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 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 = 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_rx_info { 82 unsigned int entry; 83 }; 84 85 struct ntb_transport_qp { 86 struct ntb_transport *transport; 87 struct ntb_device *ndev; 88 void *cb_data; 89 90 bool client_ready; 91 bool qp_link; 92 u8 qp_num; /* Only 64 QP's are allowed. 0-63 */ 93 94 struct ntb_rx_info __iomem *rx_info; 95 struct ntb_rx_info *remote_rx_info; 96 97 void (*tx_handler) (struct ntb_transport_qp *qp, void *qp_data, 98 void *data, int len); 99 struct list_head tx_free_q; 100 spinlock_t ntb_tx_free_q_lock; 101 void __iomem *tx_mw; 102 unsigned int tx_index; 103 unsigned int tx_max_entry; 104 unsigned int tx_max_frame; 105 106 void (*rx_handler) (struct ntb_transport_qp *qp, void *qp_data, 107 void *data, int len); 108 struct tasklet_struct rx_work; 109 struct list_head rx_pend_q; 110 struct list_head rx_free_q; 111 spinlock_t ntb_rx_pend_q_lock; 112 spinlock_t ntb_rx_free_q_lock; 113 void *rx_buff; 114 unsigned int rx_index; 115 unsigned int rx_max_entry; 116 unsigned int rx_max_frame; 117 118 void (*event_handler) (void *data, int status); 119 struct delayed_work link_work; 120 struct work_struct link_cleanup; 121 122 struct dentry *debugfs_dir; 123 struct dentry *debugfs_stats; 124 125 /* Stats */ 126 u64 rx_bytes; 127 u64 rx_pkts; 128 u64 rx_ring_empty; 129 u64 rx_err_no_buf; 130 u64 rx_err_oflow; 131 u64 rx_err_ver; 132 u64 tx_bytes; 133 u64 tx_pkts; 134 u64 tx_ring_full; 135 }; 136 137 struct ntb_transport_mw { 138 size_t size; 139 void *virt_addr; 140 dma_addr_t dma_addr; 141 }; 142 143 struct ntb_transport_client_dev { 144 struct list_head entry; 145 struct device dev; 146 }; 147 148 struct ntb_transport { 149 struct list_head entry; 150 struct list_head client_devs; 151 152 struct ntb_device *ndev; 153 struct ntb_transport_mw mw[NTB_NUM_MW]; 154 struct ntb_transport_qp *qps; 155 unsigned int max_qps; 156 unsigned long qp_bitmap; 157 bool transport_link; 158 struct delayed_work link_work; 159 struct work_struct link_cleanup; 160 }; 161 162 enum { 163 DESC_DONE_FLAG = 1 << 0, 164 LINK_DOWN_FLAG = 1 << 1, 165 }; 166 167 struct ntb_payload_header { 168 unsigned int ver; 169 unsigned int len; 170 unsigned int flags; 171 }; 172 173 enum { 174 VERSION = 0, 175 QP_LINKS, 176 NUM_QPS, 177 NUM_MWS, 178 MW0_SZ_HIGH, 179 MW0_SZ_LOW, 180 MW1_SZ_HIGH, 181 MW1_SZ_LOW, 182 MAX_SPAD, 183 }; 184 185 #define QP_TO_MW(qp) ((qp) % NTB_NUM_MW) 186 #define NTB_QP_DEF_NUM_ENTRIES 100 187 #define NTB_LINK_DOWN_TIMEOUT 10 188 189 static int ntb_match_bus(struct device *dev, struct device_driver *drv) 190 { 191 return !strncmp(dev_name(dev), drv->name, strlen(drv->name)); 192 } 193 194 static int ntb_client_probe(struct device *dev) 195 { 196 const struct ntb_client *drv = container_of(dev->driver, 197 struct ntb_client, driver); 198 struct pci_dev *pdev = container_of(dev->parent, struct pci_dev, dev); 199 int rc = -EINVAL; 200 201 get_device(dev); 202 if (drv && drv->probe) 203 rc = drv->probe(pdev); 204 if (rc) 205 put_device(dev); 206 207 return rc; 208 } 209 210 static int ntb_client_remove(struct device *dev) 211 { 212 const struct ntb_client *drv = container_of(dev->driver, 213 struct ntb_client, driver); 214 struct pci_dev *pdev = container_of(dev->parent, struct pci_dev, dev); 215 216 if (drv && drv->remove) 217 drv->remove(pdev); 218 219 put_device(dev); 220 221 return 0; 222 } 223 224 static struct bus_type ntb_bus_type = { 225 .name = "ntb_bus", 226 .match = ntb_match_bus, 227 .probe = ntb_client_probe, 228 .remove = ntb_client_remove, 229 }; 230 231 static LIST_HEAD(ntb_transport_list); 232 233 static int ntb_bus_init(struct ntb_transport *nt) 234 { 235 if (list_empty(&ntb_transport_list)) { 236 int rc = bus_register(&ntb_bus_type); 237 if (rc) 238 return rc; 239 } 240 241 list_add(&nt->entry, &ntb_transport_list); 242 243 return 0; 244 } 245 246 static void ntb_bus_remove(struct ntb_transport *nt) 247 { 248 struct ntb_transport_client_dev *client_dev, *cd; 249 250 list_for_each_entry_safe(client_dev, cd, &nt->client_devs, entry) { 251 dev_err(client_dev->dev.parent, "%s still attached to bus, removing\n", 252 dev_name(&client_dev->dev)); 253 list_del(&client_dev->entry); 254 device_unregister(&client_dev->dev); 255 } 256 257 list_del(&nt->entry); 258 259 if (list_empty(&ntb_transport_list)) 260 bus_unregister(&ntb_bus_type); 261 } 262 263 static void ntb_client_release(struct device *dev) 264 { 265 struct ntb_transport_client_dev *client_dev; 266 client_dev = container_of(dev, struct ntb_transport_client_dev, dev); 267 268 kfree(client_dev); 269 } 270 271 /** 272 * ntb_unregister_client_dev - Unregister NTB client device 273 * @device_name: Name of NTB client device 274 * 275 * Unregister an NTB client device with the NTB transport layer 276 */ 277 void ntb_unregister_client_dev(char *device_name) 278 { 279 struct ntb_transport_client_dev *client, *cd; 280 struct