1 /* 2 * linux/fs/9p/trans_fd.c 3 * 4 * Fd transport layer. Includes deprecated socket layer. 5 * 6 * Copyright (C) 2006 by Russ Cox <rsc@swtch.com> 7 * Copyright (C) 2004-2005 by Latchesar Ionkov <lucho@ionkov.net> 8 * Copyright (C) 2004-2008 by Eric Van Hensbergen <ericvh@gmail.com> 9 * Copyright (C) 1997-2002 by Ron Minnich <rminnich@sarnoff.com> 10 * 11 * This program is free software; you can redistribute it and/or modify 12 * it under the terms of the GNU General Public License version 2 13 * as published by the Free Software Foundation. 14 * 15 * This program is distributed in the hope that it will be useful, 16 * but WITHOUT ANY WARRANTY; without even the implied warranty of 17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 18 * GNU General Public License for more details. 19 * 20 * You should have received a copy of the GNU General Public License 21 * along with this program; if not, write to: 22 * Free Software Foundation 23 * 51 Franklin Street, Fifth Floor 24 * Boston, MA 02111-1301 USA 25 * 26 */ 27 28 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 29 30 #include <linux/in.h> 31 #include <linux/module.h> 32 #include <linux/net.h> 33 #include <linux/ipv6.h> 34 #include <linux/kthread.h> 35 #include <linux/errno.h> 36 #include <linux/kernel.h> 37 #include <linux/un.h> 38 #include <linux/uaccess.h> 39 #include <linux/inet.h> 40 #include <linux/idr.h> 41 #include <linux/file.h> 42 #include <linux/parser.h> 43 #include <linux/slab.h> 44 #include <linux/seq_file.h> 45 #include <net/9p/9p.h> 46 #include <net/9p/client.h> 47 #include <net/9p/transport.h> 48 49 #include <linux/syscalls.h> /* killme */ 50 51 #define P9_PORT 564 52 #define MAX_SOCK_BUF (64*1024) 53 #define MAXPOLLWADDR 2 54 55 static struct p9_trans_module p9_tcp_trans; 56 static struct p9_trans_module p9_fd_trans; 57 58 /** 59 * struct p9_fd_opts - per-transport options 60 * @rfd: file descriptor for reading (trans=fd) 61 * @wfd: file descriptor for writing (trans=fd) 62 * @port: port to connect to (trans=tcp) 63 * 64 */ 65 66 struct p9_fd_opts { 67 int rfd; 68 int wfd; 69 u16 port; 70 bool privport; 71 }; 72 73 /* 74 * Option Parsing (code inspired by NFS code) 75 * - a little lazy - parse all fd-transport options 76 */ 77 78 enum { 79 /* Options that take integer arguments */ 80 Opt_port, Opt_rfdno, Opt_wfdno, Opt_err, 81 /* Options that take no arguments */ 82 Opt_privport, 83 }; 84 85 static const match_table_t tokens = { 86 {Opt_port, "port=%u"}, 87 {Opt_rfdno, "rfdno=%u"}, 88 {Opt_wfdno, "wfdno=%u"}, 89 {Opt_privport, "privport"}, 90 {Opt_err, NULL}, 91 }; 92 93 enum { 94 Rworksched = 1, /* read work scheduled or running */ 95 Rpending = 2, /* can read */ 96 Wworksched = 4, /* write work scheduled or running */ 97 Wpending = 8, /* can write */ 98 }; 99 100 struct p9_poll_wait { 101 struct p9_conn *conn; 102 wait_queue_entry_t wait; 103 wait_queue_head_t *wait_addr; 104 }; 105 106 /** 107 * struct p9_conn - fd mux connection state information 108 * @mux_list: list link for mux to manage multiple connections (?) 109 * @client: reference to client instance for this connection 110 * @err: error state 111 * @req_list: accounting for requests which have been sent 112 * @unsent_req_list: accounting for requests that haven't been sent 113 * @req: current request being processed (if any) 114 * @tmp_buf: temporary buffer to read in header 115 * @rc: temporary fcall for reading current frame 116 * @wpos: write position for current frame 117 * @wsize: amount of data to write for current frame 118 * @wbuf: current write buffer 119 * @poll_pending_link: pending links to be polled per conn 120 * @poll_wait: array of wait_q's for various worker threads 121 * @pt: poll state 122 * @rq: current read work 123 * @wq: current write work 124 * @wsched: ???? 