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 <net/9p/9p.h> 45 #include <net/9p/client.h> 46 #include <net/9p/transport.h> 47 48 #include <linux/syscalls.h> /* killme */ 49 50 #define P9_PORT 564 51 #define MAX_SOCK_BUF (64*1024) 52 #define MAXPOLLWADDR 2 53 54 /** 55 * struct p9_fd_opts - per-transport options 56 * @rfd: file descriptor for reading (trans=fd) 57 * @wfd: file descriptor for writing (trans=fd) 58 * @port: port to connect to (trans=tcp) 59 * 60 */ 61 62 struct p9_fd_opts { 63 int rfd; 64 int wfd; 65 u16 port; 66 int privport; 67 }; 68 69 /* 70 * Option Parsing (code inspired by NFS code) 71 * - a little lazy - parse all fd-transport options 72 */ 73 74 enum { 75 /* Options that take integer arguments */ 76 Opt_port, Opt_rfdno, Opt_wfdno, Opt_err, 77 /* Options that take no arguments */ 78 Opt_privport, 79 }; 80 81 static const match_table_t tokens = { 82 {Opt_port, "port=%u"}, 83 {Opt_rfdno, "rfdno=%u"}, 84 {Opt_wfdno, "wfdno=%u"}, 85 {Opt_privport, "privport"}, 86 {Opt_err, NULL}, 87 }; 88 89 enum { 90 Rworksched = 1, /* read work scheduled or running */ 91 Rpending = 2, /* can read */ 92 Wworksched = 4, /* write work scheduled or running */ 93 Wpending = 8, /* can write */ 94 }; 95 96 struct p9_poll_wait { 97 struct p9_conn *conn; 98 wait_queue_t wait; 99 wait_queue_head_t *wait_addr; 100 }; 101 102 /** 103 * struct p9_conn - fd mux connection state information 104 * @mux_list: list link for mux to manage multiple connections (?) 105 * @client: reference to client instance for this connection 106 * @err: error state 107 * @req_list: accounting for requests which have been sent 108 * @unsent_req_list: accounting for requests that haven't been sent 109 * @req: current request being processed (if any) 110 * @tmp_buf: temporary buffer to read in header 111 * @rc: temporary fcall for reading current frame 112 * @wpos: write position for current frame 113 * @wsize: amount of data to write for current frame 114 * @wbuf: current write buffer 115 * @poll_pending_link: pending links to be polled per conn 116 * @poll_wait: array of wait_q's for various worker threads 117 * @pt: poll state 118 * @rq: current read work 119 * @wq: current write work 120 * @wsched: ???? 121 * 122 */ 123 124 struct p9_conn { 125 struct list_head mux_list; 126 struct p9_client *client; 127 int err; 128 struct list_head req_list; 129 struct list_head unsent_req_list; 130 struct p9_req_t *req; 131 char tmp_buf[7]; 132 struct p9_fcall rc; 133 int wpos; 134 int wsize; 135 char *wbuf; 136 struct list_head poll_pending_link; 137 struct p9_poll_wait poll_wait[MAXPOLLWADDR]; 138 poll_table pt; 139 struct work_struct rq; 140 struct work_struct wq; 141 unsigned long wsched; 142 }; 143 144 /** 145 * struct p9_trans_fd - transport state 146 * @rd: reference to file to read from 147 * @wr: reference of file to write to 148 * @conn: connection state reference 149 * 150 */ 151 152 struct p9_trans_fd { 153 struct file *rd; 154 struct file *wr; 155 struct p9_conn conn; 156 }; 157 158 static void p9_poll_workfn(struct work_struct *work); 159 160 static DEFINE_SPINLOCK(p9_poll_lock); 161 static LIST_HEAD(p9_poll_pending_list); 162 static DECLARE_WORK(p9_poll_work, p9_poll_workfn); 163 164 static unsigned int p9_ipport_resv_min = P9_DEF_MIN_RESVPORT; 165 static unsigned int p9_ipport_resv_max = P9_DEF_MAX_RESVPORT; 166 167 static