ntb_transport *nt; 281 282 list_for_each_entry(nt, &ntb_transport_list, entry) 283 list_for_each_entry_safe(client, cd, &nt->client_devs, entry) 284 if (!strncmp(dev_name(&client->dev), device_name, 285 strlen(device_name))) { 286 list_del(&client->entry); 287 device_unregister(&client->dev); 288 } 289 } 290 EXPORT_SYMBOL_GPL(ntb_unregister_client_dev); 291 292 /** 293 * ntb_register_client_dev - Register NTB client device 294 * @device_name: Name of NTB client device 295 * 296 * Register an NTB client device with the NTB transport layer 297 */ 298 int ntb_register_client_dev(char *device_name) 299 { 300 struct ntb_transport_client_dev *client_dev; 301 struct ntb_transport *nt; 302 int rc, i = 0; 303 304 if (list_empty(&ntb_transport_list)) 305 return -ENODEV; 306 307 list_for_each_entry(nt, &ntb_transport_list, entry) { 308 struct device *dev; 309 310 client_dev = kzalloc(sizeof(struct ntb_transport_client_dev), 311 GFP_KERNEL); 312 if (!client_dev) { 313 rc = -ENOMEM; 314 goto err; 315 } 316 317 dev = &client_dev->dev; 318 319 /* setup and register client devices */ 320 dev_set_name(dev, "%s%d", device_name, i); 321 dev->bus = &ntb_bus_type; 322 dev->release = ntb_client_release; 323 dev->parent = &ntb_query_pdev(nt->ndev)->dev; 324 325 rc = device_register(dev); 326 if (rc) { 327 kfree(client_dev); 328 goto err; 329 } 330 331 list_add_tail(&client_dev->entry, &nt->client_devs); 332 i++; 333 } 334 335 return 0; 336 337 err: 338 ntb_unregister_client_dev(device_name); 339 340 return rc; 341 } 342 EXPORT_SYMBOL_GPL(ntb_register_client_dev); 343 344 /** 345 * ntb_register_client - Register NTB client driver 346 * @drv: NTB client driver to be registered 347 * 348 * Register an NTB client driver with the NTB transport layer 349 * 350 * RETURNS: An appropriate -ERRNO error value on error, or zero for success. 351 */ 352 int ntb_register_client(struct ntb_client *drv) 353 { 354 drv->driver.bus = &ntb_bus_type; 355 356 if (list_empty(&ntb_transport_list)) 357 return -ENODEV; 358 359 return driver_register(&drv->driver); 360 } 361 EXPORT_SYMBOL_GPL(ntb_register_client); 362 363 /** 364 * ntb_unregister_client - Unregister NTB client driver 365 * @drv: NTB client driver to be unregistered 366 * 367 * Unregister an NTB client driver with the NTB transport layer 368 * 369 * RETURNS: An appropriate -ERRNO error value on error, or zero for success. 370 */ 371 void ntb_unregister_client(struct ntb_client *drv) 372 { 373 driver_unregister(&drv->driver); 374 } 375 EXPORT_SYMBOL_GPL(ntb_unregister_client); 376 377 static ssize_t debugfs_read(struct file *filp, char __user *ubuf, size_t count, 378 loff_t *offp) 379 { 380 struct ntb_transport_qp *qp; 381 char *buf; 382 ssize_t ret, out_offset, out_count; 383 384 out_count = 600; 385 386 buf = kmalloc(out_count, GFP_KERNEL); 387 if (!buf) 388 return -ENOMEM; 389 390 qp = filp->private_data; 391 out_offset = 0; 392 out_offset += snprintf(buf + out_offset, out_count - out_offset, 393 "NTB QP stats\n"); 394 out_offset += snprintf(buf + out_offset, out_count - out_offset, 395 "rx_bytes - \t%llu\n", qp->rx_bytes); 396 out_offset += snprintf(buf + out_offset, out_count - out_offset, 397 "rx_pkts - \t%llu\n", qp->rx_pkts); 398 out_offset += snprintf(buf + out_offset, out_count - out_offset, 399 "rx_ring_empty - %llu\n", qp->rx_ring_empty); 400 out_offset += snprintf(buf + out_offset, out_count - out_offset, 401 "rx_err_no_buf - %llu\n", qp->rx_err_no_buf); 402 out_offset += snprintf(buf + out_offset, out_count - out_offset, 403 "rx_err_oflow - \t%llu\n", qp->rx_err_oflow); 404 out_offset += snprintf(buf + out_offset, out_count - out_offset, 405 "rx_err_ver - \t%llu\n", qp->rx_err_ver); 406 out_offset += snprintf(buf + out_offset, out_count - out_offset, 407 "rx_buff - \t%p\n", qp->rx_buff); 408 out_offset += snprintf(buf + out_offset, out_count - out_offset, 409 "rx_index - \t%u\n", qp->rx_index); 410 out_offset += snprintf(buf + out_offset, out_count - out_offset, 411 "rx_max_entry - \t%u\n", qp->rx_max_entry); 412 413 out_offset += snprintf(buf + out_offset, out_count - out_offset, 414 "tx_bytes - \t%llu\n", qp->tx_bytes); 415 out_offset += snprintf(buf + out_offset, out_count - out_offset, 416 "tx_pkts - \t%llu\n", qp->tx_pkts); 417 out_offset += snprintf(buf + out_offset, out_count - out_offset, 418 "tx_ring_full - \t%llu\n", qp->tx_ring_full); 419 out_offset += snprintf(buf + out_offset, out_count - out_offset, 420 "tx_mw - \t%p\n", qp->tx_mw); 421 out_offset += snprintf(buf + out_offset, out_count - out_offset, 422 "tx_index - \t%u\n", qp->tx_index); 423 out_offset += snprintf(buf + out_offset, out_count - out_offset, 424 "tx_max_entry - \t%u\n", qp->tx_max_entry); 425 426 out_offset += snprintf(buf + out_offset, out_count - out_offset, 427 "\nQP Link %s\n", (qp->qp_link == NTB_LINK_UP) ? 