125 * 126 */ 127 128 struct p9_conn { 129 struct list_head mux_list; 130 struct p9_client *client; 131 int err; 132 struct list_head req_list; 133 struct list_head unsent_req_list; 134 struct p9_req_t *rreq; 135 struct p9_req_t *wreq; 136 char tmp_buf[7]; 137 struct p9_fcall rc; 138 int wpos; 139 int wsize; 140 char *wbuf; 141 struct list_head poll_pending_link; 142 struct p9_poll_wait poll_wait[MAXPOLLWADDR]; 143 poll_table pt; 144 struct work_struct rq; 145 struct work_struct wq; 146 unsigned long wsched; 147 }; 148 149 /** 150 * struct p9_trans_fd - transport state 151 * @rd: reference to file to read from 152 * @wr: reference of file to write to 153 * @conn: connection state reference 154 * 155 */ 156 157 struct p9_trans_fd { 158 struct file *rd; 159 struct file *wr; 160 struct p9_conn conn; 161 }; 162 163 static void p9_poll_workfn(struct work_struct *work); 164 165 static DEFINE_SPINLOCK(p9_poll_lock); 166 static LIST_HEAD(p9_poll_pending_list); 167 static DECLARE_WORK(p9_poll_work, p9_poll_workfn); 168 169 static unsigned int p9_ipport_resv_min = P9_DEF_MIN_RESVPORT; 170 static unsigned int p9_ipport_resv_max = P9_DEF_MAX_RESVPORT; 171 172 static void p9_mux_poll_stop(struct p9_conn *m) 173 { 174 unsigned long flags; 175 int i; 176 177 for (i = 0; i < ARRAY_SIZE(m->poll_wait); i++) { 178 struct p9_poll_wait *pwait = &m->poll_wait[i]; 179 180 if (pwait->wait_addr) { 181 remove_wait_queue(pwait->wait_addr, &pwait->wait); 182 pwait->wait_addr = NULL; 183 } 184 } 185 186 spin_lock_irqsave(&p9_poll_lock, flags); 187 list_del_init(&m->poll_pending_link); 188 spin_unlock_irqrestore(&p9_poll_lock, flags); 189 190 flush_work(&p9_poll_work); 191 } 192 193 /** 194 * p9_conn_cancel - cancel all pending requests with error 195 * @m: mux data 196 * @err: error code 197 * 198 */ 199 200 static void p9_conn_cancel(struct p9_conn *m, int err) 201 { 202 struct p9_req_t *req, *rtmp; 203 LIST_HEAD(cancel_list); 204 205 p9_debug(P9_DEBUG_ERROR, "mux %p err %d\n", m, err); 206 207 spin_lock(&m->client->lock); 208 209 if (m->err) { 210 spin_unlock(&m->client->lock); 211 return; 212 } 213 214 m->err = err; 215 216 list_for_each_entry_safe(req, rtmp, &m->req_list, req_list) { 217 list_move(&req->req_list, &cancel_list); 218 } 219 list_for_each_entry_safe(req, rtmp, &m->unsent_req_list, req_list) { 220 list_move(&req->req_list, &cancel_list); 221 } 222 223 list_for_each_entry_safe(req, rtmp, &cancel_list, req_list) { 224 p9_debug(P9_DEBUG_ERROR, "call back req %p\n", req); 225 list_del(&req->req_list); 226 if (!req->t_err) 227 req->t_err = err; 228 p9_client_cb(m->client, req, REQ_STATUS_ERROR); 229 } 230 spin_unlock(&m->client->lock); 231 } 232 233 static __poll_t 234 p9_fd_poll(struct p9_client *client, struct poll_table_struct *pt, int *err) 235 { 236 __poll_t ret; 237 struct p9_trans_fd *ts = NULL; 238 239 if (client && client->status == Connected) 240 ts = client->trans; 241 242 if (!ts) { 243 if (err) 244 *err = -EREMOTEIO; 245 return EPOLLERR; 246 } 247 248 ret = vfs_poll(ts->rd, pt); 249 if (ts->rd != ts->wr) 250 ret = (ret & ~EPOLLOUT) | (vfs_poll(ts->wr, pt) & ~EPOLLIN); 251 return ret; 252 } 253 254 /** 255 * p9_fd_read- read from a fd 256 * @client: client instance 257 * @v: buffer to receive data into 258 * @len: size of receive buffer 259 * 260 */ 261 262 static int p9_fd_read(struct p9_client *client, void *v, int len) 263 { 264 int ret; 265 struct p9_trans_fd *ts = NULL; 266 loff_t pos; 267 268 if (client && client->status != Disconnected) 269 ts = client->trans; 270 271 if (!ts) 272 return -EREMOTEIO; 273 274 if (!