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 #include <linux/in.h> 29 #include <linux/module.h> 30 #include <linux/net.h> 31 #include <linux/ipv6.h> 32 #include <linux/kthread.h> 33 #include <linux/errno.h> 34 #include <linux/kernel.h> 35 #include <linux/un.h> 36 #include <linux/uaccess.h> 37 #include <linux/inet.h> 38 #include <linux/idr.h> 39 #include <linux/file.h> 40 #include <linux/parser.h> 41 #include <net/9p/9p.h> 42 #include <net/9p/client.h> 43 #include <net/9p/transport.h> 44 45 #include <linux/syscalls.h> /* killme */ 46 47 #define P9_PORT 564 48 #define MAX_SOCK_BUF (64*1024) 49 #define MAXPOLLWADDR 2 50 51 /** 52 * struct p9_fd_opts - per-transport options 53 * @rfd: file descriptor for reading (trans=fd) 54 * @wfd: file descriptor for writing (trans=fd) 55 * @port: port to connect to (trans=tcp) 56 * 57 */ 58 59 struct p9_fd_opts { 60 int rfd; 61 int wfd; 62 u16 port; 63 }; 64 65 /** 66 * struct p9_trans_fd - transport state 67 * @rd: reference to file to read from 68 * @wr: reference of file to write to 69 * @conn: connection state reference 70 * 71 */ 72 73 struct p9_trans_fd { 74 struct file *rd; 75 struct file *wr; 76 struct p9_conn *conn; 77 }; 78 79 /* 80 * Option Parsing (code inspired by NFS code) 81 * - a little lazy - parse all fd-transport options 82 */ 83 84 enum { 85 /* Options that take integer arguments */ 86 Opt_port, Opt_rfdno, Opt_wfdno, Opt_err, 87 }; 88 89 static const match_table_t tokens = { 90 {Opt_port, "port=%u"}, 91 {Opt_rfdno, "rfdno=%u"}, 92 {Opt_wfdno, "wfdno=%u"}, 93 {Opt_err, NULL}, 94 }; 95 96 enum { 97 Rworksched = 1, /* read work scheduled or running */ 98 Rpending = 2, /* can read */ 99 Wworksched = 4, /* write work scheduled or running */ 100 Wpending = 8, /* can write */ 101 }; 102 103 struct p9_poll_wait { 104 struct p9_conn *conn; 105 wait_queue_t wait; 106 wait_queue_head_t *wait_addr; 107 }; 108 109 /** 110 * struct p9_conn - fd mux connection state information 111 * @mux_list: list link for mux to manage multiple connections (?) 112 * @client: reference to client instance for this connection 113 * @err: error state 114 * @req_list: accounting for requests which have been sent 115 * @unsent_req_list: accounting for requests that haven't been sent 116 * @req: current request being processed (if any) 117 * @tmp_buf: temporary buffer to read in header 118 * @rsize: amount to read for current frame 119 * @rpos: read position in current frame 120 * @rbuf: current read buffer 121 * @wpos: write position for current frame 122 * @wsize: amount of data to write for current frame 123 * @wbuf: current write buffer 124 * @poll_pending_link: pending links to be polled per conn 125 * @poll_wait: array of wait_q's for various worker threads 126 * @pt: poll state 127 * @rq: current read work 128 * @wq: current write work 129 * @wsched: ???? 130 * 131 */ 132 133 struct p9_conn { 134 struct list_head mux_list; 135 struct p9_client *client; 136 int err; 137 struct list_head req_list; 138 struct list_head unsent_req_list; 139 struct p9_req_t *req; 140 char tmp_buf[7]; 141 int rsize; 142 int rpos; 143 char *rbuf; 144 int wpos; 145 int wsize; 146 char *wbuf; 147 struct list_head poll_pending_link; 148 struct p9_poll_wait poll_wait[MAXPOLLWADDR]; 149 poll_table pt; 150 struct work_struct rq; 151 struct work_struct wq; 152 unsigned long wsched; 153 }; 154 155 static