NUM_MW && mw_num < nt->max_qps % NTB_NUM_MW) 760 num_qps_mw = nt->max_qps / NTB_NUM_MW + 1; 761 else 762 num_qps_mw = nt->max_qps / NTB_NUM_MW; 763 764 tx_size = ntb_get_mw_size(qp->ndev, mw_num) / num_qps_mw; 765 qp->tx_mw_begin = ntb_get_mw_vbase(nt->ndev, mw_num) + 766 (qp_num / NTB_NUM_MW * tx_size); 767 qp->tx_mw_end = qp->tx_mw_begin + tx_size; 768 qp->tx_offset = qp->tx_mw_begin; 769 qp->tx_max_frame = min(transport_mtu, tx_size); 770 771 if (nt->debugfs_dir) { 772 char debugfs_name[4]; 773 774 snprintf(debugfs_name, 4, "qp%d", qp_num); 775 qp->debugfs_dir = debugfs_create_dir(debugfs_name, 776 nt->debugfs_dir); 777 778 qp->debugfs_stats = debugfs_create_file("stats", S_IRUSR, 779 qp->debugfs_dir, qp, 780 &ntb_qp_debugfs_stats); 781 } 782 783 INIT_DELAYED_WORK(&qp->link_work, ntb_qp_link_work); 784 INIT_WORK(&qp->link_cleanup, ntb_qp_link_cleanup); 785 786 spin_lock_init(&qp->ntb_rx_pend_q_lock); 787 spin_lock_init(&qp->ntb_rx_free_q_lock); 788 spin_lock_init(&qp->ntb_tx_free_q_lock); 789 790 INIT_LIST_HEAD(&qp->rx_pend_q); 791 INIT_LIST_HEAD(&qp->rx_free_q); 792 INIT_LIST_HEAD(&qp->tx_free_q); 793 } 794 795 int ntb_transport_init(struct pci_dev *pdev) 796 { 797 struct ntb_transport *nt; 798 int rc, i; 799 800 nt = kzalloc(sizeof(struct ntb_transport), GFP_KERNEL); 801 if (!nt) 802 return -ENOMEM; 803 804 if (debugfs_initialized()) 805 nt->debugfs_dir = debugfs_create_dir(KBUILD_MODNAME, NULL); 806 else 807 nt->debugfs_dir = NULL; 808 809 nt->ndev = ntb_register_transport(pdev, nt); 810 if (!nt->ndev) { 811 rc = -EIO; 812 goto err; 813 } 814 815 nt->max_qps = min(nt->ndev->max_cbs, max_num_clients); 816 817 nt->qps = kcalloc(nt->max_qps, sizeof(struct ntb_transport_qp), 818 GFP_KERNEL); 819 if (!nt->qps) { 820 rc = -ENOMEM; 821 goto err1; 822 } 823 824 nt->qp_bitmap = ((u64) 1 << nt->max_qps) - 1; 825 826 for (i = 0; i < nt->max_qps; i++) 827 ntb_transport_init_queue(nt, i); 828 829 INIT_DELAYED_WORK(&nt->link_work, ntb_transport_link_work); 830 INIT_WORK(&nt->link_cleanup, ntb_transport_link_cleanup); 831 832 rc = ntb_register_event_callback(nt->ndev, 833 ntb_transport_event_callback); 834 if (rc) 835 goto err2; 836 837 INIT_LIST_HEAD(&nt->client_devs); 838 rc = ntb_bus_init(nt); 839 if (rc) 840 goto err3; 841 842 if (ntb_hw_link_status(nt->ndev)) 843 schedule_delayed_work(&nt->link_work, 0); 844 845 return 0; 846 847 err3: 848 ntb_unregister_event_callback(nt->ndev); 849 err2: 850 kfree(nt->qps); 851 err1: 852 ntb_unregister_transport(nt->ndev); 853 err: 854 debugfs_remove_recursive(nt->debugfs_dir); 855 kfree(nt); 856 return rc; 857 } 858 859 void ntb_transport_free(void *transport) 860 { 861 struct ntb_transport *nt = transport; 862 struct pci_dev *pdev; 863 int i; 864 865 nt->transport_link = NTB_LINK_DOWN; 866 867 /* verify that all the qp's are freed */ 868 for (i = 0; i < nt->max_qps; i++) 869 if (!test_bit(i, &nt->qp_bitmap)) 870 ntb_transport_free_queue(&nt->qps[i]); 871 872 ntb_bus_remove(nt); 873 874 cancel_delayed_work_sync(&nt->link_work); 875 876 debugfs_remove_recursive(nt->debugfs_dir); 877 878 ntb_unregister_event_callback(nt->ndev); 879 880 pdev = ntb_query_pdev(nt->ndev); 881 882 for (i = 0; i < NTB_NUM_MW; i++) 883 if (nt->mw[i].virt_addr) 884 dma_free_coherent(&pdev->dev, nt->mw[i].size, 885 nt->mw[i].virt_addr, 886 nt->mw[i].dma_addr); 