void p9_mux_poll_stop(struct p9_conn *m) 168 { 169 unsigned long flags; 170 int i; 171 172 for (i = 0; i < ARRAY_SIZE(m->poll_wait); i++) { 173 struct p9_poll_wait *pwait = &m->poll_wait[i]; 174 175 if (pwait->wait_addr) { 176 remove_wait_queue(pwait->wait_addr, &pwait->wait); 177 pwait->wait_addr = NULL; 178 } 179 } 180 181 spin_lock_irqsave(&p9_poll_lock, flags); 182 list_del_init(&m->poll_pending_link); 183 spin_unlock_irqrestore(&p9_poll_lock, flags); 184 } 185 186 /** 187 * p9_conn_cancel - cancel all pending requests with error 188 * @m: mux data 189 * @err: error code 190 * 191 */ 192 193 static void p9_conn_cancel(struct p9_conn *m, int err) 194 { 195 struct p9_req_t *req, *rtmp; 196 unsigned long flags; 197 LIST_HEAD(cancel_list); 198 199 p9_debug(P9_DEBUG_ERROR, "mux %p err %d\n", m, err); 200 201 spin_lock_irqsave(&m->client->lock, flags); 202 203 if (m->err) { 204 spin_unlock_irqrestore(&m->client->lock, flags); 205 return; 206 } 207 208 m->err = err; 209 210 list_for_each_entry_safe(req, rtmp, &m->req_list, req_list) { 211 list_move(&req->req_list, &cancel_list); 212 } 213 list_for_each_entry_safe(req, rtmp, &m->unsent_req_list, req_list) { 214 list_move(&req->req_list, &cancel_list); 215 } 216 spin_unlock_irqrestore(&m->client->lock, flags); 217 218 list_for_each_entry_safe(req, rtmp, &cancel_list, req_list) { 219 p9_debug(P9_DEBUG_ERROR, "call back req %p\n", req); 220 list_del(&req->req_list); 221 if (!req->t_err) 222 req->t_err = err; 223 p9_client_cb(m->client, req, REQ_STATUS_ERROR); 224 } 225 } 226 227 static int 228 p9_fd_poll(struct p9_client *client, struct poll_table_struct *pt) 229 { 230 int ret, n; 231 struct p9_trans_fd *ts = NULL; 232 233 if (client && client->status == Connected) 234 ts = client->trans; 235 236 if (!ts) 237 return -EREMOTEIO; 238 239 if (!ts->rd->f_op->poll) 240 return -EIO; 241 242 if (!ts->wr->f_op->poll) 243 return -EIO; 244 245 ret = ts->rd->f_op->poll(ts->rd, pt); 246 if (ret < 0) 247 return ret; 248 249 if (ts->rd != ts->wr) { 250 n = ts->wr->f_op->poll(ts->wr, pt); 251 if (n < 0) 252 return n; 253 ret = (ret & ~POLLOUT) | (n & ~POLLIN); 254 } 255 256 return ret; 257 } 258 259 /** 260 * p9_fd_read- read from a fd 261 * @client: client instance 262 * @v: buffer to receive data into 263 * @len: size of receive buffer 264 * 265 */ 266 267 static int p9_fd_read(struct p9_client *client, void *v, int len) 268 { 269 int ret; 270 struct p9_trans_fd *ts = NULL; 271 272 if (client && client->status != Disconnected) 273 ts = client->trans; 274 275 if (!ts) 276 return -EREMOTEIO; 277 278 if (!(ts->rd->f_flags & O_NONBLOCK)) 279 p9_debug(P9_DEBUG_ERROR, "blocking read ...\n"); 280 281 ret = kernel_read(ts->rd, ts->rd->f_pos, v, len); 282 if (ret <= 0 && ret != -ERESTARTSYS && ret != -EAGAIN) 283 client->status = Disconnected; 284 return ret; 285 } 286 287 /** 288 * p9_read_work - called when there is some data to be read from a transport 289 * @work: container of work to be done 290 * 291 */ 292 293 static void p9_read_work(struct work_struct *work) 294 { 295 int n, err; 296 struct p9_conn *m; 297 int status = REQ_STATUS_ERROR; 298 299 m = container_of(work, struct p9_conn, rq); 300 301 if (m->err < 0) 302 return; 303 304 p9_debug(P9_DEBUG_TRANS, "start mux %p pos %zd\n", m, m->rc.offset); 305 306 if (!m->rc.sdata) { 307 m->rc.sdata = m->tmp_buf; 308 m->rc.offset = 0; 309 m->rc.capacity = 7; /* start by reading header */ 310 } 311 312 clear_bit(Rpending, &m->wsched); 313 p9_debug(P9_DEBUG_TRANS, "read mux %p pos %zd size: %zd = %zd\n", 314 m, m->rc.offset, m->rc.capacity, 315 m->rc.capacity - m->rc.offset); 316 err = p9_fd_read(m->client, m->rc.sdata + m->rc.offset, 317 m->rc.capacity - m->rc.offset); 318 p9_debug(P9_DEBUG_TRANS, "mux %p got %d bytes\n", m, err); 319 if (err == -EAGAIN) 320 goto end_clear; 321 322 if (err <= 0) 323 goto error; 324 325 m->rc.offset += err; 326 327 /* header read in */ 328 if ((!m->req) && (m->rc.offset == m->rc.capacity)) { 329 p9_debug(P9_DEBUG_TRANS, "got new header\n"); 330 331 err = p9_parse_header(&m->rc, NULL, NULL, NULL, 0); 332 if (err) { 333 p9_debug(P9_DEBUG_ERROR, 334 "error parsing header: %d\n", err); 335 goto error; 336 } 337 338 if (m->rc.size >= m->client->msize) { 339 p9_debug(P9_DEBUG_ERROR, 340 "requested packet size too big: %d\n", 341 m->rc.size); 342 err = -EIO; 343 goto error; 344 } 345 346 p9_debug(P9_DEBUG_TRANS, 347 "mux %p pkt: size: %d bytes tag: %d\n", 348 m, m->rc.size, m->rc.tag); 349 350 m->req = p9_tag_lookup(m->client, m->rc.tag); 351 if (!m->req || (m->req->status != REQ_STATUS_SENT)) { 352 p9_debug(P9_DEBUG_ERROR, "Unexpected packet tag %d\n", 353 m->rc.tag); 354 err = -EIO; 355 goto error; 356 } 357 358 if (m->req->rc == NULL) { 359 p9_debug(P9_DEBUG_ERROR, 360 "No recv fcall for tag %d (req %p), disconnecting!\n", 361 m->rc.tag, m->req); 362 m->req = NULL; 363 err = -EIO; 364 goto error; 365 } 366 m->rc.sdata = (char *)m->req->rc + sizeof(struct p9_fcall); 367 memcpy(m->rc.sdata, m->tmp_buf, m->rc.capacity); 368 m->rc.capacity = m->rc.size; 369 } 370 371 /* packet is read in 372 * not an else because some packets (like clunk) have no payload 373 */ 374 if ((m->req) && (m->rc.offset == m->rc.capacity)) { 375 p9_debug(P9_DEBUG_TRANS, "got new packet\n"); 376 spin_lock(&m->client->lock); 377 if (m->req->status != REQ_STATUS_ERROR) 378 status = REQ_STATUS_RCVD; 379 list_del(&m->req->req_list); 380 spin_unlock(&m->client->lock); 381 p9_client_cb(m->client, m->req, status); 382 m->rc.sdata = NULL; 383 m->rc.offset = 0; 384 m->rc.capacity = 0; 385 m->req = NULL; 386 } 387 388 end_clear: 389 clear_bit(Rworksched, &m->wsched); 390 391 if (!list_empty(&m->req_list)) { 392 if (test_and_clear_bit(Rpending, &m->wsched)) 393 n = POLLIN; 394 else 395 n = p9_fd_poll(m->client, NULL); 396 397 if ((n & POLLIN) && !test_and_set_bit(Rworksched, &m->wsched)) { 398 p9_debug(P9_DEBUG_TRANS, "sched read work %p\n", m); 399 schedule_work(&m->rq); 400 } 401 } 402 403 return; 404 error: 405 p9_conn_cancel(m, err); 406 clear_bit(Rworksched, &m->wsched); 407 } 408 409 /** 410 * p9_fd_write - write to a socket 411 * @client: client instance 412 * @v: buffer to send data from 413 * @len: size of send buffer 414 * 415 */ 416 417 static int p9_fd_write(struct p9_client *client, void *v, int len) 418 { 419 int ret; 420 mm_segment_t oldfs; 421 struct p9_trans_fd *ts = NULL; 422 423 if (client && client->status != Disconnected) 424 ts = client->trans; 425 426 if (!ts) 427 return -EREMOTEIO; 428 429 if (!(ts->wr->f_flags & O_NONBLOCK)) 430 p9_debug(P9_DEBUG_ERROR, "blocking write ...