428 "Up" : "Down"); 429 if (out_offset > out_count) 430 out_offset = out_count; 431 432 ret = simple_read_from_buffer(ubuf, count, offp, buf, out_offset); 433 kfree(buf); 434 return ret; 435 } 436 437 static const struct file_operations ntb_qp_debugfs_stats = { 438 .owner = THIS_MODULE, 439 .open = simple_open, 440 .read = debugfs_read, 441 }; 442 443 static void ntb_list_add(spinlock_t *lock, struct list_head *entry, 444 struct list_head *list) 445 { 446 unsigned long flags; 447 448 spin_lock_irqsave(lock, flags); 449 list_add_tail(entry, list); 450 spin_unlock_irqrestore(lock, flags); 451 } 452 453 static struct ntb_queue_entry *ntb_list_rm(spinlock_t *lock, 454 struct list_head *list) 455 { 456 struct ntb_queue_entry *entry; 457 unsigned long flags; 458 459 spin_lock_irqsave(lock, flags); 460 if (list_empty(list)) { 461 entry = NULL; 462 goto out; 463 } 464 entry = list_first_entry(list, struct ntb_queue_entry, entry); 465 list_del(&entry->entry); 466 out: 467 spin_unlock_irqrestore(lock, flags); 468 469 return entry; 470 } 471 472 static void ntb_transport_setup_qp_mw(struct ntb_transport *nt, 473 unsigned int qp_num) 474 { 475 struct ntb_transport_qp *qp = &nt->qps[qp_num]; 476 unsigned int rx_size, num_qps_mw; 477 u8 mw_num = QP_TO_MW(qp_num); 478 unsigned int i; 479 480 WARN_ON(nt->mw[mw_num].virt_addr == NULL); 481 482 if (nt->max_qps % NTB_NUM_MW && mw_num < nt->max_qps % NTB_NUM_MW) 483 num_qps_mw = nt->max_qps / NTB_NUM_MW + 1; 484 else 485 num_qps_mw = nt->max_qps / NTB_NUM_MW; 486 487 rx_size = (unsigned int) nt->mw[mw_num].size / num_qps_mw; 488 qp->remote_rx_info = nt->mw[mw_num].virt_addr + 489 (qp_num / NTB_NUM_MW * rx_size); 490 rx_size -= sizeof(struct ntb_rx_info); 491 492 qp->rx_buff = qp->remote_rx_info + 1; 493 /* Due to housekeeping, there must be atleast 2 buffs */ 494 qp->rx_max_frame = min(transport_mtu, rx_size / 2); 495 qp->rx_max_entry = rx_size / qp->rx_max_frame; 496 qp->rx_index = 0; 497 498 qp->remote_rx_info->entry = qp->rx_max_entry - 1; 499 500 /* setup the hdr offsets with 0's */ 501 for (i = 0; i < qp->rx_max_entry; i++) { 502 void *offset = qp->rx_buff + qp->rx_max_frame * (i + 1) - 503 sizeof(struct ntb_payload_header); 504 memset(offset, 0, sizeof(struct ntb_payload_header)); 505 } 506 507 qp->rx_pkts = 0; 508 qp->tx_pkts = 0; 509 qp->tx_index = 0; 510 } 511 512 static void ntb_free_mw(struct ntb_transport *nt, int num_mw) 513 { 514 struct ntb_transport_mw *mw = &nt->mw[num_mw]; 515 struct pci_dev *pdev = ntb_query_pdev(nt->ndev); 516 517 if (!mw->virt_addr) 518 return; 519 520 dma_free_coherent(&pdev->dev, mw->size, mw->virt_addr, mw->dma_addr); 521 mw->virt_addr = NULL; 522 } 523 524 static int ntb_set_mw(struct ntb_transport *nt, int num_mw, unsigned int size) 525 { 526 struct ntb_transport_mw *mw = &nt->mw[num_mw]; 527 struct pci_dev *pdev = ntb_query_pdev(nt->ndev); 528 529 /* No need to re-setup */ 530 if (mw->size == ALIGN(size, 4096)) 531 return 0; 532 533 if (mw->size != 0) 534 ntb_free_mw(nt, num_mw); 535 536 /* Alloc memory for receiving data. Must be 4k aligned */ 537 mw->size = ALIGN(size, 4096); 538 539 mw->virt_addr = dma_alloc_coherent(&pdev->dev, mw->size, &mw->dma_addr, 540 GFP_KERNEL); 541 if (!mw->virt_addr) { 542 mw->size = 0; 543 dev_err(&pdev->dev, "Unable to allocate MW buffer of size %d\n", 544 (int) mw->size); 545 return -ENOMEM; 546 } 547 548 /* Notify HW the memory location of the receive buffer */ 549 ntb_set_mw_addr(nt->ndev, num_mw, mw->dma_addr); 550 551 return 0; 552 } 553 554 static void ntb_qp_link_cleanup(struct work_struct *work) 555 { 556 struct ntb_transport_qp *qp = container_of(work, 557 struct ntb_transport_qp, 558 link_cleanup); 559 struct ntb_transport *nt = qp->transport; 560 struct pci_dev *pdev = ntb_query_pdev(nt->ndev); 561 562 if (qp->qp_link == NTB_LINK_DOWN) { 563 cancel_delayed_work_sync(&qp->link_work); 564 return; 565 } 566 567 if (qp->event_handler) 568 qp->event_handler(qp->cb_data, NTB_LINK_DOWN); 569 570 dev_info(&pdev->dev, "qp %d: Link Down\n", qp->qp_num); 571 qp->qp_link = NTB_LINK_DOWN; 572 573 if (nt->transport_link == NTB_LINK_UP) 574 schedule_delayed_work(&qp->link_work, 575 msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT)); 576 } 577 578 static void ntb_qp_link_down(struct ntb_transport_qp *qp) 579 { 580 schedule_work(&qp->link_cleanup); 581 } 582 583 static void ntb_transport_link_cleanup(struct work_struct *work) 584 { 585 struct ntb_transport *nt = container_of(work, struct ntb_transport, 586 link_cleanup); 587 int i; 588 589 if (nt->transport_link == NTB_LINK_DOWN) 590 cancel_delayed_work_sync(&nt->link_work); 591 else 592 nt->transport_link = NTB_LINK_DOWN; 593 594 /* Pass along the info to any clients */ 595 for (i = 0; i < nt->max_qps; i++) 596 if (!test_bit(i, &nt->qp_bitmap)) 597 ntb_qp_link_down(&nt->qps[i]); 598 599 /* The scratchpad registers keep the values if the remote side 600 * goes down, blast them now to give them a sane value the next 601 * time they are accessed 602 */ 603 for (i = 0; i < MAX_SPAD; i++) 604 ntb_write_local_spad(nt->ndev, i, 0); 605 } 606 607 static void ntb_transport_event_callback(void *data, enum ntb_hw_event event) 608 { 609 struct