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 }; 67 68 /** 69 * struct p9_trans_fd - transport state 70 * @rd: reference to file to read from 71 * @wr: reference of file to write to 72 * @conn: connection state reference 73 * 74 */ 75 76 struct p9_trans_fd { 77 struct file *rd; 78 struct file *wr; 79 struct p9_conn *conn; 80 }; 81 82 /* 83 * Option Parsing (code inspired by NFS code) 84 * - a little lazy - parse all fd-transport options 85 */ 86 87 enum { 88 /* Options that take integer arguments */ 89 Opt_port, Opt_rfdno, Opt_wfdno, Opt_err, 90 }; 91 92 static const match_table_t tokens = { 93 {Opt_port, "port=%u"}, 94 {Opt_rfdno, "rfdno=%u"}, 95 {Opt_wfdno, "wfdno=%u"}, 96 {Opt_err, NULL}, 97 }; 98 99 enum { 100 Rworksched = 1, /* read work scheduled or running */ 101 Rpending = 2, /* can read */ 102 Wworksched = 4, /* write work scheduled or running */ 103 Wpending = 8, /* can write */ 104 }; 105 106 struct p9_poll_wait { 107 struct p9_conn *conn; 108 wait_queue_t wait; 109 wait_queue_head_t *wait_addr; 110 }; 111 112 /** 113 * struct p9_conn - fd mux connection state information 114 * @mux_list: list link for mux to manage multiple connections (?) 115 * @client: reference to client instance for this connection 116 * @err: error state 117 * @req_list: accounting for requests which have been sent 118 * @unsent_req_list: accounting for requests that haven't been sent 119 * @req: current request being processed (if any) 120 * @tmp_buf: temporary buffer to read in header 121 * @rsize: amount to read for current frame 122 * @rpos: read position in current frame 123 * @rbuf: current read buffer 124 * @wpos: write position for current frame 125 * @wsize: amount of data to write for current frame 126 * @wbuf: current write buffer 127 * @poll_pending_link: pending links to be polled per conn 128 * @poll_wait: array of wait_q's for various worker threads 129 * @pt: poll state 130 * @rq: current read work 131 * @wq: current write work 132 * @wsched: ???? 133 * 134 */ 135 136 struct p9_conn { 137 struct list_head mux_list; 138 struct p9_client *client; 139 int err; 140 struct list_head req_list; 141 struct list_head unsent_req_list; 142 struct p9_req_t *req; 143 char tmp_buf[7]; 144 int rsize; 145 int rpos; 146 char *rbuf; 147 int wpos; 148 int wsize; 149 char *wbuf; 150 struct list_head poll_pending_link; 151 struct p9_poll_wait poll_wait[MAXPOLLWADDR]; 152 poll_table pt; 153 struct work_struct rq; 154 struct work_struct wq; 155 unsigned long wsched; 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 void p9_mux_poll_stop(struct p9_conn *m) 165 { 166 unsigned long flags; 167 int i; 168 169 for (i = 0; i < ARRAY_SIZE(m->poll_wait); i++) { 170 struct p9_poll_wait *pwait = &m->poll_wait[i]; 171 172 if (pwait->wait_addr) { 173 remove_wait_queue(pwait->wait_addr, &pwait->wait); 174 pwait->wait_addr = NULL; 175 } 176 } 177 178 spin_lock_irqsave(&p9_poll_lock, flags); 179 list_del_init(&m->poll_pending_link); 180 spin_unlock_irqrestore(&p9_poll_lock, flags); 181 } 182 183 /** 184 * p9_conn_cancel - cancel all pending requests with error 185 * @m: mux data 186 * @err: error code 187 * 188 */ 189 190 static void p9_conn_cancel(struct p9_conn *m, int err) 191 { 192 struct p9_req_t *req, *rtmp; 193 unsigned long flags; 194 LIST_HEAD(cancel_list); 195 196 p9_debug(P9_DEBUG_ERROR, "mux %p err %d\n", m, err); 197 198 spin_lock_irqsave(&m->client->lock, flags); 199 200 if (m->err) { 201 spin_unlock_irqrestore(&m->client->lock, flags); 202 return; 203 } 204 205 m->err = err; 206 207 list_for_each_entry_safe(req, rtmp, &m->req_list, req_list) { 208 req->status = REQ_STATUS_ERROR; 209 if (!req->t_err) 210 req->t_err = err; 211 list_move(&req->req_list, &cancel_list); 212 } 213 list_for_each_entry_safe(req, rtmp, &m->unsent_req_list, req_list) { 214 req->status = REQ_STATUS_ERROR; 215 if (!req->t_err) 216 req->t_err = err; 217 list_move(&req->req_list, &cancel_list); 218 } 219 spin_unlock_irqrestore(&m->client->lock, flags); 220 221 list_for_each_entry_safe(req, rtmp, &cancel_list, req_list) { 222 p9_debug(P9_DEBUG_ERROR, "call back req %p\n", req); 223 list_del(&req->req_list); 224 p9_client_cb(m->client, req); 225 } 226 } 227 228 static int 229 p9_fd_poll(struct p9_client *client, struct poll_table_struct *pt) 230 { 231 int ret, n; 232 struct p9_trans_fd *ts = NULL; 233 234 if (client && client->status == Connected) 235 ts = client->trans; 236 237 if (!ts) 238 return -EREMOTEIO; 239 240 if (!ts->rd->f_op || !ts->rd->f_op->poll) 241 return -EIO; 242 243 if (!ts->wr->f_op || !ts->wr->f_op->poll) 244 return -EIO; 245 246 ret = ts->rd->f_op->poll(ts->rd, pt); 247 if (ret < 0) 248 return ret; 249 250 if (ts->rd != ts->wr) { 251 n = ts->wr->f_op->poll(ts->wr, pt); 252 if (n < 0) 253 return n; 254 ret = (ret & ~POLLOUT) | (n & ~POLLIN); 255 } 256 257 return ret; 258 } 259 260 /** 261 * p9_fd_read- read from a fd 262 * @client: client instance 263 * @v: buffer to receive data into 264 * @len: size of receive buffer 265 * 266 */ 267 268 static int p9_fd_read(struct p9_client *client, void *v, int len) 269 { 270 int ret; 271 struct p9_trans_fd *ts = NULL; 272 273 if (client && client->status != Disconnected) 274 ts = client->trans; 275 276 if (!ts) 277 return -EREMOTEIO; 278 279 if (!(ts->rd->f_flags & O_NONBLOCK)) 280 p9_debug(P9_DEBUG_ERROR, "blocking read ...\n"); 281 282 ret = kernel_read(ts->rd, ts->rd->f_pos, v, len); 283 if (ret <= 0 && ret != -ERESTARTSYS && ret != -EAGAIN) 284 client->status = Disconnected; 285 return ret; 286 } 287 288 /** 289 * p9_read_work - called when there is some data to be read from a transport 290 * @work: container of work to be done 291 * 292 */ 293 294 static void p9_read_work(struct work_struct *work) 295 { 296 int n, err; 297 struct p9_conn *m; 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 %d\n", m, m->rpos); 305 306 if (!m->rbuf) { 307 m->rbuf = m->tmp_buf; 308 m->rpos = 0; 309 m->rsize = 7; /* start by reading header */ 310 } 311 312 clear_bit(Rpending, &m->wsched); 313 p9_debug(P9_DEBUG_TRANS, "read mux %p pos %d size: %d = %d\n", 314 m, m->rpos, m->rsize, m->rsize-m->rpos); 315 err = p9_fd_read(m->client, m->rbuf + m->rpos, 316 m->rsize - m->rpos); 317 p9_debug(P9_DEBUG_TRANS, "mux %p got %d bytes\n", m, err); 318 if (err == -EAGAIN) { 