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 struct dentry *debugfs_dir; 161 }; 162 163 enum { 164 DESC_DONE_FLAG = 1 << 0, 165 LINK_DOWN_FLAG = 1 << 1, 166 }; 167 168 struct ntb_payload_header { 169 unsigned int ver; 170 unsigned int len; 171 unsigned int flags; 172 }; 173 174 enum { 175 VERSION = 0, 176 QP_LINKS, 177 NUM_QPS, 178 NUM_MWS, 179 MW0_SZ_HIGH, 180 MW0_SZ_LOW, 181 MW1_SZ_HIGH, 182 MW1_SZ_LOW, 183 MAX_SPAD, 184 }; 185 186 #define QP_TO_MW(qp) ((qp) % NTB_NUM_MW) 187 #define NTB_QP_DEF_NUM_ENTRIES 100 188 #define NTB_LINK_DOWN_TIMEOUT 10 189 190 static int ntb_match_bus(struct device *dev, struct device_driver *drv) 191 { 192 return !strncmp(dev_name(dev), drv->name, strlen(drv->name)); 193 } 194 195 static int ntb_client_probe(struct device *dev) 196 { 197 const struct ntb_client *drv = container_of(dev->driver, 198 struct ntb_client, driver); 199 struct pci_dev *pdev = container_of(dev->parent, struct pci_dev, dev); 200 int rc = -EINVAL; 201 202 get_device(dev); 203 if (drv && drv->probe) 204 rc = drv->probe(pdev); 205 if (rc) 206 put_device(dev); 207 208 return rc; 209 } 210 211 static int ntb_client_remove(struct device *dev) 212 { 213 const struct ntb_client *drv = container_of(dev->driver, 214 struct ntb_client, driver); 215 struct pci_dev *pdev = container_of(dev->parent, struct pci_dev, dev); 216 217 if (drv && drv->remove) 218 drv->remove(pdev); 219 220 put_device(dev); 221 222 return 0; 223 } 224 225 static struct bus_type ntb_bus_type = { 226 .name = "ntb_bus", 227 .match = ntb_match_bus, 228 .probe = ntb_client_probe, 229 .remove = ntb_client_remove, 230 }; 231 232 static LIST_HEAD(ntb_transport_list); 233 234 static int ntb_bus_init(struct ntb_transport *nt) 235 { 236 if (list_empty(&ntb_transport_list)) { 237 int rc = bus_register(&ntb_bus_type); 238 if (rc) 239 return rc; 240 } 241 242 list_add(&nt->entry, &ntb_transport_list); 243 244 return 0; 245 } 246 247 static void ntb_bus_remove(struct ntb_transport *nt) 248 { 249 struct ntb_transport_client_dev *client_dev, *cd; 250 251 list_for_each_entry_safe(client_dev, cd, &nt->client_devs, entry) { 252 dev_err(client_dev->dev.parent, "%s still attached to bus, removing\n", 253 dev_name(&client_dev->dev)); 254 list_del(&client_dev->entry); 255 device_unregister(&client_dev->dev); 256 } 257 258 list_del(&nt->entry); 259 260 if (list_empty(&ntb_transport_list)) 261 bus_unregister(&ntb_bus_type); 262 } 263 264 static void ntb_client_release(struct device *dev) 265 { 266 struct ntb_transport_client_dev *client_dev; 267 client_dev = container_of(dev, struct ntb_transport_client_dev, dev); 268 269 kfree(client_dev); 270 } 271 272 /** 273 * ntb_unregister_client_dev - Unregister NTB client device 274 * @device_name: Name of NTB client device 275 * 276 * Unregister an NTB client device with the NTB transport layer 277 */ 278 void ntb_unregister_client_dev(char *device_name) 279 { 280 struct ntb_transport_client_dev *client, *cd; 281 struct ntb_transport *nt; 282 283 list_for_each_entry(nt, &ntb_transport_list, entry) 284 list_for_each_entry_safe(client, cd, &nt->client_devs, entry) 285 if (!strncmp(dev_name(&client->dev), device_name, 286 strlen(device_name))) { 287 list_del(&client->entry); 