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 62struct 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 74enum { 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 81static 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 89enum { 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 96struct 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 * @rsize: amount to read for current frame 112 * @rpos: read position in current frame 113 * @rbuf: current read buffer 114 * @wpos: write position for current frame 115 * @wsize: amount of data to write for current frame 116 * @wbuf: current write buffer 117 * @poll_pending_link: pending links to be polled per conn 118 * @poll_wait: array of wait_q's for various worker threads 119 * @pt: poll state 120 * @rq: current read work 121 * @wq: current write work 122 * @wsched: ???? 123 * 124 */ 125 126struct p9_conn { 127 struct list_head mux_list; 128 struct p9_client *client; 129 int err; 130 struct list_head req_list; 131 struct list_head unsent_req_list; 132 struct p9_req_t *req; 133 char tmp_buf[7]; 134 int rsize; 135 int rpos; 136 char *rbuf; 137 int wpos; 138 int wsize; 139 char *wbuf; 140 struct list_head poll_pending_link; 141 struct p9_poll_wait poll_wait[MAXPOLLWADDR]; 142 poll_table pt; 143 struct work_struct rq; 144 struct work_struct wq; 145 unsigned long wsched; 146}; 147 148/** 149 * struct p9_trans_fd - transport state 150 * @rd: reference to file to read from 151 * @wr: reference of file to write to 152 * @conn: connection state reference 153 * 154 */ 155 156struct p9_trans_fd { 157 struct file *rd; 158 struct file *wr; 159 struct p9_conn conn; 160}; 161 162static void p9_poll_workfn(struct work_struct *work); 163 164static DEFINE_SPINLOCK(p9_poll_lock); 165static LIST_HEAD(p9_poll_pending_list); 166static DECLARE_WORK(p9_poll_work, p9_poll_workfn); 167 168static unsigned int p9_ipport_resv_min = P9_DEF_MIN_RESVPORT; 169static unsigned int p9_ipport_resv_max = P9_DEF_MAX_RESVPORT; 170 171static void p9_mux_poll_stop(struct p9_conn *m) 172{ 173 unsigned long flags; 174 int i; 175 176 for (i = 0; i < ARRAY_SIZE(m->poll_wait); i++) { 177 struct p9_poll_wait *pwait = &m->poll_wait[i]; 178 179 if (pwait->wait_addr) { 180 remove_wait_queue(pwait->wait_addr, &pwait->wait); 181 pwait->wait_addr = NULL; 182 } 183 } 184 185 spin_lock_irqsave(&p9_poll_lock, flags); 186 list_del_init(&m->poll_pending_link); 187 spin_unlock_irqrestore(&p9_poll_lock, flags); 188} 189 190/** 191 * p9_conn_cancel - cancel all pending requests with error 192 * @m: mux data 193 * @err: error code 194 * 195 */ 196 197static void p9_conn_cancel(struct p9_conn *m, int err) 198{ 199 struct p9_req_t *req, *rtmp; 200 unsigned long flags; 201 LIST_HEAD(cancel_list); 202 203 p9_debug(P9_DEBUG_ERROR, "mux %p err %d\n", m, err); 204 205 spin_lock_irqsave(&m->client->lock, flags); 206 207 if (m->err) { 208 spin_unlock_irqrestore(&m->client->lock, flags); 209 return; 210 } 211 212 m->err = err; 213 214 list_for_each_entry_safe(req, rtmp, &m->req_list, req_list) { 215 list_move(&req->req_list, &cancel_list); 216 } 217 list_for_each_entry_safe(req, rtmp, &m->unsent_req_list, req_list) { 