(ts->rd->f_flags & O_NONBLOCK)) 275 p9_debug(P9_DEBUG_ERROR, "blocking read ...\n"); 276 277 pos = ts->rd->f_pos; 278 ret = kernel_read(ts->rd, v, len, &pos); 279 if (ret <= 0 && ret != -ERESTARTSYS && ret != -EAGAIN) 280 client->status = Disconnected; 281 return ret; 282 } 283 284 /** 285 * p9_read_work - called when there is some data to be read from a transport 286 * @work: container of work to be done 287 * 288 */ 289 290 static void p9_read_work(struct work_struct *work) 291 { 292 __poll_t n; 293 int err; 294 struct p9_conn *m; 295 296 m = container_of(work, struct p9_conn, rq); 297 298 if (m->err < 0) 299 return; 300 301 p9_debug(P9_DEBUG_TRANS, "start mux %p pos %zd\n", m, m->rc.offset); 302 303 if (!m->rc.sdata) { 304 m->rc.sdata = m->tmp_buf; 305 m->rc.offset = 0; 306 m->rc.capacity = 7; /* start by reading header */ 307 } 308 309 clear_bit(Rpending, &m->wsched); 310 p9_debug(P9_DEBUG_TRANS, "read mux %p pos %zd size: %zd = %zd\n", 311 m, m->rc.offset, m->rc.capacity, 312 m->rc.capacity - m->rc.offset); 313 err = p9_fd_read(m->client, m->rc.sdata + m->rc.offset, 314 m->rc.capacity - m->rc.offset); 315 p9_debug(P9_DEBUG_TRANS, "mux %p got %d bytes\n", m, err); 316 if (err == -EAGAIN) 317 goto end_clear; 318 319 if (err <= 0) 320 goto error; 321 322 m->rc.offset += err; 323 324 /* header read in */ 325 if ((!m->rreq) && (m->rc.offset == m->rc.capacity)) { 326 p9_debug(P9_DEBUG_TRANS, "got new header\n"); 327 328 /* Header size */ 329 m->rc.size = 7; 330 err = p9_parse_header(&m->rc, &m->rc.size, NULL, NULL, 0); 331 if (err) { 332 p9_debug(P9_DEBUG_ERROR, 333 "error parsing header: %d\n", err); 334 goto error; 335 } 336 337 if (m->rc.size >= m->client->msize) { 338 p9_debug(P9_DEBUG_ERROR, 339 "requested packet size too big: %d\n", 340 m->rc.size); 341 err = -EIO; 342 goto error; 343 } 344 345 p9_debug(P9_DEBUG_TRANS, 346 "mux %p pkt: size: %d bytes tag: %d\n", 347 m, m->rc.size, m->rc.tag); 348 349 m->rreq = p9_tag_lookup(m->client, m->rc.tag); 350 if (!m->rreq || (m->rreq->status != REQ_STATUS_SENT)) { 351 p9_debug(P9_DEBUG_ERROR, "Unexpected packet tag %d\n", 352 m->rc.tag); 353 err = -EIO; 354 goto error; 355 } 356 357 if (!m->rreq->rc.sdata) { 358 p9_debug(P9_DEBUG_ERROR, 359 "No recv fcall for tag %d (req %p), disconnecting!\n", 360 m->rc.tag, m->rreq); 361 m->rreq = NULL; 362 err = -EIO; 363 goto error; 364 } 365 m->rc.sdata = m->rreq->rc.sdata; 366 memcpy(m->rc.sdata, m->tmp_buf, m->rc.capacity); 367 m->rc.capacity = m->rc.size; 368 } 369 370 /* packet is read in 371 * not an else because some packets (like clunk) have no payload 372 */ 373 if ((m->rreq) && (m->rc.offset == m->rc.capacity)) { 374 p9_debug(P9_DEBUG_TRANS, "got new packet\n"); 375 m->rreq->rc.size = m->rc.offset; 376 spin_lock(&m->client->lock); 377 if (m->rreq->status == REQ_STATUS_SENT) { 378 list_del(&m->rreq->req_list); 379 p9_client_cb(m->client, m->rreq, REQ_STATUS_RCVD); 380 } else { 381 spin_unlock(&m->client->lock); 382 p9_debug(P9_DEBUG_ERROR, 383 "Request tag %d errored out while we were reading the reply\n", 384 m->rc.tag); 385 err = -EIO; 386 goto error; 387 } 388 spin_unlock(&m->client->lock); 389 m->rc.sdata = NULL; 390 m->rc.offset = 0; 391 m->rc.capacity = 0; 392 p9_req_put(m->rreq); 393 m->rreq = NULL; 394 } 395 396 end_clear: 397 clear_bit(Rworksched, &m->wsched); 398 399 if (!list_empty(&m->req_list)) { 400 if (test_and_clear_bit(Rpending, &m->wsched)) 401 n = EPOLLIN; 402 else 403 n = p9_fd_poll(m->client, NULL, NULL); 404 405 if ((n & EPOLLIN) && !test_and_set_bit(Rworksched, &m->wsched)) { 406 p9_debug(P9_DEBUG_TRANS, "sched read work %p\n", m); 407 schedule_work(&m->rq); 408 } 409 } 410 411 return; 412 error: 413 p9_conn_cancel(m, err); 414 clear_bit(Rworksched, &m->wsched); 415 } 416 417 /** 418 * p9_fd_write - write to a socket 419 * @client: client instance 420 * @v: buffer to send data from 421 * @len: size of send buffer 422 * 423 */ 424 425 static int p9_fd_write(struct p9_client *client, void *v, int len) 426 { 427 ssize_t ret; 428 struct p9_trans_fd *ts = NULL; 429 430 if (client && client->status != Disconnected) 431 ts = client->trans; 432 433 if (!ts) 434 return -EREMOTEIO; 435 436 if (!