288 device_unregister(&client->dev); 289 } 290 } 291 EXPORT_SYMBOL_GPL(ntb_unregister_client_dev); 292 293 /** 294 * ntb_register_client_dev - Register NTB client device 295 * @device_name: Name of NTB client device 296 * 297 * Register an NTB client device with the NTB transport layer 298 */ 299 int ntb_register_client_dev(char *device_name) 300 { 301 struct ntb_transport_client_dev *client_dev; 302 struct ntb_transport *nt; 303 int rc; 304 305 if (list_empty(&ntb_transport_list)) 306 return -ENODEV; 307 308 list_for_each_entry(nt, &ntb_transport_list, entry) { 309 struct device *dev; 310 311 client_dev = kzalloc(sizeof(struct ntb_transport_client_dev), 312 GFP_KERNEL); 313 if (!client_dev) { 314 rc = -ENOMEM; 315 goto err; 316 } 317 318 dev = &client_dev->dev; 319 320 /* setup and register client devices */ 321 dev_set_name(dev, "%s", device_name); 322 dev->bus = &ntb_bus_type; 323 dev->release = ntb_client_release; 324 dev->parent = &ntb_query_pdev(nt->ndev)->dev; 325 326 rc = device_register(dev); 327 if (rc) { 328 kfree(client_dev); 329 goto err; 330 } 331 332 list_add_tail(&client_dev->entry, &nt->client_devs); 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 (nt->debugfs_dir) { 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 nt->debugfs_dir); 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 if (debugfs_initialized()) 860 nt->debugfs_dir = debugfs_create_dir(KBUILD_MODNAME, NULL); 861 else 862 nt->debugfs_dir = NULL; 863 864 nt->ndev = ntb_register_transport(pdev, nt); 865 if (!nt->ndev) { 866 rc = -EIO; 867 goto err; 868 } 869 870 nt->max_qps = min(nt->ndev->max_cbs, max_num_clients); 871 872 nt->qps = kcalloc(nt->max_qps, sizeof(struct ntb_transport_qp), 873 GFP_KERNEL); 874 if (!nt->qps) { 875 rc = -ENOMEM; 876 goto err1; 877 } 878 879 nt->qp_bitmap = ((u64) 1 << nt->max_qps) - 1; 880 881 for (i = 0; i < nt->max_qps; i++) 882 ntb_transport_init_queue(nt, i); 883 884 INIT_DELAYED_WORK(&nt->link_work, ntb_transport_link_work); 885 INIT_WORK(&nt->link_cleanup, ntb_transport_link_cleanup); 886 887 rc = ntb_register_event_callback(nt->ndev, 888 ntb_transport_event_callback); 889 if (rc) 890 goto err2; 891 892 INIT_LIST_HEAD(&nt->client_devs); 893 rc = ntb_bus_init(nt); 894 if (rc) 895 goto err3; 896 897 if (ntb_hw_link_status(nt->ndev)) 898 schedule_delayed_work(&nt->link_work, 0); 899 900 return 0; 901 902 err3: 903 ntb_unregister_event_callback(nt->ndev); 904 err2: 905 kfree(nt->qps); 906 err1: 907 ntb_unregister_transport(nt->ndev); 908 err: 909 debugfs_remove_recursive(nt->debugfs_dir); 910 kfree(nt); 911 return rc; 912 } 913 914 void ntb_transport_free(void *transport) 915 { 916 struct ntb_transport *nt = transport; 917 struct pci_dev *pdev; 918 int i; 919 920 nt->transport_link = NTB_LINK_DOWN; 921 922 /* verify that all the qp's are freed */ 923 for (i = 0; i < nt->max_qps; i++) 924 if (!test_bit(i, &nt->qp_bitmap)) 925 ntb_transport_free_queue(&nt->qps[i]); 926 927 ntb_bus_remove(nt); 928 929 cancel_delayed_work_sync(&nt->link_work); 930 931 debugfs_remove_recursive(nt->debugfs_dir); 932 933 ntb_unregister_event_callback(nt->ndev); 934 935 pdev = ntb_query_pdev(nt->ndev); 936 937 for (i = 0; i < NTB_NUM_MW; i++) 938 