218 list_move(&req->req_list, &cancel_list); 219 } 220 spin_unlock_irqrestore(&m->client->lock, flags); 221 222 list_for_each_entry_safe(req, rtmp, &cancel_list, req_list) { 223 p9_debug(P9_DEBUG_ERROR, "call back req %p\n", req); 224 list_del(&req->req_list); 225 if (!req->t_err) 226 req->t_err = err; 227 p9_client_cb(m->client, req, REQ_STATUS_ERROR); 228 } 229} 230 231static int 232p9_fd_poll(struct p9_client *client, struct poll_table_struct *pt) 233{ 234 int ret, n; 235 struct p9_trans_fd *ts = NULL; 236 237 if (client && client->status == Connected) 238 ts = client->trans; 239 240 if (!ts) 241 return -EREMOTEIO; 242 243 if (!ts->rd->f_op->poll) 244 return -EIO; 245 246 if (!ts->wr->f_op->poll) 247 return -EIO; 248 249 ret = ts->rd->f_op->poll(ts->rd, pt); 250 if (ret < 0) 251 return ret; 252 253 if (ts->rd != ts->wr) { 254 n = ts->wr->f_op->poll(ts->wr, pt); 255 if (n < 0) 256 return n; 257 ret = (ret & ~POLLOUT) | (n & ~POLLIN); 258 } 259 260 return ret; 261} 262 263/** 264 * p9_fd_read- read from a fd 265 * @client: client instance 266 * @v: buffer to receive data into 267 * @len: size of receive buffer 268 * 269 */ 270 271static int p9_fd_read(struct p9_client *client, void *v, int len) 272{ 273 int ret; 274 struct p9_trans_fd *ts = NULL; 275 276 if (client && client->status != Disconnected) 277 ts = client->trans; 278 279 if (!ts) 280 return -EREMOTEIO; 281 282 if (!(ts->rd->f_flags & O_NONBLOCK)) 283 p9_debug(P9_DEBUG_ERROR, "blocking read ...\n"); 284 285 ret = kernel_read(ts->rd, ts->rd->f_pos, v, len); 286 if (ret <= 0 && ret != -ERESTARTSYS && ret != -EAGAIN) 287 client->status = Disconnected; 288 return ret; 289} 290 291/** 292 * p9_read_work - called when there is some data to be read from a transport 293 * @work: container of work to be done 294 * 295 */ 296 297static void p9_read_work(struct work_struct *work) 298{ 299 int n, err; 300 struct p9_conn *m; 301 int status = REQ_STATUS_ERROR; 302 303 m = container_of(work, struct p9_conn, rq); 304 305 if (m->err < 0) 306 return; 307 308 p9_debug(P9_DEBUG_TRANS, "start mux %p pos %d\n", m, m->rpos); 309 310 if (!m->rbuf) { 311 m->rbuf = m->tmp_buf; 312 m->rpos = 0; 313 m->rsize = 7; /* start by reading header */ 314 } 315 316 clear_bit(Rpending, &m->wsched); 317 p9_debug(P9_DEBUG_TRANS, "read mux %p pos %d size: %d = %d\n", 318 m, m->rpos, m->rsize, m->rsize-m->rpos); 319 err = p9_fd_read(m->client, m->rbuf + m->rpos, 320 m->rsize - m->rpos); 321 p9_debug(P9_DEBUG_TRANS, "mux %p got %d bytes\n", m, err); 322 if (err == -EAGAIN) { 323 goto end_clear; 324 } 325 326 if (err <= 0) 327 goto error; 328 329 m->rpos += err; 330 331 if ((!m->req) && (m->rpos == m->rsize)) { /* header read in */ 332 u16 tag; 333 p9_debug(P9_DEBUG_TRANS, "got new header\n"); 334 335 n = le32_to_cpu(*(__le32 *) m->rbuf); /* read packet size */ 336 if (n >= m->client->msize) { 337 p9_debug(P9_DEBUG_ERROR, 338 "requested packet size too big: %d\n", n); 339 err = -EIO; 340 goto error; 341 } 342 343 tag = le16_to_cpu(*(__le16 *) (m->rbuf+5)); /* read tag */ 344 p9_debug(P9_DEBUG_TRANS, 345 "mux %p pkt: size: %d bytes tag: %d\n", m, n, tag); 346 347 m->req = p9_tag_lookup(m->client, tag); 348 if (!m->req || (m->req->status != REQ_STATUS_SENT)) { 349 p9_debug(P9_DEBUG_ERROR, "Unexpected packet tag %d\n", 350 tag); 351 err = -EIO; 352 goto error; 353 } 354 355 if (m->req->rc == NULL) { 356 m->req->rc = kmalloc(sizeof(struct p9_fcall) + 357 m->client->msize, GFP_NOFS); 358 if (!m->req->rc) { 359 m->req = NULL; 360 err = -ENOMEM; 361 goto error; 362 } 363 } 364 m->rbuf = (char *)m->req->rc + sizeof(struct p9_fcall); 365 memcpy(m->rbuf, m->tmp_buf, m->rsize); 366 m->rsize = n; 367 } 368 369 /* not an else because some packets (like clunk) have no payload */ 370 if ((m->req) && (m->rpos == m->rsize)) { /* packet is read in */ 371 p9_debug(P9_DEBUG_TRANS, "got new packet\n"); 372 spin_lock(&m->client->lock); 373 if (m->req->status != REQ_STATUS_ERROR) 374 status = REQ_STATUS_RCVD; 375 list_del(&m->req->req_list); 376 spin_unlock(&m->client->lock); 377 p9_client_cb(m->client, m->req, status); 378 m->rbuf = NULL; 379 m->rpos = 0; 380 m->rsize = 0; 381 m->req = NULL; 382 } 383 384end_clear: 385 clear_bit(Rworksched, &m->wsched); 386 387 if (!list_empty(&m->req_list)) { 388 if (test_and_clear_bit(Rpending, &m->wsched)) 389 n = POLLIN; 390 else 391 n = p9_fd_poll(m->client, NULL); 392 393 if ((n & POLLIN) && !test_and_set_bit(Rworksched, &m->wsched)) { 394 p9_debug(P9_DEBUG_TRANS, "sched read work %p\n", m); 395 schedule_work(&m->rq); 396 } 397 } 398 399 return; 400error: 401 p9_conn_cancel(m, err); 402 clear_bit(Rworksched, &m->wsched); 403} 404 405/** 406 * p9_fd_write - write to a socket 407 * @client: client instance 408 * @v: buffer to send data from 409 * @len: size of send buffer 410 * 411 */ 412 413static int p9_fd_write(struct p9_client *client, void *v, int len) 414{ 415 int ret; 416 mm_segment_t oldfs; 417 struct p9_trans_fd *ts = NULL; 418 419 if (client && client->status != Disconnected) 420 ts = client->trans; 421 422 if (!ts) 423 return -EREMOTEIO; 424 425 if (!(ts->wr->f_flags & O_NONBLOCK)) 426 p9_debug(P9_DEBUG_ERROR, "blocking write ...\n"); 427 428 oldfs = get_fs(); 429 set_fs(get_ds()); 430 /* The cast to a user pointer is valid due to the set_fs() */ 431 ret = vfs_write(ts->wr, (__force void __user *)v, len, &ts->wr->f_pos); 432 set_fs(oldfs); 433 434 if (ret <= 0 && ret != -ERESTARTSYS && ret != -EAGAIN) 435 client->status = Disconnected; 436 return ret; 437} 438 439/** 440 * p9_write_work - called when a transport can send some data 441 * @work: container for work to be done 442 * 443 */ 444 445static void p9_write_work(struct work_struct *work) 446{ 447 int n, err; 448 struct p9_conn *m; 449 struct p9_req_t *req; 450 451 m = container_of(work, struct p9_conn, wq); 452 453 if (m->err < 0) { 454 clear_bit(Wworksched, &m->wsched); 455 return; 456 } 457 458 if (!m->wsize) { 459 spin_lock(&m->client->lock); 460 if (list_empty(&m->unsent_req_list)) { 461 clear_bit(Wworksched, &m->wsched); 462 spin_unlock(&m->client->lock); 463 return; 464 } 465 466 req = list_entry(m->unsent_req_list.next, struct p9_req_t, 467 req_list); 468 req->status = REQ_STATUS_SENT; 469 p9_debug(P9_DEBUG_TRANS, "move req %p\n", req); 470 list_move_tail(&req->req_list, &m->req_list); 