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 #define P9_PORT 564 46 #define MAX_SOCK_BUF (64*1024) 47 #define MAXPOLLWADDR 2 48 49 /** 50 * struct p9_fd_opts - per-transport options 51 * @rfd: file descriptor for reading (trans=fd) 52 * @wfd: file descriptor for writing (trans=fd) 53 * @port: port to connect to (trans=tcp) 54 * 55 */ 56 57 struct p9_fd_opts { 58 int rfd; 59 int wfd; 60 u16 port; 61 }; 62 63 /** 64 * struct p9_trans_fd - transport state 65 * @rd: reference to file to read from 66 * @wr: reference of file to write to 67 * @conn: connection state reference 68 * 69 */ 70 71 struct p9_trans_fd { 72 struct file *rd; 73 struct file *wr; 74 struct p9_conn *conn; 75 }; 76 77 /* 78 * Option Parsing (code inspired by NFS code) 79 * - a little lazy - parse all fd-transport options 80 */ 81 82 enum { 83 /* Options that take integer arguments */ 84 Opt_port, Opt_rfdno, Opt_wfdno, Opt_err, 85 }; 86 87 static const match_table_t tokens = { 88 {Opt_port, "port=%u"}, 89 {Opt_rfdno, "rfdno=%u"}, 90 {Opt_wfdno, "wfdno=%u"}, 91 {Opt_err, NULL}, 92 }; 93 94 enum { 95 Rworksched = 1, /* read work scheduled or running */ 96 Rpending = 2, /* can read */ 97 Wworksched = 4, /* write work scheduled or running */ 98 Wpending = 8, /* can write */ 99 }; 100 101 struct p9_poll_wait { 102 struct p9_conn *conn; 103 wait_queue_t wait; 104 wait_queue_head_t *wait_addr; 105 }; 106 107 /** 108 * struct p9_conn - fd mux connection state information 109 * @mux_list: list link for mux to manage multiple connections (?) 110 * @client: reference to client instance for this connection 111 * @err: error state 112 * @req_list: accounting for requests which have been sent 113 * @unsent_req_list: accounting for requests that haven't been sent 114 * @req: current request being processed (if any) 115 * @tmp_buf: temporary buffer to read in header 116 * @rsize: amount to read for current frame 117 * @rpos: read position in current frame 118 * @rbuf: current read buffer 119 * @wpos: write position for current frame 120 * @wsize: amount of data to write for current frame 121 * @wbuf: current write buffer 122 * @poll_pending_link: pending links to be polled per conn 123 * @poll_wait: array of wait_q's for various worker threads 124 * @pt: poll state 125 * @rq: current read work 126 * @wq: current write work 127 * @wsched: ???? 128 * 129 */ 130 131 struct p9_conn { 132 struct list_head mux_list; 133 struct p9_client *client; 134 int err; 135 struct list_head req_list; 136 struct list_head unsent_req_list; 137 struct p9_req_t *req; 138 char tmp_buf[7]; 139 int rsize; 140 int rpos; 141 char *rbuf; 142 int wpos; 143 int wsize; 144 char *wbuf; 145 struct list_head poll_pending_link; 146 struct p9_poll_wait poll_wait[MAXPOLLWADDR]; 147 poll_table pt; 148 struct work_struct rq; 149 struct work_struct wq; 150 unsigned long wsched; 151 }; 152 153 static DEFINE_SPINLOCK(p9_poll_lock); 154 static LIST_HEAD(p9_poll_pending_list); 155 static struct workqueue_struct *p9_mux_wq; 156 static struct task_struct *p9_poll_task; 157 158 static void p9_mux_poll_stop(struct p9_conn *m) 159 { 160 unsigned long flags; 161 int i; 162 163 for (i = 0; i < ARRAY_SIZE(m->poll_wait); i++) { 164 struct p9_poll_wait *pwait = &m->poll_wait[i]; 165 166 