1/*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (C) 2014-2018 Giuseppe Lettieri 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29/* $FreeBSD$ */ 30 31#if defined(__FreeBSD__) 32#include <sys/cdefs.h> /* prerequisite */ 33 34#include <sys/types.h> 35#include <sys/errno.h> 36#include <sys/param.h> /* defines used in kernel.h */ 37#include <sys/kernel.h> /* types used in module initialization */ 38#include <sys/malloc.h> 39#include <sys/poll.h> 40#include <sys/lock.h> 41#include <sys/rwlock.h> 42#include <sys/selinfo.h> 43#include <sys/sysctl.h> 44#include <sys/socket.h> /* sockaddrs */ 45#include <net/if.h> 46#include <net/if_var.h> 47#include <machine/bus.h> /* bus_dmamap_* */ 48#include <sys/refcount.h> 49 50 51#elif defined(linux) 52 53#include "bsd_glue.h" 54 55#elif defined(__APPLE__) 56 57#warning OSX support is only partial 58#include "osx_glue.h" 59 60#elif defined(_WIN32) 61#include "win_glue.h" 62 63#else 64 65#error Unsupported platform 66 67#endif /* unsupported */ 68 69/* 70 * common headers 71 */ 72 73#include <net/netmap.h> 74#include <dev/netmap/netmap_kern.h> 75#include <dev/netmap/netmap_mem2.h> 76 77#ifdef WITH_PIPES 78 79#define NM_PIPE_MAXSLOTS 4096 80#define NM_PIPE_MAXRINGS 256 81 82static int netmap_default_pipes = 0; /* ignored, kept for compatibility */ 83SYSBEGIN(vars_pipes); 84SYSCTL_DECL(_dev_netmap); 85SYSCTL_INT(_dev_netmap, OID_AUTO, default_pipes, CTLFLAG_RW, 86 &netmap_default_pipes, 0, "For compatibility only"); 87SYSEND; 88 89/* allocate the pipe array in the parent adapter */ 90static int 91nm_pipe_alloc(struct netmap_adapter *na, u_int npipes) 92{ 93 size_t old_len, len; 94 struct netmap_pipe_adapter **npa; 95 96 if (npipes <= na->na_max_pipes) 97 /* we already have more entries that requested */ 98 return 0; 99 100 if (npipes < na->na_next_pipe || npipes > NM_MAXPIPES) 101 return EINVAL; 102 103 old_len = sizeof(struct netmap_pipe_adapter *)*na->na_max_pipes; 104 len = sizeof(struct netmap_pipe_adapter *) * npipes; 105 npa = nm_os_realloc(na->na_pipes, len, old_len); 106 if (npa == NULL) 107 return ENOMEM; 108 109 na->na_pipes = npa; 110 na->na_max_pipes = npipes; 111 112 return 0; 113} 114 115/* deallocate the parent array in the parent adapter */ 116void 117netmap_pipe_dealloc(struct netmap_adapter *na) 118{ 119 if (na->na_pipes) { 120 if (na->na_next_pipe > 0) { 121 nm_prerr("freeing not empty pipe array for %s (%d dangling pipes)!", 122 na->name, na->na_next_pipe); 123 } 124 nm_os_free(na->na_pipes); 125 na->na_pipes = NULL; 126 na->na_max_pipes = 0; 127 na->na_next_pipe = 0; 128 } 129} 130 131/* find a pipe endpoint with the given id among the parent's pipes */ 132static struct netmap_pipe_adapter * 133netmap_pipe_find(struct netmap_adapter *parent, const char *pipe_id) 134{ 135 int i; 136 struct netmap_pipe_adapter *na; 137 138 for (i = 0; i < parent->na_next_pipe; i++) { 139 const char *na_pipe_id; 140 na = parent->na_pipes[i]; 141 na_pipe_id = strrchr(na->up.name, 142 na->role == NM_PIPE_ROLE_MASTER ? '{' : '}'); 143 KASSERT(na_pipe_id != NULL, ("Invalid pipe name")); 144 ++na_pipe_id; 145 if (!strcmp(na_pipe_id, pipe_id)) { 146 return na; 147 } 148 } 149 return NULL; 150} 151 152/* add a new pipe endpoint to the parent array */ 153static int 154netmap_pipe_add(struct netmap_adapter *parent, struct netmap_pipe_adapter *na) 155{ 156 if (parent->na_next_pipe >= parent->na_max_pipes) { 157 u_int npipes = parent->na_max_pipes ? 