319 goto end_clear; 320 } 321 322 if (err <= 0) 323 goto error; 324 325 m->rpos += err; 326 327 if ((!m->req) && (m->rpos == m->rsize)) { /* header read in */ 328 u16 tag; 329 p9_debug(P9_DEBUG_TRANS, "got new header\n"); 330 331 n = le32_to_cpu(*(__le32 *) m->rbuf); /* read packet size */ 332 if (n >= m->client->msize) { 333 p9_debug(P9_DEBUG_ERROR, 334 "requested packet size too big: %d\n", n); 335 err = -EIO; 336 goto error; 337 } 338 339 tag = le16_to_cpu(*(__le16 *) (m->rbuf+5)); /* read tag */ 340 p9_debug(P9_DEBUG_TRANS, 341 "mux %p pkt: size: %d bytes tag: %d\n", m, n, tag); 342 343 m->req = p9_tag_lookup(m->client, tag); 344 if (!m->req || (m->req->status != REQ_STATUS_SENT && 345 m->req->status != REQ_STATUS_FLSH)) { 346 p9_debug(P9_DEBUG_ERROR, "Unexpected packet tag %d\n", 347 tag); 348 err = -EIO; 349 goto error; 350 } 351 352 if (m->req->rc == NULL) { 353 m->req->rc = kmalloc(sizeof(struct p9_fcall) + 354 m->client->msize, GFP_NOFS); 355 if (!m->req->rc) { 356 m->req = NULL; 357 err = -ENOMEM; 358 goto error; 359 } 360 } 361 m->rbuf = (char *)m->req->rc + sizeof(struct p9_fcall); 362 memcpy(m->rbuf, m->tmp_buf, m->rsize); 363 m->rsize = n; 364 } 365 366 /* not an else because some packets (like clunk) have no payload */ 367 if ((m->req) && (m->rpos == m->rsize)) { /* packet is read in */ 368 p9_debug(P9_DEBUG_TRANS, "got new packet\n"); 369 spin_lock(&m->client->lock); 370 if (m->req->status != REQ_STATUS_ERROR) 371 m->req->status = REQ_STATUS_RCVD; 372 list_del(&m->req->req_list); 373 spin_unlock(&m->client->lock); 374 p9_client_cb(m->client, m->req); 375 m->rbuf = NULL; 376 m->rpos = 0; 377 m->rsize = 0; 378 m->req = NULL; 379 } 380 381 end_clear: 382 clear_bit(Rworksched, &m->wsched); 383 384 if (!list_empty(&m->req_list)) { 385 if (test_and_clear_bit(Rpending, &m->wsched)) 386 n = POLLIN; 387 else 388 n = p9_fd_poll(m->client, NULL); 389 390 if ((n & POLLIN) && !test_and_set_bit(Rworksched, &m->wsched)) { 391 p9_debug(P9_DEBUG_TRANS, "sched read work %p\n", m); 392 schedule_work(&m->rq); 393 } 394 } 395 396 return; 397 error: 398 p9_conn_cancel(m, err); 399 clear_bit(Rworksched, &m->wsched); 400 } 401 402 /** 403 * p9_fd_write - write to a socket 404 * @client: client instance 405 * @v: buffer to send data from 406 * @len: size of send buffer 407 * 408 */ 409 410 static int p9_fd_write(struct p9_client *client, void *v, int len) 411 { 412 int ret; 413 mm_segment_t oldfs; 414 struct p9_trans_fd *ts = NULL; 415 416 if (client && client->status != Disconnected) 417 ts = client->trans; 418 419 if (!ts) 420 return -EREMOTEIO; 421 422 if (!(ts->wr->f_flags & O_NONBLOCK)) 423 p9_debug(P9_DEBUG_ERROR, "blocking write ...