ntb_transport *nt = data; 610 611 switch (event) { 612 case NTB_EVENT_HW_LINK_UP: 613 schedule_delayed_work(&nt->link_work, 0); 614 break; 615 case NTB_EVENT_HW_LINK_DOWN: 616 schedule_work(&nt->link_cleanup); 617 break; 618 default: 619 BUG(); 620 } 621 } 622 623 static void ntb_transport_link_work(struct work_struct *work) 624 { 625 struct ntb_transport *nt = container_of(work, struct ntb_transport, 626 link_work.work); 627 struct ntb_device *ndev = nt->ndev; 628 struct pci_dev *pdev = ntb_query_pdev(ndev); 629 u32 val; 630 int rc, i; 631 632 /* send the local info, in the opposite order of the way we read it */ 633 for (i = 0; i < NTB_NUM_MW; i++) { 634 rc = ntb_write_remote_spad(ndev, MW0_SZ_HIGH + (i * 2), 635 ntb_get_mw_size(ndev, i) >> 32); 636 if (rc) { 637 dev_err(&pdev->dev, "Error writing %u to remote spad %d\n", 638 (u32)(ntb_get_mw_size(ndev, i) >> 32), 639 MW0_SZ_HIGH + (i * 2)); 640 goto out; 641 } 642 643 rc = ntb_write_remote_spad(ndev, MW0_SZ_LOW + (i * 2), 644 (u32) ntb_get_mw_size(ndev, i)); 645 if (rc) { 646 dev_err(&pdev->dev, "Error writing %u to remote spad %d\n", 647 (u32) ntb_get_mw_size(ndev, i), 648 MW0_SZ_LOW + (i * 2)); 649 goto out; 650 } 651 } 652 653 rc = ntb_write_remote_spad(ndev, NUM_MWS, NTB_NUM_MW); 654 if (rc) { 655 dev_err(&pdev->dev, "Error writing %x to remote spad %d\n", 656 NTB_NUM_MW, NUM_MWS); 657 goto out; 658 } 659 660 rc = ntb_write_remote_spad(ndev, NUM_QPS, nt->max_qps); 661 if (rc) { 662 dev_err(&pdev->dev, "Error writing %x to remote spad %d\n", 663 nt->max_qps, NUM_QPS); 664 goto out; 665 } 666 667 rc = ntb_write_remote_spad(ndev, VERSION, NTB_TRANSPORT_VERSION); 668 if (rc) { 669 dev_err(&pdev->dev, "Error writing %x to remote spad %d\n", 670 NTB_TRANSPORT_VERSION, VERSION); 671 goto out; 672 } 673 674 /* Query the remote side for its info */ 675 rc = ntb_read_remote_spad(ndev, VERSION, &val); 676 if (rc) { 677 dev_err(&pdev->dev, "Error reading remote spad %d\n", VERSION); 678 goto out; 679 } 680 681 if (val != NTB_TRANSPORT_VERSION) 682 goto out; 683 dev_dbg(&pdev->dev, "Remote version = %d\n", val); 684 685 rc = ntb_read_remote_spad(ndev, NUM_QPS, &val); 686 if (rc) { 687 dev_err(&pdev->dev, "Error reading remote spad %d\n", NUM_QPS); 688 goto out; 689 } 690 691 if (val != nt->max_qps) 692 goto out; 693 dev_dbg(&pdev->dev, "Remote max number of qps = %d\n", val); 694 695 rc = ntb_read_remote_spad(ndev, NUM_MWS, &val); 696 if (rc) { 697 dev_err(&pdev->dev, "Error reading remote spad %d\n", NUM_MWS); 698 goto out; 699 } 700 701 if (val != NTB_NUM_MW) 702 goto out; 703 dev_dbg(&pdev->dev, "Remote number of mws = %d\n", val); 704 705 for (i = 0; i < NTB_NUM_MW; i++) { 706 u64 val64; 707 708 rc = ntb_read_remote_spad(ndev, MW0_SZ_HIGH + (i * 2), &val); 709 if (rc) { 710 dev_err(&pdev->dev, "Error reading remote spad %d\n", 711 MW0_SZ_HIGH + (i * 2)); 712 goto out1; 713 } 714 715 val64 = (u64) val << 32; 716 717 rc = ntb_read_remote_spad(ndev, MW0_SZ_LOW + (i * 2), &val); 718 if (rc) { 719 dev_err(&pdev->dev, "Error reading remote spad %d\n", 720 MW0_SZ_LOW + (i * 2)); 721 goto out1; 722 } 723 724 val64 |= val; 725 726 dev_dbg(&pdev->dev, "Remote MW%d size = %llu\n", i, val64); 727 728 rc = ntb_set_mw(nt, i, val64); 729 if (rc) 730 goto out1; 731 } 732 733 nt->transport_link = NTB_LINK_UP; 734 735 for (i = 0; i < nt->max_qps; i++) { 736 struct ntb_transport_qp *qp = &nt->qps[i]; 737 738 ntb_transport_setup_qp_mw(nt, i); 739 740 if (qp->client_ready == NTB_LINK_UP) 741 schedule_delayed_work(&qp->link_work, 0); 742 } 743 744 return; 745 746 out1: 747 for (i = 0; i < NTB_NUM_MW; i++) 748 ntb_free_mw(nt, i); 749 out: 750 if (ntb_hw_link_status(ndev)) 751 schedule_delayed_work(&nt->link_work, 752 msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT)); 753 } 754 755 static void ntb_qp_link_work(struct work_struct *work) 756 { 757 struct ntb_transport_qp *qp = container_of(work, 758 struct ntb_transport_qp, 759 link_work.work); 760 struct pci_dev *pdev = ntb_query_pdev(qp->ndev); 761 struct ntb_transport *nt = qp->transport; 762 int rc, val; 763 764 WARN_ON(nt->transport_link != NTB_LINK_UP); 765 766 rc = ntb_read_local_spad(nt->ndev, QP_LINKS, &val); 767 if (rc) { 768 dev_err(&pdev->dev, "Error reading spad %d\n", QP_LINKS); 769 return; 770 } 771 772 rc = ntb_write_remote_spad(nt->ndev, QP_LINKS, val | 1 << qp->qp_num); 773 if (rc) 774 dev_err(&pdev->dev, "Error writing %x to remote spad %d\n", 775 val | 1 << qp->qp_num, QP_LINKS); 776 777 /* query remote spad for qp ready bits */ 778 rc = ntb_read_remote_spad(nt->ndev, QP_LINKS, &val); 779 if (rc) 780 dev_err(&pdev->dev, "Error reading remote spad %d\n", QP_LINKS); 781 782 dev_dbg(&pdev->dev, "Remote QP link status = %x\n", val); 783 784 /* See if the remote side is up */ 785 if (1 << qp->qp_num & val) { 786 qp->qp_link = NTB_LINK_UP; 787 788 dev_info(&pdev->dev, "qp %d: Link Up\n", qp->qp_num); 789 if (qp->event_handler) 790 qp->event_handler(qp->cb_data, NTB_LINK_UP); 791 } else if (nt->transport_link == NTB_LINK_UP) 792 schedule_delayed_work(&qp->link_work, 793 msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT)); 794 } 795 796 static void ntb_transport_init_queue(struct ntb_transport *nt, 797 unsigned int qp_num) 798 { 799 struct ntb_transport_qp *qp; 800 unsigned int num_qps_mw, tx_size; 801 u8 mw_num = QP_TO_MW(qp_num); 802 803 qp = &nt->qps[qp_num]; 804 qp->qp_num = qp_num; 805 qp->transport = nt; 806 qp->ndev = nt->ndev; 807 qp->qp_link = NTB_LINK_DOWN; 808 qp->client_ready = NTB_LINK_DOWN; 809 qp->event_handler = NULL; 810 811 if (nt->max_qps % NTB_NUM_MW && mw_num < nt->max_qps % NTB_NUM_MW) 812 num_qps_mw = nt->max_qps / NTB_NUM_MW + 1; 813 else 814 num_qps_mw = nt->max_qps / NTB_NUM_MW; 815 816 tx_size = (unsigned int) ntb_get_mw_size(qp->ndev, mw_num) / num_qps_mw; 817 qp->rx_info = ntb_get_mw_vbase(nt->ndev, mw_num) + 818 (qp_num / NTB_NUM_MW * tx_size); 819 tx_size -= sizeof(struct ntb_rx_info); 820 821 qp->tx_mw = qp->rx_info + 1; 822 /* Due to housekeeping, there must be atleast 2 buffs */ 823 qp->tx_max_frame = min(transport_mtu, tx_size / 2); 824 qp->tx_max_entry = tx_size / qp->tx_max_frame; 825 826 if (ntb_query_debugfs(nt->ndev)) { 827 char debugfs_name[4]; 828 829 snprintf(debugfs_name, 4, "qp%d", qp_num); 830 qp->debugfs_dir = debugfs_create_dir(debugfs_name, 831 ntb_query_debugfs(nt->ndev)); 832 833 qp->debugfs_stats = debugfs_create_file("stats", S_IRUSR, 834 qp->debugfs_dir, qp, 835 &ntb_qp_debugfs_stats); 836 } 837 838 INIT_DELAYED_WORK(&qp->link_work, ntb_qp_link_work); 839 INIT_WORK(&qp->link_cleanup, ntb_qp_link_cleanup); 840 841 spin_lock_init(&qp->ntb_rx_pend_q_lock); 842 spin_lock_init(&qp->ntb_rx_free_q_lock); 843 spin_lock_init(&qp->ntb_tx_free_q_lock); 844 845 INIT_LIST_HEAD(&qp->rx_pend_q); 846 INIT_LIST_HEAD(&qp->rx_free_q); 847 INIT_LIST_HEAD(&qp->tx_free_q); 848 } 849 850 int ntb_transport_init(struct pci_dev *pdev) 851 { 852 struct ntb_transport *nt; 853 int rc, i; 854 855 nt = kzalloc(sizeof(struct ntb_transport), GFP_KERNEL); 856 if (!nt) 857 return -ENOMEM; 858 859 nt->ndev = ntb_register_transport(pdev, nt); 860 if (!nt->ndev) { 861 rc = -EIO; 862 goto err; 863 } 864 865 nt->max_qps = min(nt->ndev->max_cbs, max_num_clients); 866 867 nt->qps = kcalloc(nt->max_qps, sizeof(struct ntb_transport_qp), 868 GFP_KERNEL); 869 if (!nt->qps) { 870 rc = -ENOMEM; 871 goto err1; 872 } 873 874 nt->qp_bitmap = ((u64) 1 << nt->max_qps) - 1; 875 876 for (i = 0; i < nt->max_qps; i++) 877 ntb_transport_init_queue(nt, i); 878 879 INIT_DELAYED_WORK(&nt->link_work, ntb_transport_link_work); 880 INIT_WORK(&nt->link_cleanup, ntb_transport_link_cleanup); 881 882 rc = ntb_register_event_callback(nt->ndev, 883 ntb_transport_event_callback); 884 if (rc) 885 goto err2; 886 887 INIT_LIST_HEAD(&nt->client_devs); 888 rc = ntb_bus_init(nt); 889 if (rc) 890 goto err3; 891 892 if (ntb_hw_link_status(nt->ndev)) 893 schedule_delayed_work(&nt->link_work, 0); 894 895 return 0; 896 897 err3: 898 ntb_unregister_event_callback(nt->ndev); 899 err2: 900 kfree(nt->qps); 901 err1: 902 ntb_unregister_transport(nt->ndev); 903 err: 904 kfree(nt); 905 return rc; 906 } 907 908 void ntb_transport_free(void *transport) 909 { 910 struct ntb_transport *nt = transport; 911 struct pci_dev *pdev; 912 int i; 913 914 nt->transport_link = NTB_LINK_DOWN; 915 916 /* verify that all the qp's are freed */ 917 for (i = 0; i < nt->max_qps; i++) { 918 if (!test_bit(i, &nt->qp_bitmap)) 919 ntb_transport_free_queue(&nt->qps[i]); 920 debugfs_remove_recursive(nt->qps[i].debugfs_dir); 921 } 922 923 ntb_bus_remove(nt); 924 925 cancel_delayed_work_sync(&nt->link_work); 926 927 ntb_unregister_event_callback(nt->ndev); 928 929 pdev = ntb_query_pdev(nt->ndev); 930 931 for (i = 0; i < NTB_NUM_MW; i++) 932 ntb_free_mw(nt, i); 933 934 kfree(nt->qps); 935 ntb_unregister_transport(nt->ndev); 936 kfree(nt); 937 } 938 939 static void ntb_rx_copy_task(struct ntb_transport_qp *qp, 940 struct ntb_queue_entry *entry, void *offset) 941 { 942 void *cb_data = entry->cb_data; 943 unsigned int len = entry->len; 944 945 memcpy(entry->buf, offset, entry->len); 946 947 ntb_list_add(&qp->ntb_rx_free_q_lock, &entry->entry, &qp->rx_free_q); 948 949 if (qp->rx_handler && qp->client_ready == NTB_LINK_UP) 950 qp->rx_handler(qp, qp->cb_data, cb_data, len); 951 } 952 953 static int ntb_process_rxc(struct ntb_transport_qp *qp) 954 { 955 struct ntb_payload_header *hdr; 956 struct ntb_queue_entry *entry; 957 void *offset; 958 959 offset = qp->rx_buff + qp->rx_max_frame * qp->rx_index; 960 hdr = offset + qp->rx_max_frame - sizeof(struct ntb_payload_header); 961 962 entry = ntb_list_rm(&qp->ntb_rx_pend_q_lock, &qp->rx_pend_q); 963 if (!entry) { 964 dev_dbg(&ntb_query_pdev(qp->ndev)->dev, 965 "no buffer - HDR ver %u, len %d, flags %x\n", 966 hdr->ver, hdr->len, hdr->flags); 967 qp->rx_err_no_buf++; 968 return -ENOMEM; 969 } 970 971 if (!