2*parent->na_max_pipes : 2; 158 int error = nm_pipe_alloc(parent, npipes); 159 if (error) 160 return error; 161 } 162 163 parent->na_pipes[parent->na_next_pipe] = na; 164 na->parent_slot = parent->na_next_pipe; 165 parent->na_next_pipe++; 166 return 0; 167} 168 169/* remove the given pipe endpoint from the parent array */ 170static void 171netmap_pipe_remove(struct netmap_adapter *parent, struct netmap_pipe_adapter *na) 172{ 173 u_int n; 174 n = --parent->na_next_pipe; 175 if (n != na->parent_slot) { 176 struct netmap_pipe_adapter **p = 177 &parent->na_pipes[na->parent_slot]; 178 *p = parent->na_pipes[n]; 179 (*p)->parent_slot = na->parent_slot; 180 } 181 parent->na_pipes[n] = NULL; 182} 183 184int 185netmap_pipe_txsync(struct netmap_kring *txkring, int flags) 186{ 187 struct netmap_kring *rxkring = txkring->pipe; 188 u_int k, lim = txkring->nkr_num_slots - 1, nk; 189 int m; /* slots to transfer */ 190 int complete; /* did we see a complete packet ? */ 191 struct netmap_ring *txring = txkring->ring, *rxring = rxkring->ring; 192 193 nm_prdis("%p: %s %x -> %s", txkring, txkring->name, flags, rxkring->name); 194 nm_prdis(20, "TX before: hwcur %d hwtail %d cur %d head %d tail %d", 195 txkring->nr_hwcur, txkring->nr_hwtail, 196 txkring->rcur, txkring->rhead, txkring->rtail); 197 198 /* update the hwtail */ 199 txkring->nr_hwtail = txkring->pipe_tail; 200 201 m = txkring->rhead - txkring->nr_hwcur; /* new slots */ 202 if (m < 0) 203 m += txkring->nkr_num_slots; 204 205 if (m == 0) { 206 /* nothing to send */ 207 return 0; 208 } 209 210 for (k = txkring->nr_hwcur, nk = lim + 1, complete = 0; m; 211 m--, k = nm_next(k, lim), nk = (complete ? k : nk)) { 212 struct netmap_slot *rs = &rxring->slot[k]; 213 struct netmap_slot *ts = &txring->slot[k]; 214 215 *rs = *ts; 216 if (ts->flags & NS_BUF_CHANGED) { 217 ts->flags &= ~NS_BUF_CHANGED; 218 } 219 complete = !(ts->flags & NS_MOREFRAG); 220 } 221 222 txkring->nr_hwcur = k; 223 224 nm_prdis(20, "TX after : hwcur %d hwtail %d cur %d head %d tail %d k %d", 225 txkring->nr_hwcur, txkring->nr_hwtail, 226 txkring->rcur, txkring->rhead, txkring->rtail, k); 227 228 if (likely(nk <= lim)) { 229 mb(); /* make sure the slots are updated before publishing them */ 230 rxkring->pipe_tail = nk; /* only publish complete packets */ 231 rxkring->nm_notify(rxkring, 0); 232 } 233 234 return 0; 235} 236 237int 238netmap_pipe_rxsync(struct netmap_kring *rxkring, int flags) 239{ 240 struct netmap_kring *txkring = rxkring->pipe; 241 u_int k, lim = rxkring->nkr_num_slots - 1; 242 int m; /* slots to release */ 243 struct netmap_ring *txring = txkring->ring, *rxring = rxkring->ring; 244 245 nm_prdis("%p: %s %x -> %s", txkring, txkring->name, flags, rxkring->name); 246 nm_prdis(20, "RX before: hwcur %d hwtail %d cur %d head %d tail %d", 247 rxkring->nr_hwcur, rxkring->nr_hwtail, 248 rxkring->rcur, rxkring->rhead, rxkring->rtail); 249 250 /* update the hwtail */ 251 rxkring->nr_hwtail = rxkring->pipe_tail; 252 253 m = rxkring->rhead - rxkring->nr_hwcur; /* released slots */ 254 if (m < 0) 255 m += rxkring->nkr_num_slots; 256 257 if (m == 0) { 258 /* nothing to release */ 259 return 0; 260 } 261 262 for (k = rxkring->nr_hwcur; m; m--, k = nm_next(k, lim)) { 263 struct