(ts->wr->f_flags & O_NONBLOCK)) 437 p9_debug(P9_DEBUG_ERROR, "blocking write ...\n"); 438 439 ret = kernel_write(ts->wr, v, len, &ts->wr->f_pos); 440 if (ret <= 0 && ret != -ERESTARTSYS && ret != -EAGAIN) 441 client->status = Disconnected; 442 return ret; 443 } 444 445 /** 446 * p9_write_work - called when a transport can send some data 447 * @work: container for work to be done 448 * 449 */ 450 451 static void p9_write_work(struct work_struct *work) 452 { 453 __poll_t n; 454 int err; 455 struct p9_conn *m; 456 struct p9_req_t *req; 457 458 m = container_of(work, struct p9_conn, wq); 459 460 if (m->err < 0) { 461 clear_bit(Wworksched, &m->wsched); 462 return; 463 } 464 465 if (!m->wsize) { 466 spin_lock(&m->client->lock); 467 if (list_empty(&m->unsent_req_list)) { 468 clear_bit(Wworksched, &m->wsched); 469 spin_unlock(&m->client->lock); 470 return; 471 } 472 473 req = list_entry(m->unsent_req_list.next, struct p9_req_t, 474 req_list); 475 req->status = REQ_STATUS_SENT; 476 p9_debug(P9_DEBUG_TRANS, "move req %p\n", req); 477 list_move_tail(&req->req_list, &m->req_list); 478 479 m->wbuf = req->tc.sdata; 480 m->wsize = req->tc.size; 481 m->wpos = 0; 482 p9_req_get(req); 483 m->wreq = req; 484 spin_unlock(&m->client->lock); 485 } 486 487 p9_debug(P9_DEBUG_TRANS, "mux %p pos %d size %d\n", 488 m, m->wpos, m->wsize); 489 clear_bit(Wpending, &m->wsched); 490 err = p9_fd_write(m->client, m->wbuf + m->wpos, m->wsize - m->wpos); 491 p9_debug(P9_DEBUG_TRANS, "mux %p sent %d bytes\n", m, err); 492 if (err == -EAGAIN) 493 goto end_clear; 494 495 496 if (err < 0) 497 goto error; 498 else if (err == 0) { 499 err = -EREMOTEIO; 500 goto error; 501 } 502 503 m->wpos += err; 504 if (m->wpos == m->wsize) { 505 m->wpos = m->wsize = 0; 506 p9_req_put(m->wreq); 507 m->wreq = NULL; 508 } 509 510 end_clear: 511 clear_bit(Wworksched, &m->wsched); 512 513 if (m->wsize || !list_empty(&m->unsent_req_list)) { 514 if (test_and_clear_bit(Wpending, &m->wsched)) 515 n = EPOLLOUT; 516 else 517 n = p9_fd_poll(m->client, NULL, NULL); 518 519 if ((n & EPOLLOUT) && 520 !test_and_set_bit(Wworksched, &m->wsched)) { 521 p9_debug(P9_DEBUG_TRANS, "sched write work %p\n", m); 522 schedule_work(&m->wq); 523 } 524 } 525 526 return; 527 528 error: 529 p9_conn_cancel(m, err); 530 clear_bit(Wworksched, &m->wsched); 531 } 532 533 static int p9_pollwake(wait_queue_entry_t *wait, unsigned int mode, int sync, void *key) 534 { 535 struct p9_poll_wait *pwait = 536 container_of(wait, struct p9_poll_wait, wait); 537 struct p9_conn *m = pwait->conn; 538 unsigned long flags; 539 540 spin_lock_irqsave(&p9_poll_lock, flags); 541 if (list_empty(&m->poll_pending_link)) 542 list_add_tail(&m->poll_pending_link, &p9_poll_pending_list); 543 spin_unlock_irqrestore(&p9_poll_lock, flags); 544 545 schedule_work(&p9_poll_work); 546 return 1; 547 } 548 549 /** 550 * p9_pollwait - add poll task to the wait queue 551 * @filp: file pointer being polled 552 * @wait_address: wait_q to block on 553 * @p: poll state 554 * 555 * called by files poll operation to add v9fs-poll task to files wait queue 556 */ 557 558 static void 559 p9_pollwait(struct file *filp, wait_queue_head_t *wait_address, poll_table *p) 560 { 561 struct p9_conn *m = container_of(p, struct p9_conn, pt); 562 