887 888 kfree(nt->qps); 889 ntb_unregister_transport(nt->ndev); 890 kfree(nt); 891 } 892 893 static void ntb_rx_copy_task(struct ntb_transport_qp *qp, 894 struct ntb_queue_entry *entry, void *offset) 895 { 896 897 struct ntb_payload_header *hdr; 898 899 BUG_ON(offset < qp->rx_buff_begin || 900 offset + qp->rx_max_frame >= qp->rx_buff_end); 901 902 hdr = offset + qp->rx_max_frame - sizeof(struct ntb_payload_header); 903 entry->len = hdr->len; 904 905 memcpy(entry->buf, offset, entry->len); 906 907 /* Ensure that the data is fully copied out before clearing the flag */ 908 wmb(); 909 hdr->flags = 0; 910 911 if (qp->rx_handler && qp->client_ready == NTB_LINK_UP) 912 qp->rx_handler(qp, qp->cb_data, entry->cb_data, entry->len); 913 914 ntb_list_add(&qp->ntb_rx_free_q_lock, &entry->entry, &qp->rx_free_q); 915 } 916 917 static int ntb_process_rxc(struct ntb_transport_qp *qp) 918 { 919 struct ntb_payload_header *hdr; 920 struct ntb_queue_entry *entry; 921 void *offset; 922 923 entry = ntb_list_rm(&qp->ntb_rx_pend_q_lock, &qp->rx_pend_q); 924 if (!entry) { 925 hdr = offset + qp->rx_max_frame - 926 sizeof(struct ntb_payload_header); 927 dev_dbg(&ntb_query_pdev(qp->ndev)->dev, 928 "no buffer - HDR ver %llu, len %d, flags %x\n", 929 hdr->ver, hdr->len, hdr->flags); 930 qp->rx_err_no_buf++; 931 return -ENOMEM; 932 } 933 934 offset = qp->rx_offset; 935 hdr = offset + qp->rx_max_frame - sizeof(struct ntb_payload_header); 936 937 if (!(hdr->flags & DESC_DONE_FLAG)) { 938 ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, 939 &qp->rx_pend_q); 940 qp->rx_ring_empty++; 941 return -EAGAIN; 942 } 943 944 if (hdr->ver != qp->rx_pkts) { 945 dev_dbg(&ntb_query_pdev(qp->ndev)->dev, 946 "qp %d: version mismatch, expected %llu - got %llu\n", 947 qp->qp_num, qp->rx_pkts, hdr->ver); 948 ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, 949 &qp->rx_pend_q); 950 qp->rx_err_ver++; 951 return -EIO; 952 } 953 954 if (hdr->flags & LINK_DOWN_FLAG) { 955 ntb_qp_link_down(qp); 956 957 ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, 958 &qp->rx_pend_q); 959 960 /* Ensure that the data is fully copied out before clearing the 961 * done flag 962 */ 963 wmb(); 964 hdr->flags = 0; 965 goto out; 966 } 967 968 dev_dbg(&ntb_query_pdev(qp->ndev)->dev, 969 "rx offset %p, ver %llu - %d payload received, buf size %d\n", 970 qp->rx_offset, hdr->ver, hdr->len, entry->len); 971 972 if (hdr->len <= entry->len) 973 ntb_rx_copy_task(qp, entry, offset); 974 else { 975 ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, 976 &qp->rx_pend_q); 977 978 /* Ensure that the data is fully copied out before clearing the 979 * done flag 980 */ 981 wmb(); 982 hdr->flags = 0; 983 qp->rx_err_oflow++; 984 dev_dbg(&ntb_query_pdev(qp->ndev)->dev, 985 "RX overflow! Wanted %d got %d\n", 986 hdr->len, entry->len); 987 } 988 989 qp->rx_bytes += hdr->len; 990 qp->rx_pkts++; 991 992 out: 993 qp->rx_offset += qp->rx_max_frame; 994 if (qp->rx_offset + qp->rx_max_frame >= qp->rx_buff_end) 995 qp->rx_offset = qp->rx_buff_begin; 996 997 return 0; 998 } 999 1000 static void ntb_transport_rx(unsigned long data) 1001 { 1002 struct ntb_transport_qp *qp = (struct ntb_transport_qp *)data; 1003 int rc; 1004 1005 do { 1006 rc = ntb_process_rxc(qp); 1007 } while (!rc); 1008 } 1009 1010 static void ntb_transport_rxc_db(void *data, int db_num) 1011 { 1012 struct ntb_transport_qp *qp = data; 1013 1014 dev_dbg(&ntb_query_pdev(qp->ndev)->dev, "%s: doorbell %d received\n", 1015 __func__, db_num); 1016 1017 tasklet_schedule(&qp->rx_work); 1018 } 1019 1020 static void ntb_tx_copy_task(struct ntb_transport_qp *qp, 1021 struct ntb_queue_entry *entry, 1022 void *offset) 1023 { 1024 struct ntb_payload_header *hdr; 1025 1026 BUG_ON(offset < qp->tx_mw_begin || 1027 offset + qp->tx_max_frame >= qp->tx_mw_end); 1028 1029 memcpy_toio(offset, entry->buf, entry->len); 1030 1031 hdr = offset + qp->tx_max_frame - sizeof(struct ntb_payload_header); 1032 hdr->len = entry->len; 1033 hdr->ver = qp->tx_pkts; 1034 1035 /* Ensure that the data is fully copied out before setting the flag */ 1036 wmb(); 1037 hdr->flags = entry->flags | DESC_DONE_FLAG; 1038 1039 ntb_ring_sdb(qp->ndev, qp->qp_num); 1040 1041 /* The entry length can only be zero if the packet is intended to be a 1042 * "link down" or similar. Since no payload is being sent in these 1043 * cases, there is nothing to add to the completion queue. 1044 */ 1045 if (entry->len > 0) { 1046 qp->tx_bytes += entry->len; 1047 1048 if (qp->tx_handler) 1049 qp->tx_handler(qp, qp->cb_data, entry->cb_data, 1050 entry->len); 1051 } 1052 1053 ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, &qp->tx_free_q); 1054 } 1055 1056 static int ntb_process_tx(struct ntb_transport_qp *qp, 1057 struct ntb_queue_entry *entry) 1058 { 1059 struct ntb_payload_header *hdr; 1060 void *offset; 1061 1062 offset = qp->tx_offset; 1063 hdr = offset + qp->tx_max_frame - sizeof(struct ntb_payload_header); 1064 1065 dev_dbg(&ntb_query_pdev(qp->ndev)->dev, "%lld - offset %p, tx %p, entry len %d flags %x buff %p\n", 1066 qp->tx_pkts, offset, qp->tx_offset, entry->len, entry->flags, 1067 entry->buf); 1068 if (hdr->flags) { 1069 qp->tx_ring_full++; 1070 return -EAGAIN; 1071 } 1072 1073 if (entry->len > qp->tx_max_frame - sizeof(struct ntb_payload_header)) { 1074 if (qp->tx_handler) 1075 qp->tx_handler(qp->cb_data, qp, NULL, -EIO); 1076 1077 ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, 1078 &qp->tx_free_q); 1079 return 0; 1080 } 1081 1082 ntb_tx_copy_task(qp, entry, offset); 1083 1084 qp->tx_offset += qp->tx_max_frame; 1085 if (qp->tx_offset + qp->tx_max_frame >= qp->tx_mw_end) 1086 qp->tx_offset = qp->tx_mw_begin; 1087 1088 qp->tx_pkts++; 1089 1090 return 0; 1091 } 1092 1093 static void ntb_send_link_down(struct ntb_transport_qp *qp) 1094 { 1095 struct pci_dev *pdev = ntb_query_pdev(qp->ndev); 1096 struct ntb_queue_entry *entry; 1097 int i, rc; 1098 1099 if (qp->qp_link == NTB_LINK_DOWN) 1100 return; 1101 1102 qp->qp_link = NTB_LINK_DOWN; 1103 dev_info(&pdev->dev, "qp %d: Link Down\n", qp->qp_num); 1104 1105 for (i = 0; i < NTB_LINK_DOWN_TIMEOUT; i++) { 1106 entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, 1107 &qp->tx_free_q); 1108 if (entry) 1109 break; 1110 msleep(100); 1111 } 1112 1113 if (!entry) 1114 return; 1115 1116 entry->cb_data = NULL; 1117 entry->buf = NULL; 1118 entry->len = 0; 1119 entry->flags = LINK_DOWN_FLAG; 1120 1121 rc = ntb_process_tx(qp, entry); 1122 if (rc) 1123 dev_err(&pdev->dev, "ntb: QP%d unable to send linkdown msg\n", 1124 qp->qp_num); 1125 } 1126 1127 /** 1128 * ntb_transport_create_queue - Create a new NTB transport layer queue 1129 * @rx_handler: receive callback function 1130 * @tx_handler: transmit callback function 1131 * @event_handler: event callback function 1132 * 1133 * Create a new NTB transport layer queue and provide the queue with a callback 1134 * routine for both transmit and receive. The receive callback routine will be 1135 * used to pass up data when the transport has received it on the queue. The 1136 * transmit callback routine will be called when the transport has completed the 1137 * transmission of the data on the queue and the data is ready to be freed. 1138 * 1139 * RETURNS: pointer to newly created ntb_queue, NULL on error. 1140 */ 1141 struct ntb_transport_qp * 1142 ntb_transport_create_queue(void *data, struct pci_dev *pdev, 1143 const struct ntb_queue_handlers *handlers) 1144 { 1145 struct ntb_queue_entry *entry; 1146 struct ntb_transport_qp *qp; 1147 struct ntb_transport *nt; 1148 unsigned int free_queue; 1149 int rc, i; 1150 1151 nt = ntb_find_transport(pdev); 1152 if (!nt) 1153 goto err; 1154 1155 free_queue = ffs(nt->qp_bitmap); 1156 if (!free_queue) 1157 goto err; 1158 1159 /* decrement free_queue to make it zero based */ 1160 free_queue--; 1161 1162 clear_bit(free_queue, &nt->qp_bitmap); 1163 1164 qp = &nt->qps[free_queue]; 1165 qp->cb_data = data; 1166 qp->rx_handler = handlers->rx_handler; 1167 qp->tx_handler = handlers->tx_handler; 1168 qp->event_handler = handlers->event_handler; 1169 1170 for (i = 0; i < NTB_QP_DEF_NUM_ENTRIES; i++) { 1171 entry = kzalloc(sizeof(struct ntb_queue_entry), GFP_ATOMIC); 1172 if (!entry) 1173 goto err1; 1174 1175 ntb_list_add(&qp->ntb_rx_free_q_lock, &entry->entry, 1176 &qp->rx_free_q); 1177 } 1178 1179 for (i = 0; i < NTB_QP_DEF_NUM_ENTRIES; i++) { 1180 entry = kzalloc(sizeof(struct ntb_queue_entry), GFP_ATOMIC); 1181 if (!entry) 1182 goto err2; 1183 1184 ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, 1185 &qp->tx_free_q); 1186 } 1187 1188 tasklet_init(&qp->rx_work, ntb_transport_rx, (unsigned long) qp); 1189 1190 rc = ntb_register_db_callback(qp->ndev, free_queue, qp, 1191 ntb_transport_rxc_db); 1192 if (rc) 1193 goto err3; 1194 1195 dev_info(&pdev->dev, "NTB Transport QP %d created\n", qp->qp_num); 1196 1197 return qp; 1198 1199 err3: 1200 tasklet_disable(&qp->rx_work); 1201 err2: 1202 while ((entry = 1203 ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q))) 1204 kfree(entry); 1205 err1: 1206 while ((entry = 1207 ntb_list_rm(&qp->ntb_rx_free_q_lock, &qp->rx_free_q))) 1208 kfree(entry); 1209 set_bit(free_queue, &nt->qp_bitmap); 1210 err: 1211 return NULL; 1212 } 1213 EXPORT_SYMBOL_GPL(ntb_transport_create_queue); 1214 1215 /** 1216 * ntb_transport_free_queue - Frees NTB transport queue 1217 * @qp: NTB queue to be freed 1218 * 1219 * Frees NTB transport queue 1220 */ 1221 void ntb_transport_free_queue(struct ntb_transport_qp *qp) 1222 { 1223 struct pci_dev *pdev = ntb_query_pdev(qp->ndev); 1224 struct ntb_queue_entry *entry; 1225 1226 if (!qp) 1227 return; 1228 1229 cancel_delayed_work_sync(&qp->link_work); 1230 1231 ntb_unregister_db_callback(qp->ndev, qp->qp_num); 1232 tasklet_disable(&qp->rx_work); 1233 1234 while ((entry = 1235 ntb_list_rm(&qp->ntb_rx_free_q_lock, &qp->rx_free_q))) 1236 kfree(entry); 1237 1238 while ((entry = 1239 ntb_list_rm(&qp->ntb_rx_pend_q_lock, &qp->rx_pend_q))) { 1240 dev_warn(&pdev->dev, "Freeing