DEFINE_SPINLOCK(p9_poll_lock); 156 static LIST_HEAD(p9_poll_pending_list); 157 static struct workqueue_struct *p9_mux_wq; 158 static struct task_struct *p9_poll_task; 159 160 static void p9_mux_poll_stop(struct p9_conn *m) 161 { 162 unsigned long flags; 163 int i; 164 165 for (i = 0; i < ARRAY_SIZE(m->poll_wait); i++) { 166 struct p9_poll_wait *pwait = &m->poll_wait[i]; 167 168 if (pwait->wait_addr) { 169 remove_wait_queue(pwait->wait_addr, &pwait->wait); 170 pwait->wait_addr = NULL; 171 } 172 } 173 174 spin_lock_irqsave(&p9_poll_lock, flags); 175 list_del_init(&m->poll_pending_link); 176 spin_unlock_irqrestore(&p9_poll_lock, flags); 177 } 178 179 /** 180 * p9_conn_cancel - cancel all pending requests with error 181 * @m: mux data 182 * @err: error code 183 * 184 */ 185 186 static void p9_conn_cancel(struct p9_conn *m, int err) 187 { 188 struct p9_req_t *req, *rtmp; 189 unsigned long flags; 190 LIST_HEAD(cancel_list); 191 192 P9_DPRINTK(P9_DEBUG_ERROR, "mux %p err %d\n", m, err); 193 194 spin_lock_irqsave(&m->client->lock, flags); 195 196 if (m->err) { 197 spin_unlock_irqrestore(&m->client->lock, flags); 198 return; 199 } 200 201 m->err = err; 202 203 list_for_each_entry_safe(req, rtmp, &m->req_list, req_list) { 204 req->status = REQ_STATUS_ERROR; 205 if (!req->t_err) 206 req->t_err = err; 207 list_move(&req->req_list, &cancel_list); 208 } 209 list_for_each_entry_safe(req, rtmp, &m->unsent_req_list, req_list) { 210 req->status = REQ_STATUS_ERROR; 211 if (!req->t_err) 212 req->t_err = err; 213 list_move(&req->req_list, &cancel_list); 214 } 215 spin_unlock_irqrestore(&m->client->lock, flags); 216 217 list_for_each_entry_safe(req, rtmp, &cancel_list, req_list) { 218 P9_DPRINTK(P9_DEBUG_ERROR, "call back req %p\n", req); 219 list_del(&req->req_list); 220 p9_client_cb(m->client, req); 221 } 222 } 223 224 static unsigned int 225 p9_fd_poll(struct p9_client *client, struct poll_table_struct *pt) 226 { 227 int ret, n; 228 struct p9_trans_fd *ts = NULL; 229 230 if (client && client->status == Connected) 231 ts = client->trans; 232 233 if (!ts) 234 return -EREMOTEIO; 235 236 if (!ts->rd->f_op || !ts->rd->f_op->poll) 237 return -EIO; 238 239 if (!ts->wr->f_op || !ts->wr->f_op->poll) 240 return -EIO; 241 242 ret = ts->rd->f_op->poll(ts->rd, pt); 243 if (ret < 0) 244 return ret; 245 246 if (ts->rd != ts->wr) { 247 n = ts->wr->f_op->poll(ts->wr, pt); 248 if (n < 0) 249 return n; 250 ret = (ret & ~POLLOUT) | (n & ~POLLIN); 251 } 252 253 return ret; 254 } 255 256 /** 257 * p9_fd_read- read from a fd 258 * @client: client instance 259 * @v: buffer to receive data into 260 * @len: size of receive buffer 261 * 262 */ 263 264 static int p9_fd_read(struct p9_client *client, void *v, int len) 265 { 266 int ret; 267 struct p9_trans_fd *ts = NULL; 268 269 if (client && client->status != Disconnected) 270 ts = client->trans; 271 272 if (!ts) 273 return -EREMOTEIO; 274 275 if (!(ts->rd->f_flags & O_NONBLOCK)) 276 P9_DPRINTK(P9_DEBUG_ERROR, "blocking read ...