struct p9_poll_wait *pwait = NULL; 563 int i; 564 565 for (i = 0; i < ARRAY_SIZE(m->poll_wait); i++) { 566 if (m->poll_wait[i].wait_addr == NULL) { 567 pwait = &m->poll_wait[i]; 568 break; 569 } 570 } 571 572 if (!pwait) { 573 p9_debug(P9_DEBUG_ERROR, "not enough wait_address slots\n"); 574 return; 575 } 576 577 pwait->conn = m; 578 pwait->wait_addr = wait_address; 579 init_waitqueue_func_entry(&pwait->wait, p9_pollwake); 580 add_wait_queue(wait_address, &pwait->wait); 581 } 582 583 /** 584 * p9_conn_create - initialize the per-session mux data 585 * @client: client instance 586 * 587 * Note: Creates the polling task if this is the first session. 588 */ 589 590 static void p9_conn_create(struct p9_client *client) 591 { 592 __poll_t n; 593 struct p9_trans_fd *ts = client->trans; 594 struct p9_conn *m = &ts->conn; 595 596 p9_debug(P9_DEBUG_TRANS, "client %p msize %d\n", client, client->msize); 597 598 INIT_LIST_HEAD(&m->mux_list); 599 m->client = client; 600 601 INIT_LIST_HEAD(&m->req_list); 602 INIT_LIST_HEAD(&m->unsent_req_list); 603 INIT_WORK(&m->rq, p9_read_work); 604 INIT_WORK(&m->wq, p9_write_work); 605 INIT_LIST_HEAD(&m->poll_pending_link); 606 init_poll_funcptr(&m->pt, p9_pollwait); 607 608 n = p9_fd_poll(client, &m->pt, NULL); 609 if (n & EPOLLIN) { 610 p9_debug(P9_DEBUG_TRANS, "mux %p can read\n", m); 611 set_bit(Rpending, &m->wsched); 612 } 613 614 if (n & EPOLLOUT) { 615 p9_debug(P9_DEBUG_TRANS, "mux %p can write\n", m); 616 set_bit(Wpending, &m->wsched); 617 } 618 } 619 620 /** 621 * p9_poll_mux - polls a mux and schedules read or write works if necessary 622 * @m: connection to poll 623 * 624 */ 625 626 static void p9_poll_mux(struct p9_conn *m) 627 { 628 __poll_t n; 629 int err = -ECONNRESET; 630 631 if (m->err < 0) 632 return; 633 634 n = p9_fd_poll(m->client, NULL, &err); 635 if (n & (EPOLLERR | EPOLLHUP | EPOLLNVAL)) { 636 p9_debug(P9_DEBUG_TRANS, "error mux %p err %d\n", m, n); 637 p9_conn_cancel(m, err); 638 } 639 640 if (n & EPOLLIN) { 641 set_bit(Rpending, &m->wsched); 642 p9_debug(P9_DEBUG_TRANS, "mux %p can read\n", m); 643 if (!test_and_set_bit(Rworksched, &m->wsched)) { 644 p9_debug(P9_DEBUG_TRANS, "sched read work %p\n", m); 645 schedule_work(&m->rq); 646 } 647 } 648 649 if (n & EPOLLOUT) { 650 set_bit(Wpending, &m->wsched); 651 p9_debug(P9_DEBUG_TRANS, "mux %p can write\n", m); 652 if ((m->wsize || !list_empty(&m->unsent_req_list)) && 653 !test_and_set_bit(Wworksched, &m->wsched)) { 654 p9_debug(P9_DEBUG_TRANS, "sched write work %p\n", m); 655 schedule_work(&m->wq); 656 } 657 } 658 } 659 660 /** 661 * p9_fd_request - send 9P request 662 * The function can sleep until the request is scheduled for sending. 663 * The function can be interrupted. Return from the function is not 664 * a guarantee that the request is sent successfully. 665 * 666 * @client: client instance 667 * @req: request to be sent 668 * 669 */ 670 671 static int p9_fd_request(struct p9_client *client, struct p9_req_t *req) 672 { 673 __poll_t n; 674 struct p9_trans_fd *ts = client->trans; 675 struct p9_conn *m = &ts->conn; 676 677 p9_debug(P9_DEBUG_TRANS, "mux %p task %p tcall %p id %d\n", 678 m, current, &req->tc, req->tc.id); 679 if (m->err < 0) 680 return m->err; 681 682 spin_lock(&client->lock); 683 req->status = REQ_STATUS_UNSENT; 684 list_add_tail(&req->req_list, &m->unsent_req_list); 685 spin_unlock(&client->lock); 686 687 if (test_and_clear_bit(Wpending, &m->wsched)) 688 n = EPOLLOUT; 689 else 690 n = p9_fd_poll(m->client, NULL, NULL); 691 692 if (n & EPOLLOUT && !test_and_set_bit(Wworksched, &m->wsched)) 693 schedule_work(&m->wq); 694 695 return 0; 696 } 697 698 static int p9_fd_cancel(struct p9_client *client, struct p9_req_t *req) 699 { 