item from a non-empty queue\n"); 1241 kfree(entry); 1242 } 1243 1244 while ((entry = 1245 ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q))) 1246 kfree(entry); 1247 1248 set_bit(qp->qp_num, &qp->transport->qp_bitmap); 1249 1250 dev_info(&pdev->dev, "NTB Transport QP %d freed\n", qp->qp_num); 1251 } 1252 EXPORT_SYMBOL_GPL(ntb_transport_free_queue); 1253 1254 /** 1255 * ntb_transport_rx_remove - Dequeues enqueued rx packet 1256 * @qp: NTB queue to be freed 1257 * @len: pointer to variable to write enqueued buffers length 1258 * 1259 * Dequeues unused buffers from receive queue. Should only be used during 1260 * shutdown of qp. 1261 * 1262 * RETURNS: NULL error value on error, or void* for success. 1263 */ 1264 void *ntb_transport_rx_remove(struct ntb_transport_qp *qp, unsigned int *len) 1265 { 1266 struct ntb_queue_entry *entry; 1267 void *buf; 1268 1269 if (!qp || qp->client_ready == NTB_LINK_UP) 1270 return NULL; 1271 1272 entry = ntb_list_rm(&qp->ntb_rx_pend_q_lock, &qp->rx_pend_q); 1273 if (!entry) 1274 return NULL; 1275 1276 buf = entry->cb_data; 1277 *len = entry->len; 1278 1279 ntb_list_add(&qp->ntb_rx_free_q_lock, &entry->entry, 1280 &qp->rx_free_q); 1281 1282 return buf; 1283 } 1284 EXPORT_SYMBOL_GPL(ntb_transport_rx_remove); 1285 1286 /** 1287 * ntb_transport_rx_enqueue - Enqueue a new NTB queue entry 1288 * @qp: NTB transport layer queue the entry is to be enqueued on 1289 * @cb: per buffer pointer for callback function to use 1290 * @data: pointer to data buffer that incoming packets will be copied into 1291 * @len: length of the data buffer 1292 * 1293 * Enqueue a new receive buffer onto the transport queue into which a NTB 1294 * payload can be received into. 1295 * 1296 * RETURNS: An appropriate -ERRNO error value on error, or zero for success. 1297 */ 1298 int ntb_transport_rx_enqueue(struct ntb_transport_qp *qp, void *cb, void *data, 1299 unsigned int len) 1300 { 1301 struct ntb_queue_entry *entry; 1302 1303 if (!qp) 1304 return -EINVAL; 1305 1306 entry = ntb_list_rm(&qp->ntb_rx_free_q_lock, &qp->rx_free_q); 1307 if (!entry) 1308 return -ENOMEM; 1309 1310 entry->cb_data = cb; 1311 entry->buf = data; 1312 entry->len = len; 1313 1314 ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, 1315 &qp->rx_pend_q); 1316 1317 return 0; 1318 } 1319 EXPORT_SYMBOL_GPL(ntb_transport_rx_enqueue); 1320 1321 /** 1322 * ntb_transport_tx_enqueue - Enqueue a new NTB queue entry 1323 * @qp: NTB transport layer queue the entry is to be enqueued on 1324 * @cb: per buffer pointer for callback function to use 1325 * @data: pointer to data buffer that will be sent 1326 * @len: length of the data buffer 1327 * 1328 * Enqueue a new transmit buffer onto the transport queue from which a NTB 1329 * payload will be transmitted. This assumes that a lock is behing held to 1330 * serialize access to the qp. 1331 * 1332 * RETURNS: An appropriate -ERRNO error value on error, or zero for success. 