\n"); 424 425 oldfs = get_fs(); 426 set_fs(get_ds()); 427 /* The cast to a user pointer is valid due to the set_fs() */ 428 ret = vfs_write(ts->wr, (__force void __user *)v, len, &ts->wr->f_pos); 429 set_fs(oldfs); 430 431 if (ret <= 0 && ret != -ERESTARTSYS && ret != -EAGAIN) 432 client->status = Disconnected; 433 return ret; 434 } 435 436 /** 437 * p9_write_work - called when a transport can send some data 438 * @work: container for work to be done 439 * 440 */ 441 442 static void p9_write_work(struct work_struct *work) 443 { 444 int n, err; 445 struct p9_conn *m; 446 struct p9_req_t *req; 447 448 m = container_of(work, struct p9_conn, wq); 449 450 if (m->err < 0) { 451 clear_bit(Wworksched, &m->wsched); 452 return; 453 } 454 455 if (!m->wsize) { 456 spin_lock(&m->client->lock); 457 if (list_empty(&m->unsent_req_list)) { 458 clear_bit(Wworksched, &m->wsched); 459 spin_unlock(&m->client->lock); 460 return; 461 } 462 463 req = list_entry(m->unsent_req_list.next, struct p9_req_t, 464 req_list); 465 req->status = REQ_STATUS_SENT; 466 p9_debug(P9_DEBUG_TRANS, "move req %p\n", req); 467 list_move_tail(&req->req_list, &m->req_list); 468 469 m->wbuf = req->tc->sdata; 470 m->wsize = req->tc->size; 471 m->wpos = 0; 472 spin_unlock(&m->client->lock); 473 } 474 475 p9_debug(P9_DEBUG_TRANS, "mux %p pos %d size %d\n", 476 m, m->wpos, m->wsize); 477 clear_bit(Wpending, &m->wsched); 478 err = p9_fd_write(m->client, m->wbuf + m->wpos, m->wsize - m->wpos); 479 p9_debug(P9_DEBUG_TRANS, "mux %p sent %d bytes\n", m, err); 480 if (err == -EAGAIN) 481 goto end_clear; 482 483 484 if (err < 0) 485 goto error; 486 else if (err == 0) { 487 err = -EREMOTEIO; 488 goto error; 489 } 490 491 m->wpos += err; 492 if (m->wpos == m->wsize) 493 m->wpos = m->wsize = 0; 494 495 end_clear: 496 clear_bit(Wworksched, &m->wsched); 497 498 if (m->wsize || !list_empty(&m->unsent_req_list)) { 499 if (test_and_clear_bit(Wpending, &m->wsched)) 500 n = POLLOUT; 501 else 502 n = p9_fd_poll(m->client, NULL); 503 504 if ((n & POLLOUT) && 505 !test_and_set_bit(Wworksched, &m->wsched)) { 506 p9_debug(P9_DEBUG_TRANS, "sched write work %p\n", m); 507 schedule_work(&m->wq); 508 } 509 } 510 511 return; 512 513 error: 514 p9_conn_cancel(m, err); 515 clear_bit(Wworksched, &m->wsched); 516 } 517 518 static int p9_pollwake(wait_queue_t *wait, unsigned int mode, int sync, void *key) 519 { 520 struct p9_poll_wait *pwait = 521 container_of(wait, struct p9_poll_wait, wait); 522 struct p9_conn *m = pwait->conn; 523 unsigned long flags; 524 525 spin_lock_irqsave(&p9_poll_lock, flags); 526 if (list_empty(&m->poll_pending_link)) 527 list_add_tail(&m->poll_pending_link, &p9_poll_pending_list); 528 spin_unlock_irqrestore(&p9_poll_lock, flags); 529 530 schedule_work(&p9_poll_work); 531 return 1; 532 } 533 534 /** 535 * p9_pollwait - add poll task to the wait queue 536 * @filp: file pointer being polled 537 * @wait_address: wait_q to block on 538 * @p: poll state 539 * 540 * called by files poll operation to add v9fs-poll task to files wait queue 541 */ 542 543 static void 544 p9_pollwait(struct file *filp, wait_queue_head_t *wait_address, poll_table *p) 545 { 546 struct p9_conn *m = container_of(p, struct p9_conn, pt); 547 struct p9_poll_wait *pwait = NULL; 548 int i; 549 550 for (i = 0; i < ARRAY_SIZE(m->poll_wait); i++) { 551 if (m->poll_wait[i].wait_addr == NULL) { 552 pwait = &m->poll_wait[i]; 553 break; 554 } 555 } 556 557 if (!pwait) { 558 p9_debug(P9_DEBUG_ERROR, "not enough wait_address slots\n"); 559 return; 560 } 561 562 pwait->conn = m; 563 pwait->wait_addr = wait_address; 564 init_waitqueue_func_entry(&pwait->wait, p9_pollwake); 565 add_wait_queue(wait_address, &pwait->wait); 566 } 567 568 /** 569 * p9_conn_create - allocate and initialize the per-session mux data 570 * @client: client instance 571 * 572 * Note: Creates the polling task if this is the first session. 