\n"); 431 432 oldfs = get_fs(); 433 set_fs(get_ds()); 434 /* The cast to a user pointer is valid due to the set_fs() */ 435 ret = vfs_write(ts->wr, (__force void __user *)v, len, &ts->wr->f_pos); 436 set_fs(oldfs); 437 438 if (ret <= 0 && ret != -ERESTARTSYS && ret != -EAGAIN) 439 client->status = Disconnected; 440 return ret; 441 } 442 443 /** 444 * p9_write_work - called when a transport can send some data 445 * @work: container for work to be done 446 * 447 */ 448 449 static void p9_write_work(struct work_struct *work) 450 { 451 int n, err; 452 struct p9_conn *m; 453 struct p9_req_t *req; 454 455 m = container_of(work, struct p9_conn, wq); 456 457 if (m->err < 0) { 458 clear_bit(Wworksched, &m->wsched); 459 return; 460 } 461 462 if (!m->wsize) { 463 spin_lock(&m->client->lock); 464 if (list_empty(&m->unsent_req_list)) { 465 clear_bit(Wworksched, &m->wsched); 466 spin_unlock(&m->client->lock); 467 return; 468 } 469 470 req = list_entry(m->unsent_req_list.next, struct p9_req_t, 471 req_list); 472 req->status = REQ_STATUS_SENT; 473 p9_debug(P9_DEBUG_TRANS, "move req %p\n", req); 474 list_move_tail(&req->req_list, &m->req_list); 475 476 m->wbuf = req->tc->sdata; 477 m->wsize = req->tc->size; 478 m->wpos = 0; 479 spin_unlock(&m->client->lock); 480 } 481 482 p9_debug(P9_DEBUG_TRANS, "mux %p pos %d size %d\n", 483 m, m->wpos, m->wsize); 484 clear_bit(Wpending, &m->wsched); 485 err = p9_fd_write(m->client, m->wbuf + m->wpos, m->wsize - m->wpos); 486 p9_debug(P9_DEBUG_TRANS, "mux %p sent %d bytes\n", m, err); 487 if (err == -EAGAIN) 488 goto end_clear; 489 490 491 if (err < 0) 492 goto error; 493 else if (err == 0) { 494 err = -EREMOTEIO; 495 goto error; 496 } 497 498 m->wpos += err; 499 if (m->wpos == m->wsize) 500 m->wpos = m->wsize = 0; 501 502 end_clear: 503 clear_bit(Wworksched, &m->wsched); 504 505 if (m->wsize || !list_empty(&m->unsent_req_list)) { 506 if (test_and_clear_bit(Wpending, &m->wsched)) 507 n = POLLOUT; 508 else 509 n = p9_fd_poll(m->client, NULL); 510 511 if ((n & POLLOUT) && 512 !test_and_set_bit(Wworksched, &m->wsched)) { 513 p9_debug(P9_DEBUG_TRANS, "sched write work %p\n", m); 514 schedule_work(&m->wq); 515 } 516 } 517 518 return; 519 520 error: 521 p9_conn_cancel(m, err); 522 clear_bit(Wworksched, &m->wsched); 523 } 524 525 static int p9_pollwake(wait_queue_t *wait, unsigned int mode, int sync, void *key) 526 { 527 struct p9_poll_wait *pwait = 528 container_of(wait, struct p9_poll_wait, wait); 529 struct p9_conn *m = pwait->conn; 530 unsigned long flags; 531 532 spin_lock_irqsave(&p9_poll_lock, flags); 533 if (list_empty(&m->poll_pending_link)) 534 list_add_tail(&m->poll_pending_link, &p9_poll_pending_list); 535 spin_unlock_irqrestore(&p9_poll_lock, flags); 536 537 schedule_work(&p9_poll_work); 538 return 1; 539 } 540 541 /** 542 * p9_pollwait - add poll task to the wait queue 543 * @filp: file pointer being polled 544 * @wait_address: wait_q to block on 545 * @p: poll state 546 * 547 * called by files poll operation to add v9fs-poll task to files wait queue 548 */ 549 550 static void 551 p9_pollwait(struct file *filp, wait_queue_head_t *wait_address, poll_table *p) 552 { 553 struct p9_conn *m = container_of(p, struct p9_conn, pt); 554 struct p9_poll_wait *pwait = NULL; 555 int i; 556 557 for (i = 0; i < ARRAY_SIZE(m->poll_wait); i++) { 558 if (m->poll_wait[i].wait_addr == NULL) { 559 pwait = &m->poll_wait[i]; 560 break; 561 } 562 } 563 564 if (!pwait) { 565 p9_debug(P9_DEBUG_ERROR, "not enough wait_address slots\n"); 566 return; 567 } 568 569 pwait->conn = m; 570 pwait->wait_addr = wait_address; 571 init_waitqueue_func_entry(&pwait->wait, p9_pollwake); 572 add_wait_queue(wait_address, &pwait->wait); 573 } 574 575 /** 576 * p9_conn_create - initialize the per-session mux data 577 * @client: client instance 578 * 579 * Note: Creates the polling task if this is the first session. 