\n"); 277 278 ret = kernel_read(ts->rd, ts->rd->f_pos, v, len); 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 int n, err; 293 struct p9_conn *m; 294 295 m = container_of(work, struct p9_conn, rq); 296 297 if (m->err < 0) 298 return; 299 300 P9_DPRINTK(P9_DEBUG_TRANS, "start mux %p pos %d\n", m, m->rpos); 301 302 if (!m->rbuf) { 303 m->rbuf = m->tmp_buf; 304 m->rpos = 0; 305 m->rsize = 7; /* start by reading header */ 306 } 307 308 clear_bit(Rpending, &m->wsched); 309 P9_DPRINTK(P9_DEBUG_TRANS, "read mux %p pos %d size: %d = %d\n", m, 310 m->rpos, m->rsize, m->rsize-m->rpos); 311 err = p9_fd_read(m->client, m->rbuf + m->rpos, 312 m->rsize - m->rpos); 313 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p got %d bytes\n", m, err); 314 if (err == -EAGAIN) { 315 clear_bit(Rworksched, &m->wsched); 316 return; 317 } 318 319 if (err <= 0) 320 goto error; 321 322 m->rpos += err; 323 324 if ((!m->req) && (m->rpos == m->rsize)) { /* header read in */ 325 u16 tag; 326 P9_DPRINTK(P9_DEBUG_TRANS, "got new header\n"); 327 328 n = le32_to_cpu(*(__le32 *) m->rbuf); /* read packet size */ 329 if (n >= m->client->msize) { 330 P9_DPRINTK(P9_DEBUG_ERROR, 331 "requested packet size too big: %d\n", n); 332 err = -EIO; 333 goto error; 334 } 335 336 tag = le16_to_cpu(*(__le16 *) (m->rbuf+5)); /* read tag */ 337 P9_DPRINTK(P9_DEBUG_TRANS, 338 "mux %p pkt: size: %d bytes tag: %d\n", m, n, tag); 339 340 m->req = p9_tag_lookup(m->client, tag); 341 if (!m->req || (m->req->status != REQ_STATUS_SENT && 342 m->req->status != REQ_STATUS_FLSH)) { 343 P9_DPRINTK(P9_DEBUG_ERROR, "Unexpected packet tag %d\n", 344 tag); 345 err = -EIO; 346 goto error; 347 } 348 349 if (m->req->rc == NULL) { 350 m->req->rc = kmalloc(sizeof(struct p9_fcall) + 351 m->client->msize, GFP_KERNEL); 352 if (!m->req->rc) { 353 m->req = NULL; 354 err = -ENOMEM; 355 goto error; 356 } 357 } 358 m->rbuf = (char *)m->req->rc + sizeof(struct p9_fcall); 359 memcpy(m->rbuf, m->tmp_buf, m->rsize); 360 m->rsize = n; 361 } 362 363 /* not an else because some packets (like clunk) have no payload */ 364 if ((m->req) && (m->rpos == m->rsize)) { /* packet is read in */ 365 P9_DPRINTK(P9_DEBUG_TRANS, "got new packet\n"); 366 spin_lock(&m->client->lock); 367 if (m->req->status != REQ_STATUS_ERROR) 368 m->req->status = REQ_STATUS_RCVD; 369 list_del(&m->req->req_list); 370 spin_unlock(&m->client->lock); 371 p9_client_cb(m->client, m->req); 372 m->rbuf = NULL; 373 m->rpos = 0; 374 m->rsize = 0; 375 m->req = NULL; 376 } 377 378 if (!list_empty(&m->req_list)) { 379 if (test_and_clear_bit(Rpending, &m->wsched)) 380 n = POLLIN; 381 else 382 n = p9_fd_poll(m->client, NULL); 383 384 if (n & POLLIN) { 385 P9_DPRINTK(P9_DEBUG_TRANS, "sched read work %p\n", m); 386 queue_work(p9_mux_wq, &m->rq); 387 } else 388 clear_bit(Rworksched, &m->wsched); 389 } else 390 clear_bit(Rworksched, &m->wsched); 391 392 return; 393 error: 394 p9_conn_cancel(m, err); 395 clear_bit(Rworksched, &m->wsched); 396 } 397 398 /** 399 * p9_fd_write - write to a socket 400 * @client: client instance 401 * @v: buffer to send data from 402 * @len: size of send buffer 403 * 404 */ 405 406 static int p9_fd_write(struct p9_client *client, void *v, int len) 407 { 408 int ret; 409 mm_segment_t oldfs; 410 struct p9_trans_fd *ts = NULL; 411 412 if (client && client->status != Disconnected) 413 ts = client->trans; 414 415 if (!ts) 416 return -EREMOTEIO; 417 418 if (!(ts->wr->f_flags & O_NONBLOCK)) 419 P9_DPRINTK(P9_DEBUG_ERROR, "blocking write ...