471 472 m->wbuf = req->tc->sdata; 473 m->wsize = req->tc->size; 474 m->wpos = 0; 475 spin_unlock(&m->client->lock); 476 } 477 478 p9_debug(P9_DEBUG_TRANS, "mux %p pos %d size %d\n", 479 m, m->wpos, m->wsize); 480 clear_bit(Wpending, &m->wsched); 481 err = p9_fd_write(m->client, m->wbuf + m->wpos, m->wsize - m->wpos); 482 p9_debug(P9_DEBUG_TRANS, "mux %p sent %d bytes\n", m, err); 483 if (err == -EAGAIN) 484 goto end_clear; 485 486 487 if (err < 0) 488 goto error; 489 else if (err == 0) { 490 err = -EREMOTEIO; 491 goto error; 492 } 493 494 m->wpos += err; 495 if (m->wpos == m->wsize) 496 m->wpos = m->wsize = 0; 497 498end_clear: 499 clear_bit(Wworksched, &m->wsched); 500 501 if (m->wsize || !list_empty(&m->unsent_req_list)) { 502 if (test_and_clear_bit(Wpending, &m->wsched)) 503 n = POLLOUT; 504 else 505 n = p9_fd_poll(m->client, NULL); 506 507 if ((n & POLLOUT) && 508 !test_and_set_bit(Wworksched, &m->wsched)) { 509 p9_debug(P9_DEBUG_TRANS, "sched write work %p\n", m); 510 schedule_work(&m->wq); 511 } 512 } 513 514 return; 515 516error: 517 p9_conn_cancel(m, err); 518 clear_bit(Wworksched, &m->wsched); 519} 520 521static int p9_pollwake(wait_queue_t *wait, unsigned int mode, int sync, void *key) 522{ 523 struct p9_poll_wait *pwait = 524 container_of(wait, struct p9_poll_wait, wait); 525 struct p9_conn *m = pwait->conn; 526 unsigned long flags; 527 528 spin_lock_irqsave(&p9_poll_lock, flags); 529 if (list_empty(&m->poll_pending_link)) 530 list_add_tail(&m->poll_pending_link, &p9_poll_pending_list); 531 spin_unlock_irqrestore(&p9_poll_lock, flags); 532 533 schedule_work(&p9_poll_work); 534 return 1; 535} 536 537/** 538 * p9_pollwait - add poll task to the wait queue 539 * @filp: file pointer being polled 540 * @wait_address: wait_q to block on 541 * @p: poll state 542 * 543 * called by files poll operation to add v9fs-poll task to files wait queue 544 */ 545 546static void 547p9_pollwait(struct file *filp, wait_queue_head_t *wait_address, poll_table *p) 548{ 549 struct p9_conn *m = container_of(p, struct p9_conn, pt); 550 struct p9_poll_wait *pwait = NULL; 551 int i; 552 553 for (i = 0; i < ARRAY_SIZE(m->poll_wait); i++) { 554 if (m->poll_wait[i].wait_addr == NULL) { 555 pwait = &m->poll_wait[i]; 556 break; 557 } 558 } 559 560 if (!pwait) { 561 p9_debug(P9_DEBUG_ERROR, "not enough wait_address slots\n"); 562 return; 563 } 564 565 pwait->conn = m; 566 pwait->wait_addr = wait_address; 567 init_waitqueue_func_entry(&pwait->wait, p9_pollwake); 568 add_wait_queue(wait_address, &pwait->wait); 569} 570 571/** 572 * p9_conn_create - initialize the per-session mux data 573 * @client: client instance 574 * 575 * Note: Creates the polling task if this is the first session. 