netmap_slot *rs = &rxring->slot[k]; 264 struct netmap_slot *ts = &txring->slot[k]; 265 266 if (rs->flags & NS_BUF_CHANGED) { 267 /* copy the slot and report the buffer change */ 268 *ts = *rs; 269 rs->flags &= ~NS_BUF_CHANGED; 270 } 271 } 272 273 mb(); /* make sure the slots are updated before publishing them */ 274 txkring->pipe_tail = nm_prev(k, lim); 275 rxkring->nr_hwcur = k; 276 277 nm_prdis(20, "RX after : hwcur %d hwtail %d cur %d head %d tail %d k %d", 278 rxkring->nr_hwcur, rxkring->nr_hwtail, 279 rxkring->rcur, rxkring->rhead, rxkring->rtail, k); 280 281 txkring->nm_notify(txkring, 0); 282 283 return 0; 284} 285 286/* Pipe endpoints are created and destroyed together, so that endopoints do not 287 * have to check for the existence of their peer at each ?xsync. 288 * 289 * To play well with the existing netmap infrastructure (refcounts etc.), we 290 * adopt the following strategy: 291 * 292 * 1) The first endpoint that is created also creates the other endpoint and 293 * grabs a reference to it. 294 * 295 * state A) user1 --> endpoint1 --> endpoint2 296 * 297 * 2) If, starting from state A, endpoint2 is then registered, endpoint1 gives 298 * its reference to the user: 299 * 300 * state B) user1 --> endpoint1 endpoint2 <--- user2 301 * 302 * 3) Assume that, starting from state B endpoint2 is closed. In the unregister 303 * callback endpoint2 notes that endpoint1 is still active and adds a reference 304 * from endpoint1 to itself. When user2 then releases her own reference, 305 * endpoint2 is not destroyed and we are back to state A. A symmetrical state 306 * would be reached if endpoint1 were released instead. 307 * 308 * 4) If, starting from state A, endpoint1 is closed, the destructor notes that 309 * it owns a reference to endpoint2 and releases it. 310 * 311 * Something similar goes on for the creation and destruction of the krings. 312 */ 313 314 315int netmap_pipe_krings_create_both(struct netmap_adapter *na, 316 struct netmap_adapter *ona) 317{ 318 enum txrx t; 319 int error; 320 int i; 321 322 /* case 1) below */ 323 nm_prdis("%p: case 1, create both ends", na); 324 error = netmap_krings_create(na, 0); 325 if (error) 326 return error; 327 328 /* create the krings of the other end */ 329 error = netmap_krings_create(ona, 0); 330 if (error) 331 goto del_krings1; 332 333 /* cross link the krings and initialize the pipe_tails */ 334 for_rx_tx(t) { 335 enum txrx r = nm_txrx_swap(t); /* swap NR_TX <-> NR_RX */ 336 for (i = 0; i < nma_get_nrings(na, t); i++) { 337 struct netmap_kring *k1 = NMR(na, t)[i], 338 *k2 = NMR(ona, r)[i]; 339 k1->pipe = k2; 340 k2->pipe = k1; 341 /* mark all peer-adapter rings as fake */ 342 k2->nr_kflags |= NKR_FAKERING; 343 /* init tails */ 344 k1->pipe_tail = k1->nr_hwtail; 345 k2->pipe_tail = k2->nr_hwtail; 346 } 347 } 348 349 return 0; 350 351del_krings1: 352 netmap_krings_delete(na); 353 return error; 354} 355 356/* netmap_pipe_krings_create. 357 * 358 * There are two cases: 359 * 360 * 1) state is 361 * 362 * usr1 --> e1 --> e2 363 * 364 * and we are e1. We have to create both sets 365 * of krings. 