1333 */ 1334 int ntb_transport_tx_enqueue(struct ntb_transport_qp *qp, void *cb, void *data, 1335 unsigned int len) 1336 { 1337 struct ntb_queue_entry *entry; 1338 int rc; 1339 1340 if (!qp || qp->qp_link != NTB_LINK_UP || !len) 1341 return -EINVAL; 1342 1343 entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q); 1344 if (!entry) 1345 return -ENOMEM; 1346 1347 entry->cb_data = cb; 1348 entry->buf = data; 1349 entry->len = len; 1350 entry->flags = 0; 1351 1352 rc = ntb_process_tx(qp, entry); 1353 if (rc) 1354 ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, 1355 &qp->tx_free_q); 1356 1357 return rc; 1358 } 1359 EXPORT_SYMBOL_GPL(ntb_transport_tx_enqueue); 1360 1361 /** 1362 * ntb_transport_link_up - Notify NTB transport of client readiness to use queue 1363 * @qp: NTB transport layer queue to be enabled 1364 * 1365 * Notify NTB transport layer of client readiness to use queue 1366 */ 1367 void ntb_transport_link_up(struct ntb_transport_qp *qp) 1368 { 1369 if (!qp) 1370 return; 1371 1372 qp->client_ready = NTB_LINK_UP; 1373 1374 if (qp->transport->transport_link == NTB_LINK_UP) 1375 schedule_delayed_work(&qp->link_work, 0); 1376 } 1377 EXPORT_SYMBOL_GPL(ntb_transport_link_up); 1378 1379 /** 1380 * ntb_transport_link_down - Notify NTB transport to no longer enqueue data 1381 * @qp: NTB transport layer queue to be disabled 1382 * 1383 * Notify NTB transport layer of client's desire to no longer receive data on 1384 * transport queue specified. It is the client's responsibility to ensure all 1385 * entries on queue are purged or otherwise handled appropraitely. 1386 */ 1387 void ntb_transport_link_down(struct ntb_transport_qp *qp) 1388 { 1389 struct pci_dev *pdev = ntb_query_pdev(qp->ndev); 1390 int rc, val; 1391 1392 if (!qp) 1393 return; 1394 1395 qp->client_ready = NTB_LINK_DOWN; 1396 1397 rc = ntb_read_local_spad(qp->ndev, QP_LINKS, &val); 1398 if (rc) { 1399 dev_err(&pdev->dev, "Error reading spad %d\n", QP_LINKS); 1400 return; 1401 } 1402 1403 rc = ntb_write_remote_spad(qp->ndev, QP_LINKS, 1404 val & ~(1 << qp->qp_num)); 1405 if (rc) 1406 dev_err(&pdev->dev, "Error writing %x to remote spad %d\n", 1407 val & ~(1 << qp->qp_num), QP_LINKS); 1408 1409 if (qp->qp_link == NTB_LINK_UP) 1410 ntb_send_link_down(qp); 1411 else 1412 cancel_delayed_work_sync(&qp->link_work); 1413 } 1414 EXPORT_SYMBOL_GPL(ntb_transport_link_down); 1415 1416 /** 1417 * ntb_transport_link_query - Query transport link state 1418 * @qp: NTB transport layer queue to be queried 1419 * 1420 * Query connectivity to the remote system of the NTB transport queue 1421 * 1422 * RETURNS: true for link up or false for link down 1423 */ 1424 bool ntb_transport_link_query(struct ntb_transport_qp *qp) 1425 { 1426 return qp->qp_link == NTB_LINK_UP; 1427 } 1428 EXPORT_SYMBOL_GPL(ntb_transport_link_query); 1429 1430 /** 1431 * ntb_transport_qp_num - Query the qp number 1432 * @qp: NTB transport layer queue to be queried 1433 * 1434 * Query qp number of the NTB transport queue 1435 * 1436 * RETURNS: a zero based number specifying the qp number 1437 */ 1438 unsigned char ntb_transport_qp_num(struct ntb_transport_qp *qp) 1439 { 1440 return qp->qp_num; 1441 } 1442 EXPORT_SYMBOL_GPL(ntb_transport_qp_num); 1443 1444 /** 1445 * ntb_transport_max_size - Query the max payload size of a qp 1446 * @qp: NTB transport layer queue to be queried 1447 * 1448 * Query the maximum payload size permissible on the given qp 1449 * 1450 * RETURNS: the max payload size of a qp 1451 */ 1452 unsigned int ntb_transport_max_size(struct ntb_transport_qp *qp) 1453 { 1454 return qp->tx_max_frame - sizeof(struct ntb_payload_header); 1455 } 1456 EXPORT_SYMBOL_GPL(ntb_transport_max_size); 1457