573 */ 574 575 static struct p9_conn *p9_conn_create(struct p9_client *client) 576 { 577 int n; 578 struct p9_conn *m; 579 580 p9_debug(P9_DEBUG_TRANS, "client %p msize %d\n", client, client->msize); 581 m = kzalloc(sizeof(struct p9_conn), GFP_KERNEL); 582 if (!m) 583 return ERR_PTR(-ENOMEM); 584 585 INIT_LIST_HEAD(&m->mux_list); 586 m->client = client; 587 588 INIT_LIST_HEAD(&m->req_list); 589 INIT_LIST_HEAD(&m->unsent_req_list); 590 INIT_WORK(&m->rq, p9_read_work); 591 INIT_WORK(&m->wq, p9_write_work); 592 INIT_LIST_HEAD(&m->poll_pending_link); 593 init_poll_funcptr(&m->pt, p9_pollwait); 594 595 n = p9_fd_poll(client, &m->pt); 596 if (n & POLLIN) { 597 p9_debug(P9_DEBUG_TRANS, "mux %p can read\n", m); 598 set_bit(Rpending, &m->wsched); 599 } 600 601 if (n & POLLOUT) { 602 p9_debug(P9_DEBUG_TRANS, "mux %p can write\n", m); 603 set_bit(Wpending, &m->wsched); 604 } 605 606 return m; 607 } 608 609 /** 610 * p9_poll_mux - polls a mux and schedules read or write works if necessary 611 * @m: connection to poll 612 * 613 */ 614 615 static void p9_poll_mux(struct p9_conn *m) 616 { 617 int n; 618 619 if (m->err < 0) 620 return; 621 622 n = p9_fd_poll(m->client, NULL); 623 if (n < 0 || n & (POLLERR | POLLHUP | POLLNVAL)) { 624 p9_debug(P9_DEBUG_TRANS, "error mux %p err %d\n", m, n); 625 if (n >= 0) 626 n = -ECONNRESET; 627 p9_conn_cancel(m, n); 628 } 629 630 if (n & POLLIN) { 631 set_bit(Rpending, &m->wsched); 632 p9_debug(P9_DEBUG_TRANS, "mux %p can read\n", m); 633 if (!test_and_set_bit(Rworksched, &m->wsched)) { 634 p9_debug(P9_DEBUG_TRANS, "sched read work %p\n", m); 635 schedule_work(&m->rq); 636 } 637 } 638 639 if (n & POLLOUT) { 640 set_bit(Wpending, &m->wsched); 641 p9_debug(P9_DEBUG_TRANS, "mux %p can write\n", m); 642 if ((m->wsize || !list_empty(&m->unsent_req_list)) && 643 !test_and_set_bit(Wworksched, &m->wsched)) { 644 p9_debug(P9_DEBUG_TRANS, "sched write work %p\n", m); 645 schedule_work(&m->wq); 646 } 647 } 648 } 649 650 /** 651 * p9_fd_request - send 9P request 652 * The function can sleep until the request is scheduled for sending. 653 * The function can be interrupted. Return from the function is not 654 * a guarantee that the request is sent successfully. 655 * 656 * @client: client instance 657 * @req: request to be sent 658 * 659 */ 660 661 static int p9_fd_request(struct p9_client *client, struct p9_req_t *req) 662 { 663 int n; 664 struct p9_trans_fd *ts = client->trans; 665 struct p9_conn *m = ts->conn; 666 667 p9_debug(P9_DEBUG_TRANS, "mux %p task %p tcall %p id %d\n", 668 m, current, req->tc, req->tc->id); 669 if (m->err < 0) 670 return m->err; 671 672 spin_lock(&client->lock); 673 req->status = REQ_STATUS_UNSENT; 674 list_add_tail(&req->req_list, &m->unsent_req_list); 675 spin_unlock(&client->lock); 676 677 if (test_and_clear_bit(Wpending, &m->wsched)) 678 n = POLLOUT; 679 else 680 n = p9_fd_poll(m->client, NULL); 681 682 if (n & POLLOUT && !test_and_set_bit(Wworksched, &m->wsched)) 683 schedule_work(&m->wq); 684 685 return 0; 686 } 687 688 static int p9_fd_cancel(struct p9_client *client, struct p9_req_t *req) 689 { 690 int ret = 1; 691 692 p9_debug(P9_DEBUG_TRANS, "client %p req %p\n", client, req); 693 694 spin_lock(&client->lock); 695 696 if (req->status == REQ_STATUS_UNSENT) { 697 list_del(&req->req_list); 698 req->status = REQ_STATUS_FLSHD; 699 ret = 0; 700 } else if (req->status == REQ_STATUS_SENT) 701 req->status = REQ_STATUS_FLSH; 702 703 spin_unlock(&client->lock); 704 705 return ret; 706 } 707 708 /** 709 * parse_opts - parse mount options into p9_fd_opts structure 710 * @params: options string passed from mount 711 * @opts: fd transport-specific structure to parse options into 712 * 713 * Returns 0 upon success, -ERRNO upon failure 714 */ 715 716 static int parse_opts(char *params, struct p9_fd_opts *opts) 717 { 718 char *p; 719 substring_t args[MAX_OPT_ARGS]; 720 int option; 721 char *options, *tmp_options; 722 723 opts->port = P9_PORT; 724 opts->rfd = ~0; 725 opts->wfd = ~0; 726 727 if (!params) 728 return 0; 729 730 tmp_options = kstrdup(params, GFP_KERNEL); 731 if (!tmp_options) { 732 p9_debug(P9_DEBUG_ERROR, 733 "failed to allocate copy of option string\n"); 734 return -ENOMEM; 735 } 736 options = tmp_options; 737 738 while ((p = strsep(&options, ",")) != NULL) { 739 int token; 740 int r; 741 if (!*p) 742 continue; 743 token = match_token(p, tokens, args); 744 if (token != Opt_err) { 745 r = match_int(&args[0], &option); 746 if (r < 0) { 747 p9_debug(P9_DEBUG_ERROR, 748 "integer field, but no integer?\n"); 749 continue; 750 } 751 } 752 switch (token) { 753 case Opt_port: 754 opts->port = option; 755 break; 756 case Opt_rfdno: 757 opts->rfd = option; 758 break; 759 case Opt_wfdno: 760 opts->wfd = option; 761 break; 762 default: 763 continue; 764 } 765 } 766 767 kfree(tmp_options); 768 return 0; 769 } 770 771 static int p9_fd_open(struct p9_client *client, int rfd, int wfd) 772 { 773 struct p9_trans_fd *ts = kmalloc(sizeof(struct p9_trans_fd), 774 GFP_KERNEL); 775 if (!ts) 776 return -ENOMEM; 777 778 ts->rd = fget(rfd); 779 ts->wr = fget(wfd); 780 if (!ts->rd || !ts->wr) { 781 if (ts->rd) 782 fput(ts->rd); 783 if (ts->wr) 784 fput(ts->wr); 785 kfree(ts); 786 return -EIO; 787 } 788 789 client->trans = ts; 790 client->status = Connected; 791 792 return 0; 793 } 794 795 static int p9_socket_open(struct p9_client *client, struct socket *csocket) 796 { 797 struct p9_trans_fd *p; 798 struct file *file; 799 int ret; 800 801 p = kmalloc(sizeof(struct p9_trans_fd), GFP_KERNEL); 802 if (!p) 803 return -ENOMEM; 804 805 csocket->sk->sk_allocation = GFP_NOIO; 806 file = sock_alloc_file(csocket, 0, NULL); 807 if (IS_ERR(file)) { 808 pr_err("%s (%d): failed to map fd\n", 809 __func__, task_pid_nr(current)); 810 sock_release(csocket); 811 kfree(p); 812 return PTR_ERR(file); 813 } 814 815 get_file(file); 816 p->wr = p->rd = file; 817 client->trans = p; 818 client->status = Connected; 819 820 p->rd->f_flags |= O_NONBLOCK; 821 822 p->conn = p9_conn_create(client); 823 