700 int ret = 1; 701 702 p9_debug(P9_DEBUG_TRANS, "client %p req %p\n", client, req); 703 704 spin_lock(&client->lock); 705 706 if (req->status == REQ_STATUS_UNSENT) { 707 list_del(&req->req_list); 708 req->status = REQ_STATUS_FLSHD; 709 p9_req_put(req); 710 ret = 0; 711 } 712 spin_unlock(&client->lock); 713 714 return ret; 715 } 716 717 static int p9_fd_cancelled(struct p9_client *client, struct p9_req_t *req) 718 { 719 p9_debug(P9_DEBUG_TRANS, "client %p req %p\n", client, req); 720 721 /* we haven't received a response for oldreq, 722 * remove it from the list. 723 */ 724 spin_lock(&client->lock); 725 list_del(&req->req_list); 726 spin_unlock(&client->lock); 727 p9_req_put(req); 728 729 return 0; 730 } 731 732 static int p9_fd_show_options(struct seq_file *m, struct p9_client *clnt) 733 { 734 if (clnt->trans_mod == &p9_tcp_trans) { 735 if (clnt->trans_opts.tcp.port != P9_PORT) 736 seq_printf(m, ",port=%u", clnt->trans_opts.tcp.port); 737 } else if (clnt->trans_mod == &p9_fd_trans) { 738 if (clnt->trans_opts.fd.rfd != ~0) 739 seq_printf(m, ",rfd=%u", clnt->trans_opts.fd.rfd); 740 if (clnt->trans_opts.fd.wfd != ~0) 741 seq_printf(m, ",wfd=%u", clnt->trans_opts.fd.wfd); 742 } 743 return 0; 744 } 745 746 /** 747 * parse_opts - parse mount options into p9_fd_opts structure 748 * @params: options string passed from mount 749 * @opts: fd transport-specific structure to parse options into 750 * 751 * Returns 0 upon success, -ERRNO upon failure 752 */ 753 754 static int parse_opts(char *params, struct p9_fd_opts *opts) 755 { 756 char *p; 757 substring_t args[MAX_OPT_ARGS]; 758 int option; 759 char *options, *tmp_options; 760 761 opts->port = P9_PORT; 762 opts->rfd = ~0; 763 opts->wfd = ~0; 764 opts->privport = false; 765 766 if (!params) 767 return 0; 768 769 tmp_options = kstrdup(params, GFP_KERNEL); 770 if (!tmp_options) { 771 p9_debug(P9_DEBUG_ERROR, 772 "failed to allocate copy of option string\n"); 773 return -ENOMEM; 774 } 775 options = tmp_options; 776 777 while ((p = strsep(&options, ",")) != NULL) { 778 int token; 779 int r; 780 if (!*p) 781 continue; 782 token = match_token(p, tokens, args); 783 if ((token != Opt_err) && (token != Opt_privport)) { 784 r = match_int(&args[0], &option); 785 if (r < 0) { 786 p9_debug(P9_DEBUG_ERROR, 787 "integer field, but no integer?\n"); 788 continue; 789 } 790 } 791 switch (token) { 792 case Opt_port: 793 opts->port = option; 794 break; 795 case Opt_rfdno: 796 opts->rfd = option; 797 break; 798 case Opt_wfdno: 799 opts->wfd = option; 800 break; 801 case Opt_privport: 802 opts->privport = true; 803 break; 804 default: 805 continue; 806 } 807 } 808 809 kfree(tmp_options); 810 return 0; 811 } 812 813 static int p9_fd_open(struct p9_client *client, int rfd, int wfd) 814 { 815 struct p9_trans_fd *ts = kzalloc(sizeof(struct p9_trans_fd), 816 GFP_KERNEL); 817 if (!ts) 818 return -ENOMEM; 819 820 ts->rd = fget(rfd); 821 ts->wr = fget(wfd); 822 if (!ts->rd || !ts->wr) { 823 if (ts->rd) 824 fput(ts->rd); 825 if (ts->wr) 826 fput(ts->wr); 827 kfree(ts); 828 return -EIO; 829 } 830 831 client->trans = ts; 832 client->status = Connected; 833 834 return 0; 835 } 836 837 static int p9_socket_open(struct p9_client *client, struct socket *csocket) 838 { 839 struct p9_trans_fd *p; 840 struct file *file; 841 842 p = kzalloc(sizeof(struct p9_trans_fd), GFP_KERNEL); 843 if (!p) 844 return -ENOMEM; 845 846 csocket->sk->sk_allocation = GFP_NOIO; 847 file = sock_alloc_file(csocket, 0, NULL); 848 if (IS_ERR(file)) { 849 pr_err("%s (%d): failed to map fd\n", 850 __func__, task_pid_nr(current)); 851 kfree(p); 852 return PTR_ERR(file); 853 } 854 855 get_file(file); 856 p->wr = p->rd = file; 857 client->trans = p; 858 client->status = Connected; 859 860 p->rd->f_flags |= O_NONBLOCK; 861 862 p9_conn_create(client); 863 return 0; 864 } 865 866 /** 867 * p9_mux_destroy - cancels all pending requests of mux 868 * @m: mux to destroy 869 * 870 */ 871 872 static void p9_conn_destroy(struct p9_conn *m) 873 { 874 p9_debug(P9_DEBUG_TRANS, "mux %p prev %p next %p\n", 875 m, m->mux_list.prev, m->mux_list.next); 876 877 p9_mux_poll_stop(m); 878 cancel_work_sync(&m->rq); 879 if (m->rreq) { 880 p9_req_put(m->rreq); 881 m->rreq = NULL; 882 } 883 cancel_work_sync(&m->wq); 884 if (m->wreq) { 885 p9_req_put(m->wreq); 886 m->wreq = NULL; 887 } 888 889 p9_conn_cancel(m, -ECONNRESET); 890 891 m->client = NULL; 892 } 893 894 /** 895 * p9_fd_close - shutdown file descriptor transport 896 * @client: client instance 897 * 898 */ 899 900 static void p9_fd_close(struct p9_client *client) 901 { 902 struct p9_trans_fd *ts; 903 904 if (!client) 905 return; 906 907 ts = client->trans; 908 if (!ts) 909 return; 910 911 client->status = Disconnected; 912 913 p9_conn_destroy(&ts->conn); 914 915 if (ts->rd) 916 fput(ts->rd); 917 if (ts->wr) 918 fput(ts->wr); 919 920 kfree(ts); 921 } 922 923 /* 924 * stolen from NFS - maybe should be made a generic function? 925 */ 926 static inline int valid_ipaddr4(const char *buf) 927 { 928 int rc, count, in[4]; 929 930 rc = sscanf(buf, "%d.%d.%d.%d", &in[0], &in[1], &in[2], &in[3]); 931 if (rc != 4) 932 return -EINVAL; 933 for (count = 0; count < 4; count++) { 934 if (in[count] > 255) 935 return -EINVAL; 936 } 937 return 0; 938 } 939 940 static int p9_bind_privport(struct socket *sock) 941 { 942 struct sockaddr_in cl; 943 int port, err = -EINVAL; 944 945 memset(&cl, 0, sizeof(cl)); 946 cl.sin_family = AF_INET; 947 cl.sin_addr.s_addr = INADDR_ANY; 948 for (port = p9_ipport_resv_max; port >= p9_ipport_resv_min; port--) { 949 cl.sin_port = htons((ushort)port); 950 err = kernel_bind(sock, (struct sockaddr *)&cl, sizeof(cl)); 951 if (err != -EADDRINUSE) 952 break; 953 } 954 return err; 955 } 956 957 958 static int 959 p9_fd_create_tcp(struct p9_client *client, const char *addr, char *args) 960 { 961 int err; 962 struct socket *csocket; 963 struct sockaddr_in sin_server; 964 struct p9_fd_opts opts; 965 966 err = parse_opts(args, &opts); 967 if (err < 0) 968 return err; 969 970 if (addr == NULL || valid_ipaddr4(addr) < 0) 971 return -EINVAL; 972 973 csocket = NULL; 974 975 client->trans_opts.tcp.port = opts.port; 976 client->trans_opts.tcp.privport = opts.privport; 977 sin_server.sin_family = AF_INET; 978 sin_server.sin_addr.s_addr = in_aton(addr); 979 sin_server.sin_port = htons(opts.port); 980 err = __sock_create(current->nsproxy->net_ns, PF_INET, 981 SOCK_STREAM, IPPROTO_TCP, &csocket, 1); 982 if (err) { 983 pr_err("%s (%d): problem creating socket\n", 984 __func__, task_pid_nr(current)); 985 return err; 986 } 987 988 if (opts.privport) { 989 err = p9_bind_privport(csocket); 990 if (err < 0) { 991 pr_err("%s (%d): problem binding to privport\n", 992 __func__, task_pid_nr(current)); 993 sock_release(csocket); 994 return err; 995 } 996 } 997 998 err = csocket->ops->connect(csocket, 999 (struct sockaddr *)&sin_server, 1000 sizeof(struct sockaddr_in), 0); 1001 if (err < 0) { 1002 pr_err("%s (%d): problem connecting socket to %s\n", 1003 __func__, task_pid_nr(current), addr); 1004 sock_release(csocket); 1005 return err; 1006 } 1007 1008 return p9_socket_open(client, csocket); 1009 } 1010 1011 static int 1012 p9_fd_create_unix(struct p9_client *client, const char *addr, char *args) 1013 { 1014 int err; 1015 struct socket *csocket; 1016 struct sockaddr_un sun_server; 1017 1018 csocket = NULL; 1019 1020 if (addr == NULL) 1021 return -EINVAL; 1022 1023 if (strlen(addr) >= UNIX_PATH_MAX) { 1024 pr_err("%s (%d): address too long: %s\n", 1025 __func__, task_pid_nr(current), addr); 1026 return -ENAMETOOLONG; 1027 } 1028 1029 sun_server.sun_family = PF_UNIX; 1030 strcpy(sun_server.sun_path, addr); 1031 err = __sock_create(current->nsproxy->net_ns, PF_UNIX, 1032 SOCK_STREAM, 0, &csocket, 1); 1033 if (err < 0) { 1034 pr_err("%s (%d): problem creating socket\n", 1035 __func__, task_pid_nr(current)); 1036 1037 return err; 1038 } 1039 err = csocket->ops->connect(csocket, (struct sockaddr *)&sun_server, 1040 sizeof(struct sockaddr_un) - 1, 0); 1041 if (err < 0) { 1042 pr_err("%s (%d): problem connecting socket: %s: %d\n", 1043 __func__, task_pid_nr(current), addr, err); 1044 sock_release(csocket); 1045 return err; 1046 } 1047 1048 return p9_socket_open(client, csocket); 1049 } 1050 1051 static int 1052 p9_fd_create(struct p9_client *client, const char *addr, char *args) 1053 { 1054 int err; 1055 struct p9_fd_opts opts; 1056 1057 parse_opts(args, &opts); 1058 client->trans_opts.fd.rfd = opts.rfd; 1059 client->trans_opts.fd.wfd = opts.wfd; 1060 1061 if (opts.rfd == ~0 || opts.wfd == ~0) { 1062 pr_err("Insufficient options for proto=fd\n"); 1063 return -ENOPROTOOPT; 1064 } 1065 1066 err = p9_fd_open(client, opts.rfd, opts.wfd); 1067 if (err < 0) 1068 return err; 1069 1070 p9_conn_create(client); 1071 1072 return 0; 1073 } 1074 1075 static struct p9_trans_module p9_tcp_trans = { 1076 .name = "tcp", 1077 .maxsize = MAX_SOCK_BUF, 1078 .def = 0, 1079 .create = p9_fd_create_tcp, 1080 .close = p9_fd_close, 1081 .request = p9_fd_request, 1082 .cancel = p9_fd_cancel, 1083 .cancelled = p9_fd_cancelled, 1084 .show_options = p9_fd_show_options, 1085 .owner = THIS_MODULE, 1086 }; 1087 1088 static struct p9_trans_module p9_unix_trans = { 1089 .name = "unix", 1090 .maxsize = MAX_SOCK_BUF, 1091 .def = 0, 1092 .create = p9_fd_create_unix, 1093 .close = p9_fd_close, 1094 .request = p9_fd_request, 1095 .cancel = p9_fd_cancel, 1096 .cancelled = p9_fd_cancelled, 1097 .show_options = p9_fd_show_options, 1098 .owner = THIS_MODULE, 1099 }; 1100 1101 static struct p9_trans_module p9_fd_trans = { 1102 .name = "fd", 1103 .maxsize = MAX_SOCK_BUF, 1104 .def = 0, 1105 .create = p9_fd_create, 1106 .close = p9_fd_close, 1107 .request = p9_fd_request, 1108 .cancel = p9_fd_cancel, 1109 .cancelled = p9_fd_cancelled, 1110 .show_options = p9_fd_show_options, 1111 .owner = THIS_MODULE, 1112 }; 1113 1114 /** 1115 * p9_poll_workfn - poll worker thread 1116 * @work: work queue 1117 * 1118 * polls all v9fs transports for new events and queues the appropriate 1119 * work to the work queue 1120 * 1121 */ 1122 1123 static void p9_poll_workfn(struct work_struct *work) 1124 { 1125 unsigned long flags; 1126 1127 p9_debug(P9_DEBUG_TRANS, "start %p\n", current); 1128 1129 spin_lock_irqsave(&p9_poll_lock, flags); 1130 while (!list_empty(&p9_poll_pending_list)) { 1131 struct p9_conn *conn = list_first_entry(&p9_poll_pending_list, 1132 struct p9_conn, 1133 poll_pending_link); 1134 list_del_init(&conn->poll_pending_link); 1135 spin_unlock_irqrestore(&p9_poll_lock, flags); 1136 1137 p9_poll_mux(conn); 1138 1139 spin_lock_irqsave(&p9_poll_lock, flags); 1140 } 1141 spin_unlock_irqrestore(&p9_poll_lock, flags); 1142 1143 p9_debug(P9_DEBUG_TRANS, "finish\n"); 1144 } 1145 1146 int p9_trans_fd_init(void) 1147 { 1148 v9fs_register_trans(&p9_tcp_trans); 1149 v9fs_register_trans(&p9_unix_trans); 1150 v9fs_register_trans(&p9_fd_trans); 1151 1152 return 0; 1153 } 1154 1155 void p9_trans_fd_exit(void) 1156 { 1157 flush_work(&p9_poll_work); 1158 v9fs_unregister_trans(&p9_tcp_trans); 1159 v9fs_unregister_trans(&p9_unix_trans); 1160 v9fs_unregister_trans(&p9_fd_trans); 1161 } 1162