580 */ 581 582 static void p9_conn_create(struct p9_client *client) 583 { 584 int n; 585 struct p9_trans_fd *ts = client->trans; 586 struct p9_conn *m = &ts->conn; 587 588 p9_debug(P9_DEBUG_TRANS, "client %p msize %d\n", client, client->msize); 589 590 INIT_LIST_HEAD(&m->mux_list); 591 m->client = client; 592 593 INIT_LIST_HEAD(&m->req_list); 594 INIT_LIST_HEAD(&m->unsent_req_list); 595 INIT_WORK(&m->rq, p9_read_work); 596 INIT_WORK(&m->wq, p9_write_work); 597 INIT_LIST_HEAD(&m->poll_pending_link); 598 init_poll_funcptr(&m->pt, p9_pollwait); 599 600 n = p9_fd_poll(client, &m->pt); 601 if (n & POLLIN) { 602 p9_debug(P9_DEBUG_TRANS, "mux %p can read\n", m); 603 set_bit(Rpending, &m->wsched); 604 } 605 606 if (n & POLLOUT) { 607 p9_debug(P9_DEBUG_TRANS, "mux %p can write\n", m); 608 set_bit(Wpending, &m->wsched); 609 } 610 } 611 612 /** 613 * p9_poll_mux - polls a mux and schedules read or write works if necessary 614 * @m: connection to poll 615 * 616 */ 617 618 static void p9_poll_mux(struct p9_conn *m) 619 { 620 int n; 621 622 if (m->err < 0) 623 return; 624 625 n = p9_fd_poll(m->client, NULL); 626 if (n < 0 || n & (POLLERR | POLLHUP | POLLNVAL)) { 627 p9_debug(P9_DEBUG_TRANS, "error mux %p err %d\n", m, n); 628 if (n >= 0) 629 n = -ECONNRESET; 630 p9_conn_cancel(m, n); 631 } 632 633 if (n & POLLIN) { 634 set_bit(Rpending, &m->wsched); 635 p9_debug(P9_DEBUG_TRANS, "mux %p can read\n", m); 636 if (!test_and_set_bit(Rworksched, &m->wsched)) { 637 p9_debug(P9_DEBUG_TRANS, "sched read work %p\n", m); 638 schedule_work(&m->rq); 639 } 640 } 641 642 if (n & POLLOUT) { 643 set_bit(Wpending, &m->wsched); 644 p9_debug(P9_DEBUG_TRANS, "mux %p can write\n", m); 645 if ((m->wsize || !list_empty(&m->unsent_req_list)) && 646 !test_and_set_bit(Wworksched, &m->wsched)) { 647 p9_debug(P9_DEBUG_TRANS, "sched write work %p\n", m); 648 schedule_work(&m->wq); 649 } 650 } 651 } 652 653 /** 654 * p9_fd_request - send 9P request 655 * The function can sleep until the request is scheduled for sending. 656 * The function can be interrupted. Return from the function is not 657 * a guarantee that the request is sent successfully. 658 * 659 * @client: client instance 660 * @req: request to be sent 661 * 662 */ 663 664 static int p9_fd_request(struct p9_client *client, struct p9_req_t *req) 665 { 666 int n; 667 struct p9_trans_fd *ts = client->trans; 668 struct p9_conn *m = &ts->conn; 669 670 p9_debug(P9_DEBUG_TRANS, "mux %p task %p tcall %p id %d\n", 671 m, current, req->tc, req->tc->id); 672 if (m->err < 0) 673 return m->err; 674 675 spin_lock(&client->lock); 676 req->status = REQ_STATUS_UNSENT; 677 list_add_tail(&req->req_list, &m->unsent_req_list); 678 spin_unlock(&client->lock); 679 680 if (test_and_clear_bit(Wpending, &m->wsched)) 681 n = POLLOUT; 682 else 683 n = p9_fd_poll(m->client, NULL); 684 685 if (n & POLLOUT && !test_and_set_bit(Wworksched, &m->wsched)) 686 schedule_work(&m->wq); 687 688 return 0; 689 } 690 691 static int p9_fd_cancel(struct p9_client *client, struct p9_req_t *req) 692 { 693 int ret = 1; 694 695 p9_debug(P9_DEBUG_TRANS, "client %p req %p\n", client, req); 696 697 spin_lock(&client->lock); 698 699 if (req->status == REQ_STATUS_UNSENT) { 700 list_del(&req->req_list); 701 req->status = REQ_STATUS_FLSHD; 702 ret = 0; 703 } 704 spin_unlock(&client->lock); 705 706 return ret; 707 } 708 709 static int p9_fd_cancelled(struct p9_client *client, struct p9_req_t *req) 710 { 711 p9_debug(P9_DEBUG_TRANS, "client %p req %p\n", client, req); 712 713 /* we haven't received a response for oldreq, 714 * remove it from the list. 715 */ 716 spin_lock(&client->lock); 717 list_del(&req->req_list); 718 spin_unlock(&client->lock); 719 720 return 0; 721 } 722 723 /** 724 * parse_opts - parse mount options into p9_fd_opts structure 725 * @params: options string passed from mount 726 * @opts: fd transport-specific structure to parse options into 727 * 728 * Returns 0 upon success, -ERRNO upon failure 729 */ 730 731 static int parse_opts(char *params, struct p9_fd_opts *opts) 732 { 733 char *p; 734 substring_t args[MAX_OPT_ARGS]; 735 int option; 736 char *options, *tmp_options; 737 738 opts->port = P9_PORT; 739 opts->rfd = ~0; 740 opts->wfd = ~0; 741 opts->privport = 0; 742 743 if (!params) 744 return 0; 745 746 tmp_options = kstrdup(params, GFP_KERNEL); 747 if (!tmp_options) { 748 p9_debug(P9_DEBUG_ERROR, 749 "failed to allocate copy of option string\n"); 750 return -ENOMEM; 751 } 752 options = tmp_options; 753 754 while ((p = strsep(&options, ",")) != NULL) { 755 int token; 756 int r; 757 if (!*p) 758 continue; 759 token = match_token(p, tokens, args); 760 if ((token != Opt_err) && (token != Opt_privport)) { 761 r = match_int(&args[0], &option); 762 if (r < 0) { 763 p9_debug(P9_DEBUG_ERROR, 764 "integer field, but no integer?\n"); 765 continue; 766 } 767 } 768 switch (token) { 769 case Opt_port: 770 opts->port = option; 771 break; 772 case Opt_rfdno: 773 opts->rfd = option; 774 break; 775 case Opt_wfdno: 776 opts->wfd = option; 777 break; 778 case Opt_privport: 779 opts->privport = 1; 780 break; 781 default: 782 continue; 783 } 784 } 785 786 kfree(tmp_options); 787 return 0; 788 } 789 790 static int p9_fd_open(struct p9_client *client, int rfd, int wfd) 791 { 792 struct p9_trans_fd *ts = kzalloc(sizeof(struct p9_trans_fd), 793 GFP_KERNEL); 794 if (!ts) 795 return -ENOMEM; 796 797 ts->rd = fget(rfd); 798 ts->wr = fget(wfd); 799 if (!ts->rd || !ts->wr) { 800 if (ts->rd) 801 fput(ts->rd); 802 if (ts->wr) 803 fput(ts->wr); 804 kfree(ts); 805 return -EIO; 806 } 807 808 client->trans = ts; 809 client->status = Connected; 810 811 return 0; 812 } 813 814 static int p9_socket_open(struct p9_client *client, struct socket *csocket) 815 { 816 struct p9_trans_fd *p; 817 struct file *file; 818 819 p = kzalloc(sizeof(struct p9_trans_fd), GFP_KERNEL); 820 if (!p) 821 return -ENOMEM; 822 823 csocket->sk->sk_allocation = GFP_NOIO; 824 file = sock_alloc_file(csocket, 0, NULL); 825 if (IS_ERR(file)) { 826 pr_err("%s (%d): failed to map fd\n", 827 __func__, task_pid_nr(current)); 828 sock_release(csocket); 829 kfree(p); 830 return PTR_ERR(file); 831 } 832 833 get_file(file); 834 p->wr = p->rd = file; 835 client->trans = p; 836 client->status = Connected; 837 838 p->rd->f_flags |= O_NONBLOCK; 839 840 p9_conn_create(client); 841 return 0; 842 } 843 844 /** 845 * p9_mux_destroy - cancels