366 * 367 * 2) state is 368 * 369 * usr1 --> e1 --> e2 370 * 371 * and we are e2. e1 is certainly registered and our 372 * krings already exist. Nothing to do. 373 */ 374static int 375netmap_pipe_krings_create(struct netmap_adapter *na) 376{ 377 struct netmap_pipe_adapter *pna = 378 (struct netmap_pipe_adapter *)na; 379 struct netmap_adapter *ona = &pna->peer->up; 380 381 if (pna->peer_ref) 382 return netmap_pipe_krings_create_both(na, ona); 383 384 return 0; 385} 386 387int 388netmap_pipe_reg_both(struct netmap_adapter *na, struct netmap_adapter *ona) 389{ 390 int i, error = 0; 391 enum txrx t; 392 393 for_rx_tx(t) { 394 for (i = 0; i < nma_get_nrings(na, t); i++) { 395 struct netmap_kring *kring = NMR(na, t)[i]; 396 397 if (nm_kring_pending_on(kring)) { 398 /* mark the peer ring as needed */ 399 kring->pipe->nr_kflags |= NKR_NEEDRING; 400 } 401 } 402 } 403 404 /* create all missing needed rings on the other end. 405 * Either our end, or the other, has been marked as 406 * fake, so the allocation will not be done twice. 407 */ 408 error = netmap_mem_rings_create(ona); 409 if (error) 410 return error; 411 412 /* In case of no error we put our rings in netmap mode */ 413 for_rx_tx(t) { 414 for (i = 0; i < nma_get_nrings(na, t); i++) { 415 struct netmap_kring *kring = NMR(na, t)[i]; 416 if (nm_kring_pending_on(kring)) { 417 struct netmap_kring *sring, *dring; 418 419 kring->nr_mode = NKR_NETMAP_ON; 420 if ((kring->nr_kflags & NKR_FAKERING) && 421 (kring->pipe->nr_kflags & NKR_FAKERING)) { 422 /* this is a re-open of a pipe 423 * end-point kept alive by the other end. 424 * We need to leave everything as it is 425 */ 426 continue; 427 } 428 429 /* copy the buffers from the non-fake ring */ 430 if (kring->nr_kflags & NKR_FAKERING) { 431 sring = kring->pipe; 432 dring = kring; 433 } else { 434 sring = kring; 435 dring = kring->pipe; 436 } 437 memcpy(dring->ring->slot, 438 sring->ring->slot, 439 sizeof(struct netmap_slot) * 440 sring->nkr_num_slots); 441 /* mark both rings as fake and needed, 442 * so that buffers will not be 443 * deleted by the standard machinery 444 * (we will delete them by ourselves in 445 * netmap_pipe_krings_delete) 446 */ 447 sring->nr_kflags |= 448 (NKR_FAKERING | NKR_NEEDRING); 449 dring->nr_kflags |= 450 (NKR_FAKERING | NKR_NEEDRING); 451 kring->nr_mode = NKR_NETMAP_ON; 452 } 453 } 454 } 455 456 return 0; 457} 458 459/* netmap_pipe_reg. 460 * 461 * There are two cases on registration (onoff==1) 462 * 463 * 1.a) state is 464 * 465 * usr1 --> e1 --> e2 466 * 467 * and we are e1. Create the needed rings of the 468 * other end. 469 * 470 * 1.b) state is 471 * 472 * usr1 --> e1 --> e2 <-- usr2 473 * 474 * and we are e2. Drop the ref e1 is holding. 475 * 476 * There are two additional cases on unregister (onoff==0) 477 * 478 * 2.a) state is 479 * 480 * usr1 --> e1 --> e2 481 * 482 * and we are e1. Nothing special to do, e2 will 483 * be cleaned up by the destructor of e1. 484 * 485 * 2.b) state is 486 * 487 * usr1 --> e1 e2 <-- usr2 488 * 489 * and we are either e1 or e2. Add a ref from the 490 * other end. 491 */ 492static int 493netmap_pipe_reg(struct netmap_adapter *na, int onoff) 494{ 495 struct netmap_pipe_adapter *pna = 496 (struct netmap_pipe_adapter *)na; 497 struct netmap_adapter *ona = &pna->peer->up; 498 int error = 0; 499 500 nm_prdis("%p: onoff %d", na, onoff); 501 if (onoff) { 502 error = netmap_pipe_reg_both(na, ona); 503 if (error) { 504 return error; 505 } 506 if (na->active_fds == 0) 507 na->na_flags |= NAF_NETMAP_ON; 508 } else { 509 if (na->active_fds == 0) 510 na->na_flags &= ~NAF_NETMAP_ON; 511 