if (pwait->wait_addr) { 167 remove_wait_queue(pwait->wait_addr, &pwait->wait); 168 pwait->wait_addr = NULL; 169 } 170 } 171 172 spin_lock_irqsave(&p9_poll_lock, flags); 173 list_del_init(&m->poll_pending_link); 174 spin_unlock_irqrestore(&p9_poll_lock, flags); 175 } 176 177 /** 178 * p9_conn_cancel - cancel all pending requests with error 179 * @m: mux data 180 * @err: error code 181 * 182 */ 183 184 static void p9_conn_cancel(struct p9_conn *m, int err) 185 { 186 struct p9_req_t *req, *rtmp; 187 unsigned long flags; 188 LIST_HEAD(cancel_list); 189 190 P9_DPRINTK(P9_DEBUG_ERROR, "mux %p err %d\n", m, err); 191 192 spin_lock_irqsave(&m->client->lock, flags); 193 194 if (m->err) { 195 spin_unlock_irqrestore(&m->client->lock, flags); 196 return; 197 } 198 199 m->err = err; 200 201 list_for_each_entry_safe(req, rtmp, &m->req_list, req_list) { 202 req->status = REQ_STATUS_ERROR; 203 if (!req->t_err) 204 req->t_err = err; 205 list_move(&req->req_list, &cancel_list); 206 } 207 list_for_each_entry_safe(req, rtmp, &m->unsent_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 spin_unlock_irqrestore(&m->client->lock, flags); 214 215 list_for_each_entry_safe(req, rtmp, &cancel_list, req_list) { 216 P9_DPRINTK(P9_DEBUG_ERROR, "call back req %p\n", req); 217 list_del(&req->req_list); 218 p9_client_cb(m->client, req); 219 } 220 } 221 222 static unsigned int 223 p9_fd_poll(struct p9_client *client, struct poll_table_struct *pt) 224 { 225 int ret, n; 226 struct p9_trans_fd *ts = NULL; 227 228 if (client && client->status == Connected) 229 ts = client->trans; 230 231 if (!ts) 232 return -EREMOTEIO; 233 234 if (!ts->rd->f_op || !ts->rd->f_op->poll) 235 return -EIO; 236 237 if (!ts->wr->f_op || !ts->wr->f_op->poll) 238 return -EIO; 239 240 ret = ts->rd->f_op->poll(ts->rd, pt); 241 if (ret < 0) 242 return ret; 243 244 if (ts->rd != ts->wr) { 245 n = ts->wr->f_op->poll(ts->wr, pt); 246 if (n < 0) 247 return n; 248 ret = (ret & ~POLLOUT) | (n & ~POLLIN); 249 } 250 251 return ret; 252 } 253 254 /** 255 * p9_fd_read- read from a fd 256 * @client: client instance 257 * @v: buffer to receive data into 258 * @len: size of receive buffer 259 * 260 */ 261 262 static int p9_fd_read(struct p9_client *client, void *v, int len) 263 { 264 int ret; 265 struct p9_trans_fd *ts = NULL; 266 267 if (client && client->status != Disconnected) 268 ts = client->trans; 269 270 if (!ts) 271 return -EREMOTEIO; 272 273 if (!(ts->rd->f_flags & O_NONBLOCK)) 274 P9_DPRINTK(P9_DEBUG_ERROR, "blocking read ...\n"); 275 276 ret = kernel_read(ts->rd, ts->rd->f_pos, v, len); 277 if (ret <= 0 && ret != -ERESTARTSYS && ret != -EAGAIN) 278 client->status = Disconnected; 279 return ret; 280 } 281 282 /** 283 * p9_read_work - called when there is some data to be read from a transport 284 * @work: container of work to be done 285 * 286 */ 287 288 static void p9_read_work(struct work_struct *work) 289 { 290 int n, err; 291 struct p9_conn *m; 292 293 m = container_of(work, struct p9_conn, rq); 294 295 if (m->err < 0) 296 return; 297 298 P9_DPRINTK(P9_DEBUG_TRANS, "start mux %p pos %d\n", m, m->rpos); 299 300 if (!m->rbuf) { 301 m->rbuf = m->tmp_buf; 302 m->rpos = 0; 303 m->rsize = 7; /* start by reading header */ 304 } 305 306 clear_bit(Rpending, &m->wsched); 