576 */ 577 578static void p9_conn_create(struct p9_client *client) 579{ 580 int n; 581 struct p9_trans_fd *ts = client->trans; 582 struct p9_conn *m = &ts->conn; 583 584 p9_debug(P9_DEBUG_TRANS, "client %p msize %d\n", client, client->msize); 585 586 INIT_LIST_HEAD(&m->mux_list); 587 m->client = client; 588 589 INIT_LIST_HEAD(&m->req_list); 590 INIT_LIST_HEAD(&m->unsent_req_list); 591 INIT_WORK(&m->rq, p9_read_work); 592 INIT_WORK(&m->wq, p9_write_work); 593 INIT_LIST_HEAD(&m->poll_pending_link); 594 init_poll_funcptr(&m->pt, p9_pollwait); 595 596 n = p9_fd_poll(client, &m->pt); 597 if (n & POLLIN) { 598 p9_debug(P9_DEBUG_TRANS, "mux %p can read\n", m); 599 set_bit(Rpending, &m->wsched); 600 } 601 602 if (n & POLLOUT) { 603 p9_debug(P9_DEBUG_TRANS, "mux %p can write\n", m); 604 set_bit(Wpending, &m->wsched); 605 } 606} 607 608/** 609 * p9_poll_mux - polls a mux and schedules read or write works if necessary 610 * @m: connection to poll 611 * 612 */ 613 614static void p9_poll_mux(struct p9_conn *m) 615{ 616 int n; 617 618 if (m->err < 0) 619 return; 620 621 n = p9_fd_poll(m->client, NULL); 622 if (n < 0 || n & (POLLERR | POLLHUP | POLLNVAL)) { 623 p9_debug(P9_DEBUG_TRANS, "error mux %p err %d\n", m, n); 624 if (n >= 0) 625 n = -ECONNRESET; 626 p9_conn_cancel(m, n); 627 } 628 629 if (n & POLLIN) { 630 set_bit(Rpending, &m->wsched); 631 p9_debug(P9_DEBUG_TRANS, "mux %p can read\n", m); 632 if (!test_and_set_bit(Rworksched, &m->wsched)) { 633 p9_debug(P9_DEBUG_TRANS, "sched read work %p\n", m); 634 schedule_work(&m->rq); 635 } 636 } 637 638 if (n & POLLOUT) { 639 set_bit(Wpending, &m->wsched); 640 p9_debug(P9_DEBUG_TRANS, "mux %p can write\n", m); 641 if ((m->wsize || !list_empty(&m->unsent_req_list)) && 642 !test_and_set_bit(Wworksched, &m->wsched)) { 643 p9_debug(P9_DEBUG_TRANS, "sched write work %p\n", m); 644 schedule_work(&m->wq); 645 } 646 } 647} 648 649/** 650 * p9_fd_request - send 9P request 651 * The function can sleep until the request is scheduled for sending. 652 * The function can be interrupted. Return from the function is not 653 * a guarantee that the request is sent successfully. 654 * 655 * @client: client instance 656 * @req: request to be sent 657 * 658 */ 659 660static int p9_fd_request(struct p9_client *client, struct p9_req_t *req) 661{ 662 int n; 663 struct p9_trans_fd *ts = client->trans; 664 struct p9_conn *m = &ts->conn; 665 666 p9_debug(P9_DEBUG_TRANS, "mux %p task %p tcall %p id %d\n", 667 m, current, req->tc, req->tc->id); 668 if (m->err < 0) 669 return m->err; 670 671 spin_lock(&client->lock); 672 req->status = REQ_STATUS_UNSENT; 673 list_add_tail(&req->req_list, &m->unsent_req_list); 674 spin_unlock(&client->lock); 675 676 if (test_and_clear_bit(Wpending, &m->wsched)) 677 n = POLLOUT; 678 else 679 n = p9_fd_poll(m->client, NULL); 680 681 if (n & POLLOUT && !test_and_set_bit(Wworksched, &m->wsched)) 682 schedule_work(&m->wq); 683 684 return 0; 685} 686 687static int p9_fd_cancel(struct p9_client *client, struct p9_req_t *req) 688{ 689 int ret = 1; 690 691 p9_debug(P9_DEBUG_TRANS, "client %p req %p\n", client, req); 692 693 spin_lock(&client->lock); 694 695 if (req->status == REQ_STATUS_UNSENT) { 696 list_del(&req->req_list); 697 req->status = REQ_STATUS_FLSHD; 698 ret = 0; 699 } 700 spin_unlock(&client->lock); 701 702 return ret; 703} 704 705static int p9_fd_cancelled(struct p9_client *client, struct p9_req_t *req) 706{ 707 p9_debug(P9_DEBUG_TRANS, "client %p req %p\n", client, req); 708 709 /* we haven't received a response for oldreq, 710 * remove it from the list. 711 */ 712 spin_lock(&client->lock); 