all pending requests of mux 846 * @m: mux to destroy 847 * 848 */ 849 850 static void p9_conn_destroy(struct p9_conn *m) 851 { 852 p9_debug(P9_DEBUG_TRANS, "mux %p prev %p next %p\n", 853 m, m->mux_list.prev, m->mux_list.next); 854 855 p9_mux_poll_stop(m); 856 cancel_work_sync(&m->rq); 857 cancel_work_sync(&m->wq); 858 859 p9_conn_cancel(m, -ECONNRESET); 860 861 m->client = NULL; 862 } 863 864 /** 865 * p9_fd_close - shutdown file descriptor transport 866 * @client: client instance 867 * 868 */ 869 870 static void p9_fd_close(struct p9_client *client) 871 { 872 struct p9_trans_fd *ts; 873 874 if (!client) 875 return; 876 877 ts = client->trans; 878 if (!ts) 879 return; 880 881 client->status = Disconnected; 882 883 p9_conn_destroy(&ts->conn); 884 885 if (ts->rd) 886 fput(ts->rd); 887 if (ts->wr) 888 fput(ts->wr); 889 890 kfree(ts); 891 } 892 893 /* 894 * stolen from NFS - maybe should be made a generic function? 895 */ 896 static inline int valid_ipaddr4(const char *buf) 897 { 898 int rc, count, in[4]; 899 900 rc = sscanf(buf, "%d.%d.%d.%d", &in[0], &in[1], &in[2], &in[3]); 901 if (rc != 4) 902 return -EINVAL; 903 for (count = 0; count < 4; count++) { 904 if (in[count] > 255) 905 return -EINVAL; 906 } 907 return 0; 908 } 909 910 static int p9_bind_privport(struct socket *sock) 911 { 912 struct sockaddr_in cl; 913 int port, err = -EINVAL; 914 915 memset(&cl, 0, sizeof(cl)); 916 cl.sin_family = AF_INET; 917 cl.sin_addr.s_addr = INADDR_ANY; 918 for (port = p9_ipport_resv_max; port >= p9_ipport_resv_min; port--) { 919 cl.sin_port = htons((ushort)port); 920 err = kernel_bind(sock, (struct sockaddr *)&cl, sizeof(cl)); 921 if (err != -EADDRINUSE) 922 break; 923 } 924 return err; 925 } 926 927 928 static int 929 p9_fd_create_tcp(struct p9_client *client, const char *addr, char *args) 930 { 931 int err; 932 struct socket *csocket; 933 struct sockaddr_in sin_server; 934 struct p9_fd_opts opts; 935 936 err = parse_opts(args, &opts); 937 if (err < 0) 938 return err; 939 940 if (valid_ipaddr4(addr) < 0) 941 return -EINVAL; 942 943 csocket = NULL; 944 945 sin_server.sin_family = AF_INET; 946 sin_server.sin_addr.s_addr = in_aton(addr); 947 sin_server.sin_port = htons(opts.port); 948 err = __sock_create(current->nsproxy->net_ns, PF_INET, 949 SOCK_STREAM, IPPROTO_TCP, &csocket, 1); 950 if (err) { 951 pr_err("%s (%d): problem creating socket\n", 952 __func__, task_pid_nr(current)); 953 return err; 954 } 955 956 if (opts.privport) { 957 err = p9_bind_privport(csocket); 958 if (err < 0) { 959 pr_err("%s (%d): problem binding to privport\n", 960 __func__, task_pid_nr(current)); 961 sock_release(csocket); 962 return err; 963 } 964 } 965 966 err = csocket->ops->connect(csocket, 967 (struct sockaddr *)&sin_server, 968 sizeof(struct sockaddr_in), 0); 969 if (err < 0) { 970 pr_err("%s (%d): problem connecting socket to %s\n", 971 __func__, task_pid_nr(current), addr); 972 sock_release(csocket); 973 return err; 974 } 975 976 return p9_socket_open(client, csocket); 977 } 978 979 static int 980 p9_fd_create_unix(struct p9_client *client, const char *addr, char *args) 981 { 982 int err; 983 struct socket *csocket; 984 struct sockaddr_un sun_server; 985 986 csocket = NULL; 987 988 if (strlen(addr) >= UNIX_PATH_MAX) { 989 pr_err("%s (%d): address too long: %s\n", 990 __func__, task_pid_nr(current), addr); 991 return -ENAMETOOLONG; 