\n"); 420 421 oldfs = get_fs(); 422 set_fs(get_ds()); 423 /* The cast to a user pointer is valid due to the set_fs() */ 424 ret = vfs_write(ts->wr, (__force void __user *)v, len, &ts->wr->f_pos); 425 set_fs(oldfs); 426 427 if (ret <= 0 && ret != -ERESTARTSYS && ret != -EAGAIN) 428 client->status = Disconnected; 429 return ret; 430 } 431 432 /** 433 * p9_write_work - called when a transport can send some data 434 * @work: container for work to be done 435 * 436 */ 437 438 static void p9_write_work(struct work_struct *work) 439 { 440 int n, err; 441 struct p9_conn *m; 442 struct p9_req_t *req; 443 444 m = container_of(work, struct p9_conn, wq); 445 446 if (m->err < 0) { 447 clear_bit(Wworksched, &m->wsched); 448 return; 449 } 450 451 if (!m->wsize) { 452 if (list_empty(&m->unsent_req_list)) { 453 clear_bit(Wworksched, &m->wsched); 454 return; 455 } 456 457 spin_lock(&m->client->lock); 458 req = list_entry(m->unsent_req_list.next, struct p9_req_t, 459 req_list); 460 req->status = REQ_STATUS_SENT; 461 P9_DPRINTK(P9_DEBUG_TRANS, "move req %p\n", req); 462 list_move_tail(&req->req_list, &m->req_list); 463 464 m->wbuf = req->tc->sdata; 465 m->wsize = req->tc->size; 466 m->wpos = 0; 467 spin_unlock(&m->client->lock); 468 } 469 470 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p pos %d size %d\n", m, m->wpos, 471 m->wsize); 472 clear_bit(Wpending, &m->wsched); 473 err = p9_fd_write(m->client, m->wbuf + m->wpos, m->wsize - m->wpos); 474 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p sent %d bytes\n", m, err); 475 if (err == -EAGAIN) { 476 clear_bit(Wworksched, &m->wsched); 477 return; 478 } 479 480 if (err < 0) 481 goto error; 482 else if (err == 0) { 483 err = -EREMOTEIO; 484 goto error; 485 } 486 487 m->wpos += err; 488 if (m->wpos == m->wsize) 489 m->wpos = m->wsize = 0; 490 491 if (m->wsize == 0 && !list_empty(&m->unsent_req_list)) { 492 if (test_and_clear_bit(Wpending, &m->wsched)) 493 n = POLLOUT; 494 else 495 n = p9_fd_poll(m->client, NULL); 496 497 if (n & POLLOUT) { 498 P9_DPRINTK(P9_DEBUG_TRANS, "sched write work %p\n", m); 499 queue_work(p9_mux_wq, &m->wq); 500 } else 501 clear_bit(Wworksched, &m->wsched); 502 } else 503 clear_bit(Wworksched, &m->wsched); 504 505 return; 506 507 error: 508 p9_conn_cancel(m, err); 509 clear_bit(Wworksched, &m->wsched); 510 } 511 512 static int p9_pollwake(wait_queue_t *wait, unsigned mode, int sync, void *key) 513 { 514 struct p9_poll_wait *pwait = 515 container_of(wait, struct p9_poll_wait, wait); 516 struct p9_conn *m = pwait->conn; 517 unsigned long flags; 518 DECLARE_WAITQUEUE(dummy_wait, p9_poll_task); 519 520 spin_lock_irqsave(&p9_poll_lock, flags); 521 if (list_empty(&m->poll_pending_link)) 522 list_add_tail(&m->poll_pending_link, &p9_poll_pending_list); 523 spin_unlock_irqrestore(&p9_poll_lock, flags); 524 525 /* perform the default wake up operation */ 526 return default_wake_function(&dummy_wait, mode, sync, key); 527 } 528 529 /** 530 * p9_pollwait - add poll task to the wait queue 531 * @filp: file pointer being polled 532 * @wait_address: wait_q to block on 533 * @p: poll state 534 * 535 * called by files poll operation to add v9fs-poll task to files wait queue 536 */ 537 538 static void 539 p9_pollwait(struct file *filp, wait_queue_head_t *wait_address, poll_table *p) 540 { 541 struct p9_conn *m = container_of(p, struct p9_conn, pt); 542 struct p9_poll_wait *pwait = NULL; 543 int i; 544 545 for (i = 0; i < ARRAY_SIZE(m->poll_wait); i++) { 546 if (m->poll_wait[i].wait_addr == NULL) { 547 pwait = &m->poll_wait[i]; 548 break; 549 } 550 } 551 552 if (!pwait) { 553 P9_DPRINTK(P9_DEBUG_ERROR, "not enough wait_address slots\n"); 554 return; 555 } 556 557 pwait->conn = m; 558 pwait->wait_addr = wait_address; 559 init_waitqueue_func_entry(&pwait->wait, p9_pollwake); 560 add_wait_queue(wait_address, &pwait->wait); 561 } 562 563 /** 564 * p9_conn_create - allocate and initialize the per-session mux data 565 * @client: client instance 566 * 567 * Note: Creates the polling task if this is the first session. 