netmap_krings_mode_commit(na, onoff); 512 } 513 514 if (na->active_fds) { 515 nm_prdis("active_fds %d", na->active_fds); 516 return 0; 517 } 518 519 if (pna->peer_ref) { 520 nm_prdis("%p: case 1.a or 2.a, nothing to do", na); 521 return 0; 522 } 523 if (onoff) { 524 nm_prdis("%p: case 1.b, drop peer", na); 525 pna->peer->peer_ref = 0; 526 netmap_adapter_put(na); 527 } else { 528 nm_prdis("%p: case 2.b, grab peer", na); 529 netmap_adapter_get(na); 530 pna->peer->peer_ref = 1; 531 } 532 return error; 533} 534 535void 536netmap_pipe_krings_delete_both(struct netmap_adapter *na, 537 struct netmap_adapter *ona) 538{ 539 struct netmap_adapter *sna; 540 enum txrx t; 541 int i; 542 543 /* case 1) below */ 544 nm_prdis("%p: case 1, deleting everything", na); 545 /* To avoid double-frees we zero-out all the buffers in the kernel part 546 * of each ring. The reason is this: If the user is behaving correctly, 547 * all buffers are found in exactly one slot in the userspace part of 548 * some ring. If the user is not behaving correctly, we cannot release 549 * buffers cleanly anyway. In the latter case, the allocator will 550 * return to a clean state only when all its users will close. 551 */ 552 sna = na; 553cleanup: 554 for_rx_tx(t) { 555 for (i = 0; i < nma_get_nrings(sna, t); i++) { 556 struct netmap_kring *kring = NMR(sna, t)[i]; 557 struct netmap_ring *ring = kring->ring; 558 uint32_t j, lim = kring->nkr_num_slots - 1; 559 560 nm_prdis("%s ring %p hwtail %u hwcur %u", 561 kring->name, ring, kring->nr_hwtail, kring->nr_hwcur); 562 563 if (ring == NULL) 564 continue; 565 566 if (kring->tx == NR_RX) 567 ring->slot[kring->pipe_tail].buf_idx = 0; 568 569 for (j = nm_next(kring->pipe_tail, lim); 570 j != kring->nr_hwcur; 571 j = nm_next(j, lim)) 572 { 573 nm_prdis("%s[%d] %u", kring->name, j, ring->slot[j].buf_idx); 574 ring->slot[j].buf_idx = 0; 575 } 576 kring->nr_kflags &= ~(NKR_FAKERING | NKR_NEEDRING); 577 } 578 579 } 580 if (sna != ona && ona->tx_rings) { 581 sna = ona; 582 goto cleanup; 583 } 584 585 netmap_mem_rings_delete(na); 586 netmap_krings_delete(na); /* also zeroes tx_rings etc. */ 587 588 if (ona->tx_rings == NULL) { 589 /* already deleted, we must be on an 590 * cleanup-after-error path */ 591 return; 592 } 593 netmap_mem_rings_delete(ona); 594 netmap_krings_delete(ona); 595} 596 597/* netmap_pipe_krings_delete. 598 * 599 * There are two cases: 600 * 601 * 1) state is 602 * 603 * usr1 --> e1 --> e2 604 * 605 * and we are e1 (e2 is not registered, so krings_delete cannot be 606 * called on it); 607 * 608 * 2) state is 609 * 610 * usr1 --> e1 e2 <-- usr2 611 * 612 * and we are either e1 or e2. 613 * 614 * In the former case we have to also delete the krings of e2; 615 * in the latter case we do nothing. 616 */ 617static void 618netmap_pipe_krings_delete(struct netmap_adapter *na) 619{ 620 struct netmap_pipe_adapter *pna = 621 (struct netmap_pipe_adapter *)na; 622 struct netmap_adapter *ona; /* na of the other end */ 623 624 if (!pna->peer_ref) { 625 nm_prdis("%p: case 2, kept alive by peer", na); 626 return; 627 } 628 ona = &pna->peer->up; 629 netmap_pipe_krings_delete_both(na, ona); 630} 631 632 633static void 634netmap_pipe_dtor(struct netmap_adapter *na) 635{ 636 struct netmap_pipe_adapter *pna = 637 (struct netmap_pipe_adapter *)na; 638 nm_prdis("%p %p", na, pna->parent_ifp); 