ntb_free_mw(nt, i); 939 940 kfree(nt->qps); 941 ntb_unregister_transport(nt->ndev); 942 kfree(nt); 943 } 944 945 static void ntb_rx_copy_task(struct ntb_transport_qp *qp, 946 struct ntb_queue_entry *entry, void *offset) 947 { 948 void *cb_data = entry->cb_data; 949 unsigned int len = entry->len; 950 951 memcpy(entry->buf, offset, entry->len); 952 953 ntb_list_add(&qp->ntb_rx_free_q_lock, &entry->entry, &qp->rx_free_q); 954 955 if (qp->rx_handler && qp->client_ready == NTB_LINK_UP) 956 qp->rx_handler(qp, qp->cb_data, cb_data, len); 957 } 958 959 static int ntb_process_rxc(struct ntb_transport_qp *qp) 960 { 961 struct ntb_payload_header *hdr; 962 struct ntb_queue_entry *entry; 963 void *offset; 964 965 offset = qp->rx_buff + qp->rx_max_frame * qp->rx_index; 966 hdr = offset + qp->rx_max_frame - sizeof(struct ntb_payload_header); 967 968 entry = ntb_list_rm(&qp->ntb_rx_pend_q_lock, &qp->rx_pend_q); 969 if (!entry) { 970 dev_dbg(&ntb_query_pdev(qp->ndev)->dev, 971 "no buffer - HDR ver %u, len %d, flags %x\n", 972 hdr->ver, hdr->len, hdr->flags); 973 qp->rx_err_no_buf++; 974 return -ENOMEM; 975 } 976 977 if (!(hdr->flags & DESC_DONE_FLAG)) { 978 ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, 979 &qp->rx_pend_q); 980 qp->rx_ring_empty++; 981 return -EAGAIN; 982 } 983 984 if (hdr->ver != (u32) qp->rx_pkts) { 985 dev_dbg(&ntb_query_pdev(qp->ndev)->dev, 986 "qp %d: version mismatch, expected %llu - got %u\n", 987 qp->qp_num, qp->rx_pkts, hdr->ver); 988 ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, 989 &qp->rx_pend_q); 990 qp->rx_err_ver++; 991 return -EIO; 992 } 993 994 if (hdr->flags & LINK_DOWN_FLAG) { 995 ntb_qp_link_down(qp); 996 997 ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, 998 &qp->rx_pend_q); 999 goto out; 1000 } 1001 1002 dev_dbg(&ntb_query_pdev(qp->ndev)->dev, 1003 "rx offset %u, ver %u - %d payload received, buf size %d\n", 1004 qp->rx_index, hdr->ver, hdr->len, entry->len); 1005 1006 if (hdr->len <= entry->len) { 1007 entry->len = hdr->len; 1008 ntb_rx_copy_task(qp, entry, offset); 1009 } else { 1010 ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, 1011 &qp->rx_pend_q); 1012 1013 qp->rx_err_oflow++; 1014 dev_dbg(&ntb_query_pdev(qp->ndev)->dev, 1015 "RX overflow! Wanted %d got %d\n", 1016 hdr->len, entry->len); 1017 } 1018 1019 qp->rx_bytes += hdr->len; 1020 qp->rx_pkts++; 1021 1022 out: 1023 /* Ensure that the data is fully copied out before clearing the flag */ 1024 wmb(); 1025 hdr->flags = 0; 1026 iowrite32(qp->rx_index, &qp->rx_info->entry); 1027 1028 qp->rx_index++; 1029 qp->rx_index %= qp->rx_max_entry; 1030 1031 return 0; 1032 } 1033 1034 static void ntb_transport_rx(unsigned long data) 1035 { 1036 struct ntb_transport_qp *qp = (struct ntb_transport_qp *)data; 1037 int rc; 1038 1039 do { 1040 rc = ntb_process_rxc(qp); 1041 } while (!rc); 1042 } 1043 1044 static void ntb_transport_rxc_db(void *data, int db_num) 1045 { 1046 struct ntb_transport_qp *qp = data; 1047 1048 dev_dbg(&ntb_query_pdev(qp->ndev)->dev, "%s: doorbell %d received\n", 1049 __func__, db_num); 1050 1051 tasklet_schedule(&qp->rx_work); 1052 } 1053 1054 static void ntb_tx_copy_task(struct ntb_transport_qp *qp, 1055 struct ntb_queue_entry *entry, 1056 void __iomem *offset) 1057 { 1058 struct ntb_payload_header __iomem *hdr; 1059 1060 memcpy_toio(offset, entry->buf, entry->len); 1061 1062 hdr = offset + qp->tx_max_frame - sizeof(struct ntb_payload_header); 1063 iowrite32(entry->len, &hdr->len); 1064 iowrite32((u32) qp->tx_pkts, &hdr->ver); 1065 1066 /* Ensure that the data is fully copied out before setting the flag */ 1067 wmb(); 1068 iowrite32(entry->flags | DESC_DONE_FLAG, &hdr->flags); 1069 1070 ntb_ring_sdb(qp->ndev, qp->qp_num); 1071 1072 /* The entry length can only be zero if the packet is intended to be a 1073 * "link down" or similar. Since no payload is being sent in these 1074 * cases, there is nothing to add to the completion queue. 1075 */ 1076 if (entry->len > 0) { 1077 qp->tx_bytes += entry->len; 1078 1079 if (qp->tx_handler) 1080 qp->tx_handler(qp, qp->cb_data, entry->cb_data, 1081 entry->len); 1082 } 1083 1084 ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, &qp->tx_free_q); 1085 } 1086 1087 static int ntb_process_tx(struct ntb_transport_qp *qp, 1088 struct ntb_queue_entry *entry) 1089 { 1090 void __iomem *offset; 1091 1092 offset = qp->tx_mw + qp->tx_max_frame * qp->tx_index; 1093 1094 dev_dbg(&ntb_query_pdev(qp->ndev)->dev, "%lld - offset %p, tx %u, entry len %d flags %x buff %p\n", 1095 qp->tx_pkts, offset, qp->tx_index, entry->len, entry->flags, 1096 entry->buf); 1097 if (qp->tx_index == qp->remote_rx_info->entry) { 1098 qp->tx_ring_full++; 1099 return -EAGAIN; 1100 } 1101 1102 if (entry->len > qp->tx_max_frame - sizeof(struct ntb_payload_header)) { 1103 if (qp->tx_handler) 1104 qp->tx_handler(qp->cb_data, qp, NULL, -EIO); 1105 1106 ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, 1107 &qp->tx_free_q); 1108 return 0; 1109 } 1110 1111 ntb_tx_copy_task(qp, entry, offset); 1112 1113 qp->tx_index++; 1114 qp->tx_index %= qp->tx_max_entry; 1115 1116 qp->tx_pkts++; 1117 1118 return 0; 1119 } 1120 1121 static void ntb_send_link_down(struct ntb_transport_qp *qp) 1122 { 1123 struct pci_dev *pdev = ntb_query_pdev(qp->ndev); 1124 struct ntb_queue_entry *entry; 1125 int i, rc; 1126 1127 if (qp->qp_link == NTB_LINK_DOWN) 1128 return; 1129 1130 qp->qp_link = NTB_LINK_DOWN; 1131 dev_info(&pdev->dev, "qp %d: Link Down\n", qp->qp_num); 1132 1133 for (i = 0; i < NTB_LINK_DOWN_TIMEOUT; i++) { 1134 entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q); 1135 if (entry) 1136 break; 1137 msleep(100); 1138 } 1139 1140 if (!entry) 1141 return; 1142 1143 entry->cb_data = NULL; 1144 entry->buf = NULL; 1145 entry->len = 0; 1146 entry->flags = LINK_DOWN_FLAG; 1147 1148 rc = ntb_process_tx(qp, entry); 1149 if (rc) 1150 dev_err(&pdev->dev, "ntb: QP%d unable to send linkdown msg\n", 1151 qp->qp_num); 1152 } 1153 1154 /** 1155 * ntb_transport_create_queue - Create a new NTB transport layer queue 1156 * @rx_handler: receive callback function 1157 * @tx_handler: transmit callback function 1158 * @event_handler: event callback function 1159 * 1160 * Create a new NTB transport layer queue and provide the queue with a callback 1161 * routine for both transmit and receive. The receive callback routine will be 1162 * used to pass up data when the transport has received it on the queue. The 1163 * transmit callback routine will be called when the transport has completed the 1164 * transmission of the data on the queue and the data is ready to be freed. 