568 */ 569 570 static struct p9_conn *p9_conn_create(struct p9_client *client) 571 { 572 int n; 573 struct p9_conn *m; 574 575 P9_DPRINTK(P9_DEBUG_TRANS, "client %p msize %d\n", client, 576 client->msize); 577 m = kzalloc(sizeof(struct p9_conn), GFP_KERNEL); 578 if (!m) 579 return ERR_PTR(-ENOMEM); 580 581 INIT_LIST_HEAD(&m->mux_list); 582 m->client = client; 583 584 INIT_LIST_HEAD(&m->req_list); 585 INIT_LIST_HEAD(&m->unsent_req_list); 586 INIT_WORK(&m->rq, p9_read_work); 587 INIT_WORK(&m->wq, p9_write_work); 588 INIT_LIST_HEAD(&m->poll_pending_link); 589 init_poll_funcptr(&m->pt, p9_pollwait); 590 591 n = p9_fd_poll(client, &m->pt); 592 if (n & POLLIN) { 593 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p can read\n", m); 594 set_bit(Rpending, &m->wsched); 595 } 596 597 if (n & POLLOUT) { 598 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p can write\n", m); 599 set_bit(Wpending, &m->wsched); 600 } 601 602 return m; 603 } 604 605 /** 606 * p9_poll_mux - polls a mux and schedules read or write works if necessary 607 * @m: connection to poll 608 * 609 */ 610 611 static void p9_poll_mux(struct p9_conn *m) 612 { 613 int n; 614 615 if (m->err < 0) 616 return; 617 618 n = p9_fd_poll(m->client, NULL); 619 if (n < 0 || n & (POLLERR | POLLHUP | POLLNVAL)) { 620 P9_DPRINTK(P9_DEBUG_TRANS, "error mux %p err %d\n", m, n); 621 if (n >= 0) 622 n = -ECONNRESET; 623 p9_conn_cancel(m, n); 624 } 625 626 if (n & POLLIN) { 627 set_bit(Rpending, &m->wsched); 628 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p can read\n", m); 629 if (!test_and_set_bit(Rworksched, &m->wsched)) { 630 P9_DPRINTK(P9_DEBUG_TRANS, "sched read work %p\n", m); 631 queue_work(p9_mux_wq, &m->rq); 632 } 633 } 634 635 if (n & POLLOUT) { 636 set_bit(Wpending, &m->wsched); 637 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p can write\n", m); 638 if ((m->wsize || !list_empty(&m->unsent_req_list)) && 639 !test_and_set_bit(Wworksched, &m->wsched)) { 640 P9_DPRINTK(P9_DEBUG_TRANS, "sched write work %p\n", m); 641 queue_work(p9_mux_wq, &m->wq); 642 } 643 } 644 } 645 646 /** 647 * p9_fd_request - send 9P request 648 * The function can sleep until the request is scheduled for sending. 649 * The function can be interrupted. Return from the function is not 650 * a guarantee that the request is sent successfully. 651 * 652 * @client: client instance 653 * @req: request to be sent 654 * 655 */ 656 657 static int p9_fd_request(struct p9_client *client, struct p9_req_t *req) 658 { 659 int n; 660 struct p9_trans_fd *ts = client->trans; 661 struct p9_conn *m = ts->conn; 662 663 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p task %p tcall %p id %d\n", m, 664 current, req->tc, req->tc->id); 665 if (m->err < 0) 666 return m->err; 667 668 spin_lock(&client->lock); 669 req->status = REQ_STATUS_UNSENT; 670 list_add_tail(&req->req_list, &m->unsent_req_list); 671 spin_unlock(&client->lock); 672 673 if (test_and_clear_bit(Wpending, &m->wsched)) 674 n = POLLOUT; 675 else 676 n = p9_fd_poll(m->client, NULL); 677 678 if (n & POLLOUT && !test_and_set_bit(Wworksched, &m->wsched)) 679 queue_work(p9_mux_wq, &m->wq); 680 681 return 0; 682 } 683 684 static int p9_fd_cancel(struct p9_client *client, struct p9_req_t *req) 685 { 686 int ret = 1; 687 688 P9_DPRINTK(P9_DEBUG_TRANS, "client %p req %p\n", client, req); 689 690 spin_lock(&client->lock); 691 692 if (req->status == REQ_STATUS_UNSENT) { 693 list_del(&req->req_list); 694 req->status = REQ_STATUS_FLSHD; 695 ret = 0; 696 } else if (req->status == REQ_STATUS_SENT) 697 req->status = REQ_STATUS_FLSH; 698 699 spin_unlock(&client->lock); 700 701 return ret; 702 } 703 704 /** 705 * parse_opts - parse mount options into p9_fd_opts structure 706 * @params: options string passed from mount 707 * @opts: fd transport-specific structure to parse options into 708 * 709 * Returns 0 upon success, -ERRNO upon failure 710 */ 711 712 static int parse_opts(char *params, struct p9_fd_opts *opts) 713 { 714 char *p; 715 substring_t args[MAX_OPT_ARGS]; 716 int option; 717 char *options; 718 int ret; 719 720 opts->port = P9_PORT; 721 opts->rfd = ~0; 722 opts->wfd = ~0; 723 724 if (!params) 725 return 0; 726 727 options = kstrdup(params, GFP_KERNEL); 728 if (!options) { 729 P9_DPRINTK(P9_DEBUG_ERROR, 730 "failed to allocate copy of option string\n"); 731 return -ENOMEM; 732 } 733 734 while ((p = strsep(&options, ",")) != NULL) { 735 int token; 736 int r; 737 if (!*p) 738 continue; 739 token = match_token(p, tokens, args); 740 if (token != Opt_err) { 741 r = match_int(&args[0], &option); 742 if (r < 0) { 743 P9_DPRINTK(P9_DEBUG_ERROR, 744 "integer field, but no integer?\n"); 745 ret = r; 746 continue; 747 } 748 } 749 switch (token) { 750 case Opt_port: 751 opts->port = option; 752 break; 753 case Opt_rfdno: 754 opts->rfd = option; 755 break; 756 case Opt_wfdno: 757 opts->wfd = option; 758 break; 759 default: 760 continue; 761 } 762 } 763 kfree(options); 764 return 0; 765 } 766 767 static int p9_fd_open(struct p9_client *client, int rfd, int wfd) 768 { 769 struct p9_trans_fd *ts = kmalloc(sizeof(struct p9_trans_fd), 770 GFP_KERNEL); 771 if (!ts) 772 return -ENOMEM; 773 774 ts->rd = fget(rfd); 775 ts->wr = fget(wfd); 776 if (!ts->rd || !ts->wr) { 777 if (ts->rd) 778 fput(ts->rd); 779 if (ts->wr) 780 fput(ts->wr); 781 kfree(ts); 782 return -EIO; 783 } 784 785 client->trans = ts; 786 client->status = Connected; 787 788 return 0; 789 } 790 791 static int p9_socket_open(struct p9_client *client, struct socket *csocket) 792 { 793 struct p9_trans_fd *p; 794 int ret, fd; 795 796 p = kmalloc(sizeof(struct p9_trans_fd), GFP_KERNEL); 797 if (!p) 798 return -ENOMEM; 799 800 csocket->sk->sk_allocation = GFP_NOIO; 801 fd = sock_map_fd(csocket, 0); 802 if (fd < 0) { 803 P9_EPRINTK(KERN_ERR, "p9_socket_open: failed to map fd\n"); 804 sock_release(csocket); 805 kfree(p); 806 return fd; 807 } 808 809 get_file(csocket->file); 810 get_file(csocket->file); 811 p->wr = p->rd = csocket->file; 812 client->trans = p; 813 client->status = Connected; 814 815 sys_close(fd); /* still racy */ 816 817 p->rd->f_flags |= O_NONBLOCK; 818 819 p->conn = p9_conn_create(client); 820 if (IS_ERR(p->conn)) { 821 ret = PTR_ERR(p->conn); 822 p->conn = NULL; 823 kfree(p); 824 sockfd_put(csocket); 825 sockfd_put(csocket); 826 return ret; 827 } 828 return 0; 829 } 830 831 /** 832 * p9_mux_destroy - cancels all pending