639 if (pna->peer_ref) { 640 nm_prdis("%p: clean up peer", na); 641 pna->peer_ref = 0; 642 netmap_adapter_put(&pna->peer->up); 643 } 644 if (pna->role == NM_PIPE_ROLE_MASTER) 645 netmap_pipe_remove(pna->parent, pna); 646 if (pna->parent_ifp) 647 if_rele(pna->parent_ifp); 648 netmap_adapter_put(pna->parent); 649 pna->parent = NULL; 650} 651 652int 653netmap_get_pipe_na(struct nmreq_header *hdr, struct netmap_adapter **na, 654 struct netmap_mem_d *nmd, int create) 655{ 656 struct nmreq_register *req = (struct nmreq_register *)(uintptr_t)hdr->nr_body; 657 struct netmap_adapter *pna; /* parent adapter */ 658 struct netmap_pipe_adapter *mna, *sna, *reqna; 659 struct ifnet *ifp = NULL; 660 const char *pipe_id = NULL; 661 int role = 0; 662 int error, retries = 0; 663 char *cbra; 664 665 /* Try to parse the pipe syntax 'xx{yy' or 'xx}yy'. */ 666 cbra = strrchr(hdr->nr_name, '{'); 667 if (cbra != NULL) { 668 role = NM_PIPE_ROLE_MASTER; 669 } else { 670 cbra = strrchr(hdr->nr_name, '}'); 671 if (cbra != NULL) { 672 role = NM_PIPE_ROLE_SLAVE; 673 } else { 674 nm_prdis("not a pipe"); 675 return 0; 676 } 677 } 678 pipe_id = cbra + 1; 679 if (*pipe_id == '\0' || cbra == hdr->nr_name) { 680 /* Bracket is the last character, so pipe name is missing; 681 * or bracket is the first character, so base port name 682 * is missing. */ 683 return EINVAL; 684 } 685 686 if (req->nr_mode != NR_REG_ALL_NIC && req->nr_mode != NR_REG_ONE_NIC) { 687 /* We only accept modes involving hardware rings. */ 688 return EINVAL; 689 } 690 691 /* first, try to find the parent adapter */ 692 for (;;) { 693 char nr_name_orig[NETMAP_REQ_IFNAMSIZ]; 694 int create_error; 695 696 /* Temporarily remove the pipe suffix. */ 697 strlcpy(nr_name_orig, hdr->nr_name, sizeof(nr_name_orig)); 698 *cbra = '\0'; 699 error = netmap_get_na(hdr, &pna, &ifp, nmd, create); 700 /* Restore the pipe suffix. */ 701 strlcpy(hdr->nr_name, nr_name_orig, sizeof(hdr->nr_name)); 702 if (!error) 703 break; 704 if (error != ENXIO || retries++) { 705 nm_prdis("parent lookup failed: %d", error); 706 return error; 707 } 708 nm_prdis("try to create a persistent vale port"); 709 /* create a persistent vale port and try again */ 710 *cbra = '\0'; 711 NMG_UNLOCK(); 712 create_error = netmap_vi_create(hdr, 1 /* autodelete */); 713 NMG_LOCK(); 714 strlcpy(hdr->nr_name, nr_name_orig, sizeof(hdr->nr_name)); 715 if (create_error && create_error != EEXIST) { 716 if (create_error != EOPNOTSUPP) { 717 nm_prerr("failed to create a persistent vale port: %d", 718 create_error); 719 } 720 return error; 721 } 722 } 723 724 if (NETMAP_OWNED_BY_KERN(pna)) { 725 nm_prdis("parent busy"); 726 error = EBUSY; 727 goto put_out; 728 } 729 730 /* next, lookup the pipe id in the parent list */ 731 reqna = NULL; 732 mna = netmap_pipe_find(pna, pipe_id); 733 if (mna) { 734 if (mna->role == role) { 735 nm_prdis("found %s directly at %d", pipe_id, mna->parent_slot); 736 reqna = mna; 737 } else { 738 nm_prdis("found %s indirectly at %d", pipe_id, mna->parent_slot); 739 reqna = mna->peer; 740 } 741 /* the pipe we have found already holds a ref to the parent, 742 * so we need to drop the one we got from netmap_get_na() 743 */ 744 netmap_unget_na(pna, ifp); 745 goto found; 746 } 747 nm_prdis("pipe %s not found, create %d", pipe_id, create); 748 if (!create) { 749 error = ENODEV; 750 goto put_out; 751 } 752 /* we create both master and slave. 