(hdr->flags & DESC_DONE_FLAG)) { 972 ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, 973 &qp->rx_pend_q); 974 qp->rx_ring_empty++; 975 return -EAGAIN; 976 } 977 978 if (hdr->ver != (u32) qp->rx_pkts) { 979 dev_dbg(&ntb_query_pdev(qp->ndev)->dev, 980 "qp %d: version mismatch, expected %llu - got %u\n", 981 qp->qp_num, qp->rx_pkts, hdr->ver); 982 ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, 983 &qp->rx_pend_q); 984 qp->rx_err_ver++; 985 return -EIO; 986 } 987 988 if (hdr->flags & LINK_DOWN_FLAG) { 989 ntb_qp_link_down(qp); 990 991 ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, 992 &qp->rx_pend_q); 993 goto out; 994 } 995 996 dev_dbg(&ntb_query_pdev(qp->ndev)->dev, 997 "rx offset %u, ver %u - %d payload received, buf size %d\n", 998 qp->rx_index, hdr->ver, hdr->len, entry->len); 999 1000 if (hdr->len <= entry->len) { 1001 entry->len = hdr->len; 1002 ntb_rx_copy_task(qp, entry, offset); 1003 } else { 1004 ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, 1005 &qp->rx_pend_q); 1006 1007 qp->rx_err_oflow++; 1008 dev_dbg(&ntb_query_pdev(qp->ndev)->dev, 1009 "RX overflow! Wanted %d got %d\n", 1010 hdr->len, entry->len); 1011 } 1012 1013 qp->rx_bytes += hdr->len; 1014 qp->rx_pkts++; 1015 1016 out: 1017 /* Ensure that the data is fully copied out before clearing the flag */ 1018 wmb(); 1019 hdr->flags = 0; 1020 iowrite32(qp->rx_index, &qp->rx_info->entry); 1021 1022 qp->rx_index++; 1023 qp->rx_index %= qp->rx_max_entry; 1024 1025 return 0; 1026 } 1027 1028 static void ntb_transport_rx(unsigned long data) 1029 { 1030 struct ntb_transport_qp *qp = (struct ntb_transport_qp *)data; 1031 int rc, i; 1032 1033 /* Limit the number of packets processed in a single interrupt to 1034 * provide fairness to others 1035 */ 1036 for (i = 0; i < qp->rx_max_entry; i++) { 1037 rc = ntb_process_rxc(qp); 1038 if (rc) 1039 break; 1040 } 1041 } 1042 1043 static void ntb_transport_rxc_db(void *data, int db_num) 1044 { 1045 struct ntb_transport_qp *qp = data; 1046 1047 dev_dbg(&ntb_query_pdev(qp->ndev)->dev, "%s: doorbell %d received\n", 1048 __func__, db_num); 1049 1050 tasklet_schedule(&qp->rx_work); 1051 } 1052 1053 static void ntb_tx_copy_task(struct ntb_transport_qp *qp, 1054 struct ntb_queue_entry *entry, 1055 void __iomem *offset) 1056 { 1057 struct ntb_payload_header __iomem *hdr; 1058 1059 memcpy_toio(offset, entry->buf, entry->len); 1060 1061 hdr = offset + qp->tx_max_frame - sizeof(struct ntb_payload_header); 1062 iowrite32(entry->len, &hdr->len); 1063 iowrite32((u32) qp->tx_pkts, &hdr->ver); 1064 1065 /* Ensure that the data is fully copied out before setting the flag */ 1066 wmb(); 1067 iowrite32(entry->flags | DESC_DONE_FLAG, &hdr->flags); 1068 1069 ntb_ring_sdb(qp->ndev, qp->qp_num); 1070 1071 /* The entry length can only be zero if the packet is intended to be a 1072 * "link down" or similar. Since no payload is being sent in these 1073 * cases, there is nothing to add to the completion queue. 1074 */ 1075 if (entry->len > 0) { 1076 qp->tx_bytes += entry->len; 1077 1078 if (qp->tx_handler) 1079 qp->tx_handler(qp, qp->cb_data, entry->cb_data, 1080 entry->len); 1081 } 1082 1083 ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, &qp->tx_free_q); 1084 } 1085 1086 static int ntb_process_tx(struct ntb_transport_qp *qp, 1087 struct ntb_queue_entry *entry) 1088 { 1089 void __iomem *offset; 1090 1091 offset = qp->tx_mw + qp->tx_max_frame * qp->tx_index; 1092 1093 dev_dbg(&ntb_query_pdev(qp->ndev)->dev, "%lld - offset %p, tx %u, entry len %d flags %x buff %p\n", 1094 qp->tx_pkts, offset, qp->tx_index, entry->len, entry->flags, 1095 entry->buf); 1096 if (qp->tx_index == qp->remote_rx_info->entry) { 1097 qp->tx_ring_full++; 1098 return -EAGAIN; 1099 } 1100 1101 if (entry->len > qp->tx_max_frame - sizeof(struct ntb_payload_header)) { 1102 if (qp->tx_handler) 1103 qp->tx_handler(qp->cb_data, qp, NULL, -EIO); 1104 1105 ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, 1106 &qp->tx_free_q); 1107 return 0; 1108 } 1109 1110 ntb_tx_copy_task(qp, entry, offset); 1111 1112 qp->tx_index++; 1113 qp->tx_index %= qp->tx_max_entry; 1114 1115 qp->tx_pkts++; 1116 1117 return 0; 1118 } 1119 1120 static void ntb_send_link_down(struct ntb_transport_qp *qp) 1121 { 1122 struct pci_dev *pdev = ntb_query_pdev(qp->ndev); 1123 struct ntb_queue_entry *entry; 1124 int i, rc; 1125 1126 if (qp->qp_link == NTB_LINK_DOWN) 1127 return; 1128 1129 qp->qp_link = NTB_LINK_DOWN; 1130 dev_info(&pdev->dev, "qp %d: Link Down\n", qp->qp_num); 1131 1132 for (i = 0; i < NTB_LINK_DOWN_TIMEOUT; i++) { 1133 entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q); 1134 if (entry) 1135 break; 1136 msleep(100); 1137 } 1138 1139 if (!entry) 1140 return; 1141 1142 entry->cb_data = NULL; 1143 entry->buf = NULL; 1144 entry->len = 0; 1145 entry->flags = LINK_DOWN_FLAG; 1146 1147 rc = ntb_process_tx(qp, entry); 1148 if (rc) 1149 dev_err(&pdev->dev, "ntb: QP%d unable to send linkdown msg\n", 1150 qp->qp_num); 1151 } 1152 1153 /** 1154 * ntb_transport_create_queue - Create a new NTB transport layer queue 1155 * @rx_handler: receive callback function 1156 * @tx_handler: transmit callback function 1157 * @event_handler: event callback function 1158 * 1159 * Create a new NTB transport layer queue and provide the queue with a callback 1160 * routine for both transmit and receive. The receive callback routine will be 1161 * used to pass up data when the transport has received it on the queue. The 1162 * transmit callback routine will be called when the transport has completed the 1163 * transmission of the data on the queue and the data is ready to be freed. 