requests and frees mux resources 833 * @m: mux to destroy 834 * 835 */ 836 837 static void p9_conn_destroy(struct p9_conn *m) 838 { 839 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p prev %p next %p\n", m, 840 m->mux_list.prev, m->mux_list.next); 841 842 p9_mux_poll_stop(m); 843 cancel_work_sync(&m->rq); 844 cancel_work_sync(&m->wq); 845 846 p9_conn_cancel(m, -ECONNRESET); 847 848 m->client = NULL; 849 kfree(m); 850 } 851 852 /** 853 * p9_fd_close - shutdown file descriptor transport 854 * @client: client instance 855 * 856 */ 857 858 static void p9_fd_close(struct p9_client *client) 859 { 860 struct p9_trans_fd *ts; 861 862 if (!client) 863 return; 864 865 ts = client->trans; 866 if (!ts) 867 return; 868 869 client->status = Disconnected; 870 871 p9_conn_destroy(ts->conn); 872 873 if (ts->rd) 874 fput(ts->rd); 875 if (ts->wr) 876 fput(ts->wr); 877 878 kfree(ts); 879 } 880 881 /* 882 * stolen from NFS - maybe should be made a generic function? 883 */ 884 static inline int valid_ipaddr4(const char *buf) 885 { 886 int rc, count, in[4]; 887 888 rc = sscanf(buf, "%d.%d.%d.%d", &in[0], &in[1], &in[2], &in[3]); 889 if (rc != 4) 890 return -EINVAL; 891 for (count = 0; count < 4; count++) { 892 if (in[count] > 255) 893 return -EINVAL; 894 } 895 return 0; 896 } 897 898 static int 899 p9_fd_create_tcp(struct p9_client *client, const char *addr, char *args) 900 { 901 int err; 902 struct socket *csocket; 903 struct sockaddr_in sin_server; 904 struct p9_fd_opts opts; 905 906 err = parse_opts(args, &opts); 907 if (err < 0) 908 return err; 909 910 if (valid_ipaddr4(addr) < 0) 911 return -EINVAL; 912 913 csocket = NULL; 914 915 sin_server.sin_family = AF_INET; 916 sin_server.sin_addr.s_addr = in_aton(addr); 917 sin_server.sin_port = htons(opts.port); 918 err = sock_create_kern(PF_INET, SOCK_STREAM, IPPROTO_TCP, &csocket); 919 920 if (err) { 921 P9_EPRINTK(KERN_ERR, "p9_trans_tcp: problem creating socket\n"); 922 return err; 923 } 924 925 err = csocket->ops->connect(csocket, 926 (struct sockaddr *)&sin_server, 927 sizeof(struct sockaddr_in), 0); 928 if (err < 0) { 929 P9_EPRINTK(KERN_ERR, 930 "p9_trans_tcp: problem connecting socket to %s\n", 931 addr); 932 sock_release(csocket); 933 return err; 934 } 935 936 return p9_socket_open(client, csocket); 937 } 938 939 static int 940 p9_fd_create_unix(struct p9_client *client, const char *addr, char *args) 941 { 942 int err; 943 struct socket *csocket; 944 struct sockaddr_un sun_server; 945 946 csocket = NULL; 947 948 if (strlen(addr) > UNIX_PATH_MAX) { 949 P9_EPRINTK(KERN_ERR, "p9_trans_unix: address too long: %s\n", 950 addr); 951 return -ENAMETOOLONG; 952 } 953 954 sun_server.sun_family = PF_UNIX; 955 strcpy(sun_server.sun_path, addr); 956 err = sock_create_kern(PF_UNIX, SOCK_STREAM, 0, &csocket); 957 if (err < 0) { 958 P9_EPRINTK(KERN_ERR, "p9_trans_unix: problem creating socket\n"); 959 return err; 960 } 961 err = csocket->ops->connect(csocket, (struct sockaddr *)&sun_server, 962 sizeof(struct sockaddr_un) - 1, 0); 963 if (err < 0) { 964 P9_EPRINTK(KERN_ERR, 965 "p9_trans_unix: problem connecting socket: %s: %d\n", 966 addr, err); 967 sock_release(csocket); 968 return err; 969 } 970 971 return p9_socket_open(client, csocket); 972 } 973 974 static int 975 p9_fd_create(struct p9_client *client, const char *addr, char *args) 976 { 977 int err; 978 struct p9_fd_opts opts; 979 struct