1165 * 1166 * RETURNS: pointer to newly created ntb_queue, NULL on error. 1167 */ 1168 struct ntb_transport_qp * 1169 ntb_transport_create_queue(void *data, struct pci_dev *pdev, 1170 const struct ntb_queue_handlers *handlers) 1171 { 1172 struct ntb_queue_entry *entry; 1173 struct ntb_transport_qp *qp; 1174 struct ntb_transport *nt; 1175 unsigned int free_queue; 1176 int rc, i; 1177 1178 nt = ntb_find_transport(pdev); 1179 if (!nt) 1180 goto err; 1181 1182 free_queue = ffs(nt->qp_bitmap); 1183 if (!free_queue) 1184 goto err; 1185 1186 /* decrement free_queue to make it zero based */ 1187 free_queue--; 1188 1189 clear_bit(free_queue, &nt->qp_bitmap); 1190 1191 qp = &nt->qps[free_queue]; 1192 qp->cb_data = data; 1193 qp->rx_handler = handlers->rx_handler; 1194 qp->tx_handler = handlers->tx_handler; 1195 qp->event_handler = handlers->event_handler; 1196 1197 for (i = 0; i < NTB_QP_DEF_NUM_ENTRIES; i++) { 1198 entry = kzalloc(sizeof(struct ntb_queue_entry), GFP_ATOMIC); 1199 if (!entry) 1200 goto err1; 1201 1202 ntb_list_add(&qp->ntb_rx_free_q_lock, &entry->entry, 1203 &qp->rx_free_q); 1204 } 1205 1206 for (i = 0; i < NTB_QP_DEF_NUM_ENTRIES; i++) { 1207 entry = kzalloc(sizeof(struct ntb_queue_entry), GFP_ATOMIC); 1208 if (!entry) 1209 goto err2; 1210 1211 ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, 1212 &qp->tx_free_q); 1213 } 1214 1215 tasklet_init(&qp->rx_work, ntb_transport_rx, (unsigned long) qp); 1216 1217 rc = ntb_register_db_callback(qp->ndev, free_queue, qp, 1218 ntb_transport_rxc_db); 1219 if (rc) 1220 goto err3; 1221 1222 dev_info(&pdev->dev, "NTB Transport QP %d created\n", qp->qp_num); 1223 1224 return qp; 1225 1226 err3: 1227 tasklet_disable(&qp->rx_work); 1228 err2: 1229 while ((entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q))) 1230 kfree(entry); 1231 err1: 1232 while ((entry = ntb_list_rm(&qp->ntb_rx_free_q_lock, &qp->rx_free_q))) 1233 kfree(entry); 1234 set_bit(free_queue, &nt->qp_bitmap); 1235 err: 1236 return NULL; 1237 } 1238 EXPORT_SYMBOL_GPL(ntb_transport_create_queue); 1239 1240 /** 1241 * ntb_transport_free_queue - Frees NTB transport queue 1242 * @qp: NTB queue to be freed 1243 * 1244 * Frees NTB transport queue 1245 */ 1246 void ntb_transport_free_queue(struct ntb_transport_qp *qp) 1247 { 1248 struct pci_dev *pdev; 1249 struct ntb_queue_entry *entry; 1250 1251 if (!qp) 1252 return; 1253 1254 pdev = ntb_query_pdev(qp->ndev); 1255 1256 cancel_delayed_work_sync(&qp->link_work); 1257 1258 ntb_unregister_db_callback(qp->ndev, qp->qp_num); 1259 tasklet_disable(&qp->rx_work); 1260 1261 while ((entry = ntb_list_rm(&qp->ntb_rx_free_q_lock, &qp->rx_free_q))) 1262 kfree(entry); 1263 1264 while ((entry = ntb_list_rm(&qp->ntb_rx_pend_q_lock, &qp->rx_pend_q))) { 1265 dev_warn(&pdev->dev, "Freeing item from a non-empty queue\n"); 1266 kfree(entry); 1267 } 1268 1269 while ((entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q))) 1270 kfree(entry); 1271 1272 set_bit(qp->qp_num, &qp->transport->qp_bitmap); 1273 1274 dev_info(&pdev->dev, "NTB Transport QP %d freed\n", qp->qp_num); 1275 } 1276 EXPORT_SYMBOL_GPL(ntb_transport_free_queue); 1277 1278 /** 1279 * ntb_transport_rx_remove - Dequeues enqueued rx packet 1280 * @qp: NTB queue to be freed 1281 * @len: pointer to variable to write enqueued buffers length 1282 * 1283 * Dequeues unused buffers from receive queue. Should only be used during 1284 * shutdown of qp. 1285 * 1286 * RETURNS: NULL error value on error, or void* for success. 