713 list_del(&req->req_list); 714 spin_unlock(&client->lock); 715 716 return 0; 717} 718 719/** 720 * parse_opts - parse mount options into p9_fd_opts structure 721 * @params: options string passed from mount 722 * @opts: fd transport-specific structure to parse options into 723 * 724 * Returns 0 upon success, -ERRNO upon failure 725 */ 726 727static int parse_opts(char *params, struct p9_fd_opts *opts) 728{ 729 char *p; 730 substring_t args[MAX_OPT_ARGS]; 731 int option; 732 char *options, *tmp_options; 733 734 opts->port = P9_PORT; 735 opts->rfd = ~0; 736 opts->wfd = ~0; 737 738 if (!params) 739 return 0; 740 741 tmp_options = kstrdup(params, GFP_KERNEL); 742 if (!tmp_options) { 743 p9_debug(P9_DEBUG_ERROR, 744 "failed to allocate copy of option string\n"); 745 return -ENOMEM; 746 } 747 options = tmp_options; 748 749 while ((p = strsep(&options, ",")) != NULL) { 750 int token; 751 int r; 752 if (!*p) 753 continue; 754 token = match_token(p, tokens, args); 755 if ((token != Opt_err) && (token != Opt_privport)) { 756 r = match_int(&args[0], &option); 757 if (r < 0) { 758 p9_debug(P9_DEBUG_ERROR, 759 "integer field, but no integer?\n"); 760 continue; 761 } 762 } 763 switch (token) { 764 case Opt_port: 765 opts->port = option; 766 break; 767 case Opt_rfdno: 768 opts->rfd = option; 769 break; 770 case Opt_wfdno: 771 opts->wfd = option; 772 break; 773 case Opt_privport: 774 opts->privport = 1; 775 break; 776 default: 777 continue; 778 } 779 } 780 781 kfree(tmp_options); 782 return 0; 783} 784 785static int p9_fd_open(struct p9_client *client, int rfd, int wfd) 786{ 787 struct p9_trans_fd *ts = kzalloc(sizeof(struct p9_trans_fd), 788 GFP_KERNEL); 789 if (!ts) 790 return -ENOMEM; 791 792 ts->rd = fget(rfd); 793 ts->wr = fget(wfd); 794 if (!ts->rd || !ts->wr) { 795 if (ts->rd) 796 fput(ts->rd); 797 if (ts->wr) 798 fput(ts->wr); 799 kfree(ts); 800 return -EIO; 801 } 802 803 client->trans = ts; 804 client->status = Connected; 805 806 return 0; 807} 808 809static int p9_socket_open(struct p9_client *client, struct socket *csocket) 810{ 811 struct p9_trans_fd *p; 812 struct file *file; 813 814 p = kzalloc(sizeof(struct p9_trans_fd), GFP_KERNEL); 815 if (!p) 816 return -ENOMEM; 817 818 csocket->sk->sk_allocation = GFP_NOIO; 819 file = sock_alloc_file(csocket, 0, NULL); 820 if (IS_ERR(file)) { 821 pr_err("%s (%d): failed to map fd\n", 822 __func__, task_pid_nr(current)); 823 sock_release(csocket); 824 kfree(p); 825 return PTR_ERR(file); 826 } 827 828 get_file(file); 829 p->wr = p->rd = file; 830 client->trans = p; 831 client->status = Connected; 832 833 p->rd->f_flags |= O_NONBLOCK; 834 835 p9_conn_create(client); 836 return 0; 837} 838 839/** 840 * p9_mux_destroy - cancels all pending requests of mux 841 * @m: mux to destroy 842 * 843 */ 844 845static void p9_conn_destroy(struct p9_conn *m) 846{ 847 p9_debug(P9_DEBUG_TRANS, "mux %p prev %p next %p\n", 848 m, m->mux_list.prev, m->mux_list.next); 849 850 p9_mux_poll_stop(m); 851 cancel_work_sync(&m->rq); 852 cancel_work_sync(&m->wq); 853 854 p9_conn_cancel(m, -ECONNRESET); 855 856 m->client = NULL; 857} 858 859/** 860 * p9_fd_close - shutdown file descriptor transport 861 * @client: client instance 862 * 863 */ 864 865static void p9_fd_close(struct p9_client *client) 866{ 867 struct p9_trans_fd *ts; 868 869 if (!client) 870 return; 871 872 ts = client->trans; 873 if (!ts) 874 return; 875 876 client->status = Disconnected; 877 878 p9_conn_destroy(&ts->conn); 879 880 if (ts->rd) 881 fput(ts->rd); 882 if (ts->wr) 883 fput(ts->wr); 884 885 kfree(ts); 886} 887 888/* 889 * stolen from NFS - maybe should be made a generic function? 