992 } 993 994 sun_server.sun_family = PF_UNIX; 995 strcpy(sun_server.sun_path, addr); 996 err = __sock_create(current->nsproxy->net_ns, PF_UNIX, 997 SOCK_STREAM, 0, &csocket, 1); 998 if (err < 0) { 999 pr_err("%s (%d): problem creating socket\n", 1000 __func__, task_pid_nr(current)); 1001 1002 return err; 1003 } 1004 err = csocket->ops->connect(csocket, (struct sockaddr *)&sun_server, 1005 sizeof(struct sockaddr_un) - 1, 0); 1006 if (err < 0) { 1007 pr_err("%s (%d): problem connecting socket: %s: %d\n", 1008 __func__, task_pid_nr(current), addr, err); 1009 sock_release(csocket); 1010 return err; 1011 } 1012 1013 return p9_socket_open(client, csocket); 1014 } 1015 1016 static int 1017 p9_fd_create(struct p9_client *client, const char *addr, char *args) 1018 { 1019 int err; 1020 struct p9_fd_opts opts; 1021 1022 parse_opts(args, &opts); 1023 1024 if (opts.rfd == ~0 || opts.wfd == ~0) { 1025 pr_err("Insufficient options for proto=fd\n"); 1026 return -ENOPROTOOPT; 1027 } 1028 1029 err = p9_fd_open(client, opts.rfd, opts.wfd); 1030 if (err < 0) 1031 return err; 1032 1033 p9_conn_create(client); 1034 1035 return 0; 1036 } 1037 1038 static struct p9_trans_module p9_tcp_trans = { 1039 .name = "tcp", 1040 .maxsize = MAX_SOCK_BUF, 1041 .def = 0, 1042 .create = p9_fd_create_tcp, 1043 .close = p9_fd_close, 1044 .request = p9_fd_request, 1045 .cancel = p9_fd_cancel, 1046 .cancelled = p9_fd_cancelled, 1047 .owner = THIS_MODULE, 1048 }; 1049 1050 static struct p9_trans_module p9_unix_trans = { 1051 .name = "unix", 1052 .maxsize = MAX_SOCK_BUF, 1053 .def = 0, 1054 .create = p9_fd_create_unix, 1055 .close = p9_fd_close, 1056 .request = p9_fd_request, 1057 .cancel = p9_fd_cancel, 1058 .cancelled = p9_fd_cancelled, 1059 .owner = THIS_MODULE, 1060 }; 1061 1062 static struct p9_trans_module p9_fd_trans = { 1063 .name = "fd", 1064 .maxsize = MAX_SOCK_BUF, 1065 .def = 0, 1066 .create = p9_fd_create, 1067 .close = p9_fd_close, 1068 .request = p9_fd_request, 1069 .cancel = p9_fd_cancel, 1070 .cancelled = p9_fd_cancelled, 1071 .owner = THIS_MODULE, 1072 }; 1073 1074 /** 1075 * p9_poll_proc - poll worker thread 1076 * @a: thread state and arguments 1077 * 1078 * polls all v9fs transports for new events and queues the appropriate 1079 * work to the work queue 1080 * 1081 */ 1082 1083 static void p9_poll_workfn(struct work_struct *work) 1084 { 1085 unsigned long flags; 1086 1087 p9_debug(P9_DEBUG_TRANS, "start %p\n", current); 1088 1089 spin_lock_irqsave(&p9_poll_lock, flags); 1090 while (!list_empty(&p9_poll_pending_list)) { 1091 struct p9_conn *conn = list_first_entry(&p9_poll_pending_list, 1092 struct p9_conn, 1093 poll_pending_link); 1094 list_del_init(&conn->poll_pending_link); 1095 spin_unlock_irqrestore(&p9_poll_lock, flags); 1096 1097 p9_poll_mux(conn); 1098 1099 spin_lock_irqsave(&p9_poll_lock, flags); 1100 } 1101 spin_unlock_irqrestore(&p9_poll_lock, flags); 1102 1103 p9_debug(P9_DEBUG_TRANS, "finish\n"); 1104 } 1105 1106 int p9_trans_fd_init(void) 1107 { 1108 v9fs_register_trans(&p9_tcp_trans); 1109 v9fs_register_trans(&p9_unix_trans); 1110 v9fs_register_trans(&p9_fd_trans); 1111 1112 return 0; 1113 } 1114 1115 void p9_trans_fd_exit(void) 1116 { 1117 flush_work(&p9_poll_work); 1118 v9fs_unregister_trans(&p9_tcp_trans); 1119 v9fs_unregister_trans(&p9_unix_trans); 1120 v9fs_unregister_trans(&p9_fd_trans); 1121 } 1122