if (IS_ERR(p->conn)) { 824 ret = PTR_ERR(p->conn); 825 p->conn = NULL; 826 kfree(p); 827 sockfd_put(csocket); 828 sockfd_put(csocket); 829 return ret; 830 } 831 return 0; 832 } 833 834 /** 835 * p9_mux_destroy - cancels all pending requests and frees mux resources 836 * @m: mux to destroy 837 * 838 */ 839 840 static void p9_conn_destroy(struct p9_conn *m) 841 { 842 p9_debug(P9_DEBUG_TRANS, "mux %p prev %p next %p\n", 843 m, m->mux_list.prev, m->mux_list.next); 844 845 p9_mux_poll_stop(m); 846 cancel_work_sync(&m->rq); 847 cancel_work_sync(&m->wq); 848 849 p9_conn_cancel(m, -ECONNRESET); 850 851 m->client = NULL; 852 kfree(m); 853 } 854 855 /** 856 * p9_fd_close - shutdown file descriptor transport 857 * @client: client instance 858 * 859 */ 860 861 static void p9_fd_close(struct p9_client *client) 862 { 863 struct p9_trans_fd *ts; 864 865 if (!client) 866 return; 867 868 ts = client->trans; 869 if (!ts) 870 return; 871 872 client->status = Disconnected; 873 874 p9_conn_destroy(ts->conn); 875 876 if (ts->rd) 877 fput(ts->rd); 878 if (ts->wr) 879 fput(ts->wr); 880 881 kfree(ts); 882 } 883 884 /* 885 * stolen from NFS - maybe should be made a generic function? 886 */ 887 static inline int valid_ipaddr4(const char *buf) 888 { 889 int rc, count, in[4]; 890 891 rc = sscanf(buf, "%d.%d.%d.%d", &in[0], &in[1], &in[2], &in[3]); 892 if (rc != 4) 893 return -EINVAL; 894 for (count = 0; count < 4; count++) { 895 if (in[count] > 255) 896 return -EINVAL; 897 } 898 return 0; 899 } 900 901 static int 902 p9_fd_create_tcp(struct p9_client *client, const char *addr, char *args) 903 { 904 int err; 905 struct socket *csocket; 906 struct sockaddr_in sin_server; 907 struct p9_fd_opts opts; 908 909 err = parse_opts(args, &opts); 910 if (err < 0) 911 return err; 912 913 if (valid_ipaddr4(addr) < 0) 914 return -EINVAL; 915 916 csocket = NULL; 917 918 sin_server.sin_family = AF_INET; 919 sin_server.sin_addr.s_addr = in_aton(addr); 920 sin_server.sin_port = htons(opts.port); 921 err = __sock_create(read_pnet(¤t->nsproxy->net_ns), PF_INET, 922 SOCK_STREAM, IPPROTO_TCP, &csocket, 1); 923 if (err) { 924 pr_err("%s (%d): problem creating socket\n", 925 __func__, task_pid_nr(current)); 926 return err; 927 } 928 929 err = csocket->ops->connect(csocket, 930 (struct sockaddr *)&sin_server, 931 sizeof(struct sockaddr_in), 0); 932 if (err < 0) { 933 pr_err("%s (%d): problem connecting socket to %s\n", 934 __func__, task_pid_nr(current), addr); 935 sock_release(csocket); 936 return err; 937 } 938 939 return p9_socket_open(client, csocket); 940 } 941 942 static int 943 p9_fd_create_unix(struct p9_client *client, const char *addr, char *args) 944 { 945 int err; 946 struct socket *csocket; 947 struct sockaddr_un sun_server; 948 949 csocket = NULL; 950 951 if (strlen(addr) >= UNIX_PATH_MAX) { 952 pr_err("%s (%d): address too long: %s\n", 953 __func__, task_pid_nr(current), addr); 954 return -ENAMETOOLONG; 955 } 956 957 sun_server.sun_family = PF_UNIX; 958 strcpy(sun_server.sun_path, addr); 959 err = __sock_create(read_pnet(¤t->nsproxy->net_ns), PF_UNIX, 960 SOCK_STREAM, 0, &csocket, 1); 961 if (err < 0) { 962 pr_err("%s (%d): problem creating socket\n", 963 __func__, task_pid_nr(current)); 964 965 return err; 966 } 967 err = csocket->ops->connect(csocket, (struct sockaddr *)&sun_server, 968 sizeof(struct sockaddr_un) - 1, 0); 969 if (err < 0) { 970 pr_err("%s (%d): problem connecting socket: %s: %d\n", 971 __func__, task_pid_nr(current), addr, err); 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(struct p9_client *client, const char *addr, char *args) 981 { 982 int err; 983 struct p9_fd_opts opts; 984 struct p9_trans_fd *p; 985 986 parse_opts(args, &opts); 987 988 if (opts.rfd == ~0 || opts.wfd == ~0) { 989 pr_err("Insufficient options for proto=fd\n"); 990 return -ENOPROTOOPT; 991 } 992 993 err = p9_fd_open(client, opts.rfd, opts.wfd); 994 if (err < 0) 995 return err; 996 997 p = (struct p9_trans_fd *) client->trans; 998 p->conn = p9_conn_create(client); 999 if (IS_ERR(p->conn)) { 1000 err = PTR_ERR(p->conn); 1001 p->conn = NULL; 1002 fput(p->rd); 1003 fput(p->wr); 1004 return err; 1005 } 1006 1007 return 0; 1008 } 1009 1010 static struct p9_trans_module p9_tcp_trans = { 1011 .name = "tcp", 1012 .maxsize = MAX_SOCK_BUF, 1013 .def = 1, 1014 .create = p9_fd_create_tcp, 1015 .close = p9_fd_close, 1016 .request = p9_fd_request, 1017 .cancel = p9_fd_cancel, 1018 .owner = THIS_MODULE, 1019 }; 1020 1021 static struct p9_trans_module p9_unix_trans = { 1022 .name = "unix", 1023 .maxsize = MAX_SOCK_BUF, 1024 .def = 0, 1025 .create = p9_fd_create_unix, 1026 .close = p9_fd_close, 1027 .request = p9_fd_request, 1028 .cancel = p9_fd_cancel, 1029 .owner = THIS_MODULE, 1030 }; 1031 1032 static struct p9_trans_module p9_fd_trans = { 1033 .name = "fd", 1034 .maxsize = MAX_SOCK_BUF, 1035 .def = 0, 1036 .create = p9_fd_create, 1037 .close = p9_fd_close, 1038 .request = p9_fd_request, 1039 .cancel = p9_fd_cancel, 1040 .owner = THIS_MODULE, 1041 }; 1042 1043 /** 1044 * p9_poll_proc - poll worker thread 1045 * @a: thread state and arguments 1046 * 1047 * polls all v9fs transports for new events and queues the appropriate 1048 * work to the work queue 1049 * 1050 */ 1051 1052 static void p9_poll_workfn(struct work_struct *work) 1053 { 1054 unsigned long flags; 1055 1056 p9_debug(P9_DEBUG_TRANS, "start %p\n", current); 1057 1058 spin_lock_irqsave(&p9_poll_lock, flags); 1059 while (!list_empty(&p9_poll_pending_list)) { 1060 struct p9_conn *conn = list_first_entry(&p9_poll_pending_list, 1061 struct p9_conn, 1062 poll_pending_link); 1063 list_del_init(&conn->poll_pending_link); 1064 spin_unlock_irqrestore(&p9_poll_lock, flags); 1065 1066 p9_poll_mux(conn); 1067 1068 spin_lock_irqsave(&p9_poll_lock, flags); 1069 } 1070 spin_unlock_irqrestore(&p9_poll_lock, flags); 1071 1072 p9_debug(P9_DEBUG_TRANS, "finish\n"); 1073 } 1074 1075 int p9_trans_fd_init(void) 1076 { 1077 v9fs_register_trans(&p9_tcp_trans); 1078 v9fs_register_trans(&p9_unix_trans); 1079 v9fs_register_trans(&p9_fd_trans); 1080 1081 return 0; 1082 } 1083 1084 void p9_trans_fd_exit(void) 1085 { 1086 flush_work(&p9_poll_work); 1087 v9fs_unregister_trans(&p9_tcp_trans); 1088 v9fs_unregister_trans(&p9_unix_trans); 1089 v9fs_unregister_trans(&p9_fd_trans); 1090 } 1091