753 * The endpoint we were asked for holds a reference to 754 * the other one. 755 */ 756 mna = nm_os_malloc(sizeof(*mna)); 757 if (mna == NULL) { 758 error = ENOMEM; 759 goto put_out; 760 } 761 snprintf(mna->up.name, sizeof(mna->up.name), "%s{%s", pna->name, pipe_id); 762 763 mna->role = NM_PIPE_ROLE_MASTER; 764 mna->parent = pna; 765 mna->parent_ifp = ifp; 766 767 mna->up.nm_txsync = netmap_pipe_txsync; 768 mna->up.nm_rxsync = netmap_pipe_rxsync; 769 mna->up.nm_register = netmap_pipe_reg; 770 mna->up.nm_dtor = netmap_pipe_dtor; 771 mna->up.nm_krings_create = netmap_pipe_krings_create; 772 mna->up.nm_krings_delete = netmap_pipe_krings_delete; 773 mna->up.nm_mem = netmap_mem_get(pna->nm_mem); 774 mna->up.na_flags |= NAF_MEM_OWNER; 775 mna->up.na_lut = pna->na_lut; 776 777 mna->up.num_tx_rings = req->nr_tx_rings; 778 nm_bound_var(&mna->up.num_tx_rings, 1, 779 1, NM_PIPE_MAXRINGS, NULL); 780 mna->up.num_rx_rings = req->nr_rx_rings; 781 nm_bound_var(&mna->up.num_rx_rings, 1, 782 1, NM_PIPE_MAXRINGS, NULL); 783 mna->up.num_tx_desc = req->nr_tx_slots; 784 nm_bound_var(&mna->up.num_tx_desc, pna->num_tx_desc, 785 1, NM_PIPE_MAXSLOTS, NULL); 786 mna->up.num_rx_desc = req->nr_rx_slots; 787 nm_bound_var(&mna->up.num_rx_desc, pna->num_rx_desc, 788 1, NM_PIPE_MAXSLOTS, NULL); 789 error = netmap_attach_common(&mna->up); 790 if (error) 791 goto free_mna; 792 /* register the master with the parent */ 793 error = netmap_pipe_add(pna, mna); 794 if (error) 795 goto free_mna; 796 797 /* create the slave */ 798 sna = nm_os_malloc(sizeof(*mna)); 799 if (sna == NULL) { 800 error = ENOMEM; 801 goto unregister_mna; 802 } 803 /* most fields are the same, copy from master and then fix */ 804 *sna = *mna; 805 sna->up.nm_mem = netmap_mem_get(mna->up.nm_mem); 806 /* swap the number of tx/rx rings and slots */ 807 sna->up.num_tx_rings = mna->up.num_rx_rings; 808 sna->up.num_tx_desc = mna->up.num_rx_desc; 809 sna->up.num_rx_rings = mna->up.num_tx_rings; 810 sna->up.num_rx_desc = mna->up.num_tx_desc; 811 snprintf(sna->up.name, sizeof(sna->up.name), "%s}%s", pna->name, pipe_id); 812 sna->role = NM_PIPE_ROLE_SLAVE; 813 error = netmap_attach_common(&sna->up); 814 if (error) 815 goto free_sna; 816 817 /* join the two endpoints */ 818 mna->peer = sna; 819 sna->peer = mna; 820 821 /* we already have a reference to the parent, but we 822 * need another one for the other endpoint we created 823 */ 824 netmap_adapter_get(pna); 825 /* likewise for the ifp, if any */ 826 if (ifp) 827 if_ref(ifp); 828 829 if (role == NM_PIPE_ROLE_MASTER) { 830 reqna = mna; 831 mna->peer_ref = 1; 832 netmap_adapter_get(&sna->up); 833 } else { 834 reqna = sna; 835 sna->peer_ref = 1; 836 netmap_adapter_get(&mna->up); 837 } 838 nm_prdis("created master %p and slave %p", mna, sna); 839found: 840 841 nm_prdis("pipe %s %s at %p", pipe_id, 842 (reqna->role == NM_PIPE_ROLE_MASTER ? "master" : "slave"), reqna); 843 *na = &reqna->up; 844 netmap_adapter_get(*na); 845 846 /* keep the reference to the parent. 847 * It will be released by the req destructor 848 */ 849 850 return 0; 851 852free_sna: 853 nm_os_free(sna); 854unregister_mna: 855 netmap_pipe_remove(pna, mna); 856free_mna: 857 nm_os_free(mna); 858put_out: 859 netmap_unget_na(pna, ifp); 860 return error; 861} 862 863 864#endif /* WITH_PIPES */ 865