307 P9_DPRINTK(P9_DEBUG_TRANS, "read mux %p pos %d size: %d = %d\n", m, 308 m->rpos, m->rsize, m->rsize-m->rpos); 309 err = p9_fd_read(m->client, m->rbuf + m->rpos, 310 m->rsize - m->rpos); 311 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p got %d bytes\n", m, err); 312 if (err == -EAGAIN) { 313 clear_bit(Rworksched, &m->wsched); 314 return; 315 } 316 317 if (err <= 0) 318 goto error; 319 320 m->rpos += err; 321 322 if ((!m->req) && (m->rpos == m->rsize)) { /* header read in */ 323 u16 tag; 324 P9_DPRINTK(P9_DEBUG_TRANS, "got new header\n"); 325 326 n = le32_to_cpu(*(__le32 *) m->rbuf); /* read packet size */ 327 if (n >= m->client->msize) { 328 P9_DPRINTK(P9_DEBUG_ERROR, 329 "requested packet size too big: %d\n", n); 330 err = -EIO; 331 goto error; 332 } 333 334 tag = le16_to_cpu(*(__le16 *) (m->rbuf+5)); /* read tag */ 335 P9_DPRINTK(P9_DEBUG_TRANS, 336 "mux %p pkt: size: %d bytes tag: %d\n", m, n, tag); 337 338 m->req = p9_tag_lookup(m->client, tag); 339 if (!m->req || (m->req->status != REQ_STATUS_SENT && 340 m->req->status != REQ_STATUS_FLSH)) { 341 P9_DPRINTK(P9_DEBUG_ERROR, "Unexpected packet tag %d\n", 342 tag); 343 err = -EIO; 344 goto error; 345 } 346 347 if (m->req->rc == NULL) { 348 m->req->rc = kmalloc(sizeof(struct p9_fcall) + 349 m->client->msize, GFP_KERNEL); 350 if (!m->req->rc) { 351 m->req = NULL; 352 err = -ENOMEM; 353 goto error; 354 } 355 } 356 m->rbuf = (char *)m->req->rc + sizeof(struct p9_fcall); 357 memcpy(m->rbuf, m->tmp_buf, m->rsize); 358 m->rsize = n; 359 } 360 361 /* not an else because some packets (like clunk) have no payload */ 362 if ((m->req) && (m->rpos == m->rsize)) { /* packet is read in */ 363 P9_DPRINTK(P9_DEBUG_TRANS, "got new packet\n"); 364 spin_lock(&m->client->lock); 365 if (m->req->status != REQ_STATUS_ERROR) 366 m->req->status = REQ_STATUS_RCVD; 367 list_del(&m->req->req_list); 368 spin_unlock(&m->client->lock); 369 p9_client_cb(m->client, m->req); 370 m->rbuf = NULL; 371 m->rpos = 0; 372 m->rsize = 0; 373 m->req = NULL; 374 } 375 376 if (!list_empty(&m->req_list)) { 377 if (test_and_clear_bit(Rpending, &m->wsched)) 378 n = POLLIN; 379 else 380 n = p9_fd_poll(m->client, NULL); 381 382 if (n & POLLIN) { 383 P9_DPRINTK(P9_DEBUG_TRANS, "sched read work %p\n", m); 384 queue_work(p9_mux_wq, &m->rq); 385 } else 386 clear_bit(Rworksched, &m->wsched); 387 } else 388 clear_bit(Rworksched, &m->wsched); 389 390 return; 391 error: 392 p9_conn_cancel(m, err); 393 clear_bit(Rworksched, &m->wsched); 394 } 395 396 /** 397 * p9_fd_write - write to a socket 398 * @client: client instance 399 * @v: buffer to send data from 400 * @len: size of send buffer 401 * 402 */ 403 404 static int p9_fd_write(struct p9_client *client, void *v, int len) 405 { 406 int ret; 407 mm_segment_t oldfs; 408 struct p9_trans_fd *ts = NULL; 409 410 if (client && client->status != Disconnected) 411 ts = client->trans; 412 413 if (!ts) 414 return -EREMOTEIO; 415 416 if (!(ts->wr->f_flags & O_NONBLOCK)) 417 P9_DPRINTK(P9_DEBUG_ERROR, "blocking write ...\n"); 418 419 oldfs = get_fs(); 420 set_fs(get_ds()); 421 /* The cast to a user pointer is valid due to the set_fs() */ 422 ret = vfs_write(ts->wr, (__force void __user *)v, len, &ts->wr->f_pos); 423 set_fs(oldfs); 424 425 