1164 * 1165 * RETURNS: pointer to newly created ntb_queue, NULL on error. 1166 */ 1167 struct ntb_transport_qp * 1168 ntb_transport_create_queue(void *data, struct pci_dev *pdev, 1169 const struct ntb_queue_handlers *handlers) 1170 { 1171 struct ntb_queue_entry *entry; 1172 struct ntb_transport_qp *qp; 1173 struct ntb_transport *nt; 1174 unsigned int free_queue; 1175 int rc, i; 1176 1177 nt = ntb_find_transport(pdev); 1178 if (!nt) 1179 goto err; 1180 1181 free_queue = ffs(nt->qp_bitmap); 1182 if (!free_queue) 1183 goto err; 1184 1185 /* decrement free_queue to make it zero based */ 1186 free_queue--; 1187 1188 clear_bit(free_queue, &nt->qp_bitmap); 1189 1190 qp = &nt->qps[free_queue]; 1191 qp->cb_data = data; 1192 qp->rx_handler = handlers->rx_handler; 1193 qp->tx_handler = handlers->tx_handler; 1194 qp->event_handler = handlers->event_handler; 1195 1196 for (i = 0; i < NTB_QP_DEF_NUM_ENTRIES; i++) { 1197 entry = kzalloc(sizeof(struct ntb_queue_entry), GFP_ATOMIC); 1198 if (!entry) 1199 goto err1; 1200 1201 ntb_list_add(&qp->ntb_rx_free_q_lock, &entry->entry, 1202 &qp->rx_free_q); 1203 } 1204 1205 for (i = 0; i < NTB_QP_DEF_NUM_ENTRIES; i++) { 1206 entry = kzalloc(sizeof(struct ntb_queue_entry), GFP_ATOMIC); 1207 if (!entry) 1208 goto err2; 1209 1210 ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, 1211 &qp->tx_free_q); 1212 } 1213 1214 tasklet_init(&qp->rx_work, ntb_transport_rx, (unsigned long) qp); 1215 1216 rc = ntb_register_db_callback(qp->ndev, free_queue, qp, 1217 ntb_transport_rxc_db); 1218 if (rc) 1219 goto err3; 1220 1221 dev_info(&pdev->dev, "NTB Transport QP %d created\n", qp->qp_num); 1222 1223 return qp; 1224 1225 err3: 1226 tasklet_disable(&qp->rx_work); 1227 err2: 1228 while ((entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q))) 1229 kfree(entry); 1230 err1: 1231 while ((entry = ntb_list_rm(&qp->ntb_rx_free_q_lock, &qp->rx_free_q))) 1232 kfree(entry); 1233 set_bit(free_queue, &nt->qp_bitmap); 1234 err: 1235 return NULL; 1236 } 1237 EXPORT_SYMBOL_GPL(ntb_transport_create_queue); 1238 1239 /** 1240 * ntb_transport_free_queue - Frees NTB transport queue 1241 * @qp: NTB queue to be freed 1242 * 1243 * Frees NTB transport queue 1244 */ 1245 void ntb_transport_free_queue(struct ntb_transport_qp *qp) 1246 { 1247 struct pci_dev *pdev; 1248 struct ntb_queue_entry *entry; 1249 1250 if (!qp) 1251 return; 1252 1253 pdev = ntb_query_pdev(qp->ndev); 1254 1255 cancel_delayed_work_sync(&qp->link_work); 1256 1257 ntb_unregister_db_callback(qp->ndev, qp->qp_num); 1258 tasklet_disable(&qp->rx_work); 1259 1260 while ((entry = ntb_list_rm(&qp->ntb_rx_free_q_lock, &qp->rx_free_q))) 1261 kfree(entry); 1262 1263 while ((entry = ntb_list_rm(&qp->ntb_rx_pend_q_lock, &qp->rx_pend_q))) { 1264 dev_warn(&pdev->dev, "Freeing item from a non-empty queue\n"); 1265 kfree(entry); 1266 } 1267 1268 while ((entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q))) 1269 kfree(entry); 1270 1271 set_bit(qp->qp_num, &qp->transport->qp_bitmap); 1272 1273 dev_info(&pdev->dev, "NTB Transport QP %d freed\n", qp->qp_num); 1274 } 1275 EXPORT_SYMBOL_GPL(ntb_transport_free_queue); 1276 1277 /** 1278 * ntb_transport_rx_remove - Dequeues enqueued rx packet 1279 * @qp: NTB queue to be freed 1280 * @len: pointer to variable to write enqueued buffers length 1281 * 1282 * Dequeues unused buffers from receive queue. Should only be used during 1283 * shutdown of qp. 1284 * 1285 * RETURNS: NULL error value on error, or void* for success. 1286 */ 1287 void *ntb_transport_rx_remove(struct ntb_transport_qp *qp, unsigned int *len) 1288 { 1289 struct ntb_queue_entry *entry; 1290 void *buf; 1291 1292 if (!qp || qp->client_ready == NTB_LINK_UP) 1293 return NULL; 1294 1295 entry = ntb_list_rm(&qp->ntb_rx_pend_q_lock, &qp->rx_pend_q); 1296 if (!entry) 1297 return NULL; 1298 1299 buf = entry->cb_data; 1300 *len = entry->len; 1301 1302 ntb_list_add(&qp->ntb_rx_free_q_lock, &entry->entry, &qp->rx_free_q); 1303 1304 return buf; 1305 } 1306 EXPORT_SYMBOL_GPL(ntb_transport_rx_remove); 1307 1308 /** 1309 * ntb_transport_rx_enqueue - Enqueue a new NTB queue entry 1310 * @qp: NTB transport layer queue the entry is to be enqueued on 1311 * @cb: per buffer pointer for callback function to use 1312 * @data: pointer to data buffer that incoming packets will be copied into 1313 * @len: length of the data buffer 1314 * 1315 * Enqueue a new receive buffer onto the transport queue into which a NTB 1316 * payload can be received into. 1317 * 1318 * RETURNS: An appropriate -ERRNO error value on error, or zero for success. 