1287 */ 1288 void *ntb_transport_rx_remove(struct ntb_transport_qp *qp, unsigned int *len) 1289 { 1290 struct ntb_queue_entry *entry; 1291 void *buf; 1292 1293 if (!qp || qp->client_ready == NTB_LINK_UP) 1294 return NULL; 1295 1296 entry = ntb_list_rm(&qp->ntb_rx_pend_q_lock, &qp->rx_pend_q); 1297 if (!entry) 1298 return NULL; 1299 1300 buf = entry->cb_data; 1301 *len = entry->len; 1302 1303 ntb_list_add(&qp->ntb_rx_free_q_lock, &entry->entry, &qp->rx_free_q); 1304 1305 return buf; 1306 } 1307 EXPORT_SYMBOL_GPL(ntb_transport_rx_remove); 1308 1309 /** 1310 * ntb_transport_rx_enqueue - Enqueue a new NTB queue entry 1311 * @qp: NTB transport layer queue the entry is to be enqueued on 1312 * @cb: per buffer pointer for callback function to use 1313 * @data: pointer to data buffer that incoming packets will be copied into 1314 * @len: length of the data buffer 1315 * 1316 * Enqueue a new receive buffer onto the transport queue into which a NTB 1317 * payload can be received into. 1318 * 1319 * RETURNS: An appropriate -ERRNO error value on error, or zero for success. 1320 */ 1321 int ntb_transport_rx_enqueue(struct ntb_transport_qp *qp, void *cb, void *data, 1322 unsigned int len) 1323 { 1324 struct ntb_queue_entry *entry; 1325 1326 if (!qp) 1327 return -EINVAL; 1328 1329 entry = ntb_list_rm(&qp->ntb_rx_free_q_lock, &qp->rx_free_q); 1330 if (!entry) 1331 return -ENOMEM; 1332 1333 entry->cb_data = cb; 1334 entry->buf = data; 1335 entry->len = len; 1336 1337 ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, &qp->rx_pend_q); 1338 1339 return 0; 1340 } 1341 EXPORT_SYMBOL_GPL(ntb_transport_rx_enqueue); 1342 1343 /** 1344 * ntb_transport_tx_enqueue - Enqueue a new NTB queue entry 1345 * @qp: NTB transport layer queue the entry is to be enqueued on 1346 * @cb: per buffer pointer for callback function to use 1347 * @data: pointer to data buffer that will be sent 1348 * @len: length of the data buffer 1349 * 1350 * Enqueue a new transmit buffer onto the transport queue from which a NTB 1351 * payload will be transmitted. This assumes that a lock is behing held to 1352 * serialize access to the qp. 1353 * 1354 * RETURNS: An appropriate -ERRNO error value on error, or zero for success. 1355 */ 1356 int ntb_transport_tx_enqueue(struct ntb_transport_qp *qp, void *cb, void *data, 1357 unsigned int len) 1358 { 1359 struct ntb_queue_entry *entry; 1360 int rc; 1361 1362 if (!qp || qp->qp_link != NTB_LINK_UP || !len) 1363 return -EINVAL; 1364 1365 entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q); 1366 if (!entry) 1367 return -ENOMEM; 1368 1369 entry->cb_data = cb; 1370 entry->buf = data; 1371 entry->len = len; 1372 entry->flags = 0; 1373 1374 rc = ntb_process_tx(qp, entry); 1375 if (rc) 1376 ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, 1377 &qp->tx_free_q); 