p9_trans_fd *p; 980 981 parse_opts(args, &opts); 982 983 if (opts.rfd == ~0 || opts.wfd == ~0) { 984 printk(KERN_ERR "v9fs: Insufficient options for proto=fd\n"); 985 return -ENOPROTOOPT; 986 } 987 988 err = p9_fd_open(client, opts.rfd, opts.wfd); 989 if (err < 0) 990 return err; 991 992 p = (struct p9_trans_fd *) client->trans; 993 p->conn = p9_conn_create(client); 994 if (IS_ERR(p->conn)) { 995 err = PTR_ERR(p->conn); 996 p->conn = NULL; 997 fput(p->rd); 998 fput(p->wr); 999 return err; 1000 } 1001 1002 return 0; 1003 } 1004 1005 static struct p9_trans_module p9_tcp_trans = { 1006 .name = "tcp", 1007 .maxsize = MAX_SOCK_BUF, 1008 .def = 1, 1009 .create = p9_fd_create_tcp, 1010 .close = p9_fd_close, 1011 .request = p9_fd_request, 1012 .cancel = p9_fd_cancel, 1013 .owner = THIS_MODULE, 1014 }; 1015 1016 static struct p9_trans_module p9_unix_trans = { 1017 .name = "unix", 1018 .maxsize = MAX_SOCK_BUF, 1019 .def = 0, 1020 .create = p9_fd_create_unix, 1021 .close = p9_fd_close, 1022 .request = p9_fd_request, 1023 .cancel = p9_fd_cancel, 1024 .owner = THIS_MODULE, 1025 }; 1026 1027 static struct p9_trans_module p9_fd_trans = { 1028 .name = "fd", 1029 .maxsize = MAX_SOCK_BUF, 1030 .def = 0, 1031 .create = p9_fd_create, 1032 .close = p9_fd_close, 1033 .request = p9_fd_request, 1034 .cancel = p9_fd_cancel, 1035 .owner = THIS_MODULE, 1036 }; 1037 1038 /** 1039 * p9_poll_proc - poll worker thread 1040 * @a: thread state and arguments 1041 * 1042 * polls all v9fs transports for new events and queues the appropriate 1043 * work to the work queue 1044 * 1045 */ 1046 1047 static int p9_poll_proc(void *a) 1048 { 1049 unsigned long flags; 1050 1051 P9_DPRINTK(P9_DEBUG_TRANS, "start %p\n", current); 1052 repeat: 1053 spin_lock_irqsave(&p9_poll_lock, flags); 1054 while (!list_empty(&p9_poll_pending_list)) { 1055 struct p9_conn *conn = list_first_entry(&p9_poll_pending_list, 1056 struct p9_conn, 1057 poll_pending_link); 1058 list_del_init(&conn->poll_pending_link); 1059 spin_unlock_irqrestore(&p9_poll_lock, flags); 1060 1061 p9_poll_mux(conn); 1062 1063 spin_lock_irqsave(&p9_poll_lock, flags); 1064 } 1065 spin_unlock_irqrestore(&p9_poll_lock, flags); 1066 1067 set_current_state(TASK_INTERRUPTIBLE); 1068 if (list_empty(&p9_poll_pending_list)) { 1069 P9_DPRINTK(P9_DEBUG_TRANS, "sleeping...\n"); 1070 schedule(); 1071 } 1072 __set_current_state(TASK_RUNNING); 1073 1074 if (!kthread_should_stop()) 1075 goto repeat; 1076 1077 P9_DPRINTK(P9_DEBUG_TRANS, "finish\n"); 1078 return 0; 1079 } 1080 1081 int p9_trans_fd_init(void) 1082 { 1083 p9_mux_wq = create_workqueue("v9fs"); 1084 if (!p9_mux_wq) { 1085 printk(KERN_WARNING "v9fs: mux: creating workqueue failed\n"); 1086 return -ENOMEM; 1087 } 1088 1089 p9_poll_task = kthread_run(p9_poll_proc, NULL, "v9fs-poll"); 1090 if (IS_ERR(p9_poll_task)) { 1091 destroy_workqueue(p9_mux_wq); 1092 printk(KERN_WARNING "v9fs: mux: creating poll task failed\n"); 1093 return PTR_ERR(p9_poll_task); 1094 } 1095 1096 v9fs_register_trans(&p9_tcp_trans); 1097 v9fs_register_trans(&p9_unix_trans); 1098 v9fs_register_trans(&p9_fd_trans); 1099 1100 return 0; 1101 } 1102 1103 void p9_trans_fd_exit(void) 1104 { 1105 kthread_stop(p9_poll_task); 1106 v9fs_unregister_trans(&p9_tcp_trans); 1107 v9fs_unregister_trans(&p9_unix_trans); 1108 v9fs_unregister_trans(&p9_fd_trans); 1109 1110 destroy_workqueue(p9_mux_wq); 1111 } 1112