1319 */ 1320 int ntb_transport_rx_enqueue(struct ntb_transport_qp *qp, void *cb, void *data, 1321 unsigned int len) 1322 { 1323 struct ntb_queue_entry *entry; 1324 1325 if (!qp) 1326 return -EINVAL; 1327 1328 entry = ntb_list_rm(&qp->ntb_rx_free_q_lock, &qp->rx_free_q); 1329 if (!entry) 1330 return -ENOMEM; 1331 1332 entry->cb_data = cb; 1333 entry->buf = data; 1334 entry->len = len; 1335 1336 ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, &qp->rx_pend_q); 1337 1338 return 0; 1339 } 1340 EXPORT_SYMBOL_GPL(ntb_transport_rx_enqueue); 1341 1342 /** 1343 * ntb_transport_tx_enqueue - Enqueue a new NTB queue entry 1344 * @qp: NTB transport layer queue the entry is to be enqueued on 1345 * @cb: per buffer pointer for callback function to use 1346 * @data: pointer to data buffer that will be sent 1347 * @len: length of the data buffer 1348 * 1349 * Enqueue a new transmit buffer onto the transport queue from which a NTB 1350 * payload will be transmitted. This assumes that a lock is behing held to 1351 * serialize access to the qp. 1352 * 1353 * RETURNS: An appropriate -ERRNO error value on error, or zero for success. 1354 */ 1355 int ntb_transport_tx_enqueue(struct ntb_transport_qp *qp, void *cb, void *data, 1356 unsigned int len) 1357 { 1358 struct ntb_queue_entry *entry; 1359 int rc; 1360 1361 if (!qp || qp->qp_link != NTB_LINK_UP || !len) 1362 return -EINVAL; 1363 1364 entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q); 1365 if (!entry) 1366 return -ENOMEM; 1367 1368 entry->cb_data = cb; 1369 entry->buf = data; 1370 entry->len = len; 1371 entry->flags = 0; 1372 1373 rc = ntb_process_tx(qp, entry); 1374 if (rc) 1375 ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, 1376 &qp->tx_free_q); 1377 1378 return rc; 1379 } 1380 EXPORT_SYMBOL_GPL(ntb_transport_tx_enqueue); 1381 1382 /** 1383 * ntb_transport_link_up - Notify NTB transport of client readiness to use queue 1384 * @qp: NTB transport layer queue to be enabled 1385 * 1386 * Notify NTB transport layer of client readiness to use queue 1387 */ 1388 void ntb_transport_link_up(struct ntb_transport_qp *qp) 1389 { 1390 if (!qp) 1391 return; 1392 1393 qp->client_ready = NTB_LINK_UP; 1394 1395 if (qp->transport->transport_link == NTB_LINK_UP) 1396 schedule_delayed_work(&qp->link_work, 0); 1397 } 1398 EXPORT_SYMBOL_GPL(ntb_transport_link_up); 1399 1400 /** 1401 * ntb_transport_link_down - Notify NTB transport to no longer enqueue data 1402 * @qp: NTB transport layer queue to be disabled 1403 * 1404 * Notify NTB transport layer of client's desire to no longer receive data on 1405 * transport queue specified. It is the client's responsibility to ensure all 1406 * entries on queue are purged or otherwise handled appropraitely. 1407 */ 1408 void ntb_transport_link_down(struct ntb_transport_qp *qp) 1409 { 1410 struct pci_dev *pdev; 1411 int rc, val; 1412 1413 if (!qp) 1414 return; 1415 1416 pdev = ntb_query_pdev(qp->ndev); 1417 qp->client_ready = NTB_LINK_DOWN; 1418 1419 rc = ntb_read_local_spad(qp->ndev, QP_LINKS, &val); 1420 if (rc) { 1421 dev_err(&pdev->dev, "Error reading spad %d\n", QP_LINKS); 1422 return; 1423 } 1424 1425 rc = ntb_write_remote_spad(qp->ndev, QP_LINKS, 1426 val & ~(1 << qp->qp_num)); 1427 if (rc) 1428 dev_err(&pdev->dev, "Error writing %x to remote spad %d\n", 1429 val & ~(1 << qp->qp_num), QP_LINKS); 1430 1431 if (qp->qp_link == NTB_LINK_UP) 1432 ntb_send_link_down(qp); 1433 else 1434 cancel_delayed_work_sync(&qp->link_work); 1435 } 1436 EXPORT_SYMBOL_GPL(ntb_transport_link_down); 1437 1438 /** 1439 * ntb_transport_link_query - Query transport link state 1440 * @qp: NTB transport layer queue to be queried 1441 * 1442 * Query connectivity to the remote system of the NTB transport queue 1443 * 1444 * RETURNS: true for link up or false for link down 1445 */ 1446 bool ntb_transport_link_query(struct ntb_transport_qp *qp) 1447 { 1448 if (!qp) 1449 return false; 1450 1451 return qp->qp_link == NTB_LINK_UP; 1452 } 1453 EXPORT_SYMBOL_GPL(ntb_transport_link_query); 1454 1455 /** 1456 * ntb_transport_qp_num - Query the qp number 1457 * @qp: NTB transport layer queue to be queried 1458 * 1459 * Query qp number of the NTB transport queue 1460 * 1461 * RETURNS: a zero based number specifying the qp number 1462 */ 1463 unsigned char ntb_transport_qp_num(struct ntb_transport_qp *qp) 1464 { 1465 if (!qp) 1466 return 0; 1467 1468 return qp->qp_num; 1469 } 1470 EXPORT_SYMBOL_GPL(ntb_transport_qp_num); 1471 1472 /** 1473 * ntb_transport_max_size - Query the max payload size of a qp 1474 * @qp: NTB transport layer queue to be queried 1475 * 1476 * Query the maximum payload size permissible on the given qp 1477 * 1478 * RETURNS: the max payload size of a qp 1479 */ 1480 unsigned int ntb_transport_max_size(struct ntb_transport_qp *qp) 1481 { 1482 if (!qp) 1483 return 0; 1484 1485 return qp->tx_max_frame - sizeof(struct ntb_payload_header); 1486 } 1487 EXPORT_SYMBOL_GPL(ntb_transport_max_size); 1488