1378 1379 return rc; 1380 } 1381 EXPORT_SYMBOL_GPL(ntb_transport_tx_enqueue); 1382 1383 /** 1384 * ntb_transport_link_up - Notify NTB transport of client readiness to use queue 1385 * @qp: NTB transport layer queue to be enabled 1386 * 1387 * Notify NTB transport layer of client readiness to use queue 1388 */ 1389 void ntb_transport_link_up(struct ntb_transport_qp *qp) 1390 { 1391 if (!qp) 1392 return; 1393 1394 qp->client_ready = NTB_LINK_UP; 1395 1396 if (qp->transport->transport_link == NTB_LINK_UP) 1397 schedule_delayed_work(&qp->link_work, 0); 1398 } 1399 EXPORT_SYMBOL_GPL(ntb_transport_link_up); 1400 1401 /** 1402 * ntb_transport_link_down - Notify NTB transport to no longer enqueue data 1403 * @qp: NTB transport layer queue to be disabled 1404 * 1405 * Notify NTB transport layer of client's desire to no longer receive data on 1406 * transport queue specified. It is the client's responsibility to ensure all 1407 * entries on queue are purged or otherwise handled appropraitely. 1408 */ 1409 void ntb_transport_link_down(struct ntb_transport_qp *qp) 1410 { 1411 struct pci_dev *pdev; 1412 int rc, val; 1413 1414 if (!qp) 1415 return; 1416 1417 pdev = ntb_query_pdev(qp->ndev); 1418 qp->client_ready = NTB_LINK_DOWN; 1419 1420 rc = ntb_read_local_spad(qp->ndev, QP_LINKS, &val); 1421 if (rc) { 1422 dev_err(&pdev->dev, "Error reading spad %d\n", QP_LINKS); 1423 return; 1424 } 1425 1426 rc = ntb_write_remote_spad(qp->ndev, QP_LINKS, 1427 val & ~(1 << qp->qp_num)); 1428 if (rc) 1429 dev_err(&pdev->dev, "Error writing %x to remote spad %d\n", 1430 val & ~(1 << qp->qp_num), QP_LINKS); 1431 1432 if (qp->qp_link == NTB_LINK_UP) 1433 ntb_send_link_down(qp); 1434 else 1435 cancel_delayed_work_sync(&qp->link_work); 1436 } 1437 EXPORT_SYMBOL_GPL(ntb_transport_link_down); 1438 1439 /** 1440 * ntb_transport_link_query - Query transport link state 1441 * @qp: NTB transport layer queue to be queried 1442 * 1443 * Query connectivity to the remote system of the NTB transport queue 1444 * 1445 * RETURNS: true for link up or false for link down 1446 */ 1447 bool ntb_transport_link_query(struct ntb_transport_qp *qp) 1448 { 1449 if (!qp) 1450 return false; 1451 1452 return qp->qp_link == NTB_LINK_UP; 1453 } 1454 EXPORT_SYMBOL_GPL(ntb_transport_link_query); 1455 1456 /** 1457 * ntb_transport_qp_num - Query the qp number 1458 * @qp: NTB transport layer queue to be queried 1459 * 1460 * Query qp number of the NTB transport queue 1461 * 1462 * RETURNS: a zero based number specifying the qp number 1463 */ 1464 unsigned char ntb_transport_qp_num(struct ntb_transport_qp *qp) 1465 { 1466 if (!qp) 1467 return 0; 1468 1469 return qp->qp_num; 1470 } 1471 EXPORT_SYMBOL_GPL(ntb_transport_qp_num); 1472 1473 /** 1474 * ntb_transport_max_size - Query the max payload size of a qp 1475 * @qp: NTB transport layer queue to be queried 1476 * 1477 * Query the maximum payload size permissible on the given qp 1478 * 1479 * RETURNS: the max payload size of a qp 1480 */ 1481 unsigned int ntb_transport_max_size(struct ntb_transport_qp *qp) 1482 { 1483 if (!qp) 1484 return 0; 1485 1486 return qp->tx_max_frame - sizeof(struct ntb_payload_header); 1487 } 1488 EXPORT_SYMBOL_GPL(ntb_transport_max_size); 1489