890 */ 891static inline int valid_ipaddr4(const char *buf) 892{ 893 int rc, count, in[4]; 894 895 rc = sscanf(buf, "%d.%d.%d.%d", &in[0], &in[1], &in[2], &in[3]); 896 if (rc != 4) 897 return -EINVAL; 898 for (count = 0; count < 4; count++) { 899 if (in[count] > 255) 900 return -EINVAL; 901 } 902 return 0; 903} 904 905static int p9_bind_privport(struct socket *sock) 906{ 907 struct sockaddr_in cl; 908 int port, err = -EINVAL; 909 910 memset(&cl, 0, sizeof(cl)); 911 cl.sin_family = AF_INET; 912 cl.sin_addr.s_addr = INADDR_ANY; 913 for (port = p9_ipport_resv_max; port >= p9_ipport_resv_min; port--) { 914 cl.sin_port = htons((ushort)port); 915 err = kernel_bind(sock, (struct sockaddr *)&cl, sizeof(cl)); 916 if (err != -EADDRINUSE) 917 break; 918 } 919 return err; 920} 921 922 923static int 924p9_fd_create_tcp(struct p9_client *client, const char *addr, char *args) 925{ 926 int err; 927 struct socket *csocket; 928 struct sockaddr_in sin_server; 929 struct p9_fd_opts opts; 930 931 err = parse_opts(args, &opts); 932 if (err < 0) 933 return err; 934 935 if (valid_ipaddr4(addr) < 0) 936 return -EINVAL; 937 938 csocket = NULL; 939 940 sin_server.sin_family = AF_INET; 941 sin_server.sin_addr.s_addr = in_aton(addr); 942 sin_server.sin_port = htons(opts.port); 943 err = __sock_create(read_pnet(¤t->nsproxy->net_ns), PF_INET, 944 SOCK_STREAM, IPPROTO_TCP, &csocket, 1); 945 if (err) { 946 pr_err("%s (%d): problem creating socket\n", 947 __func__, task_pid_nr(current)); 948 return err; 949 } 950 951 if (opts.privport) { 952 err = p9_bind_privport(csocket); 953 if (err < 0) { 954 pr_err("%s (%d): problem binding to privport\n", 955 __func__, task_pid_nr(current)); 956 sock_release(csocket); 957 return err; 958 } 959 } 960 961 err = csocket->ops->connect(csocket, 962 (struct sockaddr *)&sin_server, 963 sizeof(struct sockaddr_in), 0); 964 if (err < 0) { 965 pr_err("%s (%d): problem connecting socket to %s\n", 966 __func__, task_pid_nr(current), addr); 967 sock_release(csocket); 968 return err; 969 } 970 971 return p9_socket_open(client, csocket); 972} 973 974static int 975p9_fd_create_unix(struct p9_client *client, const char *addr, char *args) 976{ 977 int err; 978 struct socket *csocket; 979 struct sockaddr_un sun_server; 980 981 csocket = NULL; 982 983 if (strlen(addr) >= UNIX_PATH_MAX) { 984 pr_err("%s (%d): address too long: %s\n", 985 __func__, task_pid_nr(current), addr); 986 return -ENAMETOOLONG; 987 } 988 989 sun_server.sun_family = PF_UNIX; 990 strcpy(sun_server.sun_path, addr); 991 err = __sock_create(read_pnet(¤t->nsproxy->net_ns), PF_UNIX, 992 SOCK_STREAM, 0, &csocket, 1); 993 if (err < 0) { 994 pr_err("%s (%d): problem creating socket\n", 995 __func__, task_pid_nr(current)); 996 997 return err; 998 } 999 err = csocket->ops->connect(csocket, (struct sockaddr *)&sun_server, 1000 sizeof(struct sockaddr_un) - 1, 0); 1001 if (err < 0) { 1002 pr_err("%s (%d): problem connecting socket: %s: %d\n", 1003 __func__, task_pid_nr(current), addr, err); 1004 sock_release(csocket); 1005 return err; 1006 } 1007 1008 return p9_socket_open(client, csocket); 1009} 1010 1011static int 1012p9_fd_create(struct p9_client *client, const char *addr, char *args) 1013{ 1014 int err; 1015 struct p9_fd_opts opts; 1016 struct p9_trans_fd *p; 1017 1018 parse_opts(args, &opts); 1019 1020 if (opts.rfd == ~0 || opts.wfd == ~0) { 1021 pr_err("Insufficient options for proto=fd\n"); 1022 return -ENOPROTOOPT; 1023 } 1024 1025 err = p9_fd_open(client, opts.rfd, opts.wfd); 1026 if (err < 0) 1027 return err; 1028 1029 p = (struct p9_trans_fd *) client->trans; 1030 p9_conn_create(client); 1031 1032 return 0; 1033} 1034 1035static struct p9_trans_module p9_tcp_trans = { 1036 .name = "tcp", 1037 .maxsize = MAX_SOCK_BUF, 1038 .def = 0, 1039 .create = p9_fd_create_tcp, 1040 .close = p9_fd_close, 1041 .request = p9_fd_request, 1042 .cancel = p9_fd_cancel, 1043 .cancelled = p9_fd_cancelled, 1044 .owner = THIS_MODULE, 1045}; 1046 1047static struct p9_trans_module p9_unix_trans = { 1048 .name = "unix", 1049 .maxsize = MAX_SOCK_BUF, 1050 .def = 0, 1051 .create = p9_fd_create_unix, 1052 .close = p9_fd_close, 1053 .request = p9_fd_request, 1054 .cancel = p9_fd_cancel, 1055 .cancelled = p9_fd_cancelled, 1056 .owner = THIS_MODULE, 1057}; 1058 1059static struct p9_trans_module p9_fd_trans = { 1060 .name = "fd", 1061 .maxsize = MAX_SOCK_BUF, 1062 .def = 0, 1063 .create = p9_fd_create, 1064 .close = p9_fd_close, 1065 .request = p9_fd_request, 1066 .cancel = p9_fd_cancel, 1067 .cancelled = p9_fd_cancelled, 1068 .owner = THIS_MODULE, 1069}; 1070 1071/** 1072 * p9_poll_proc - poll worker thread 1073 * @a: thread state and arguments 1074 * 1075 * polls all v9fs transports for new events and queues the appropriate 1076 * work to the work queue 1077 * 1078 */ 1079 1080static void p9_poll_workfn(struct work_struct *work) 1081{ 1082 unsigned long flags; 1083 1084 p9_debug(P9_DEBUG_TRANS, "start %p\n", current); 1085 1086 spin_lock_irqsave(&p9_poll_lock, flags); 1087 while (!list_empty(&p9_poll_pending_list)) { 1088 struct p9_conn *conn = list_first_entry(&p9_poll_pending_list, 1089 struct p9_conn, 1090 poll_pending_link); 1091 list_del_init(&conn->poll_pending_link); 1092 spin_unlock_irqrestore(&p9_poll_lock, flags); 1093 1094 p9_poll_mux(conn); 1095 1096 spin_lock_irqsave(&p9_poll_lock, flags); 1097 } 1098 spin_unlock_irqrestore(&p9_poll_lock, flags); 1099 1100 p9_debug(P9_DEBUG_TRANS, "finish\n"); 1101} 1102 1103int p9_trans_fd_init(void) 1104{ 1105 v9fs_register_trans(&p9_tcp_trans); 1106 v9fs_register_trans(&p9_unix_trans); 1107 v9fs_register_trans(&p9_fd_trans); 1108 1109 return 0; 1110} 1111 1112void p9_trans_fd_exit(void) 1113{ 1114 flush_work(&p9_poll_work); 1115 v9fs_unregister_trans(&p9_tcp_trans); 1116 v9fs_unregister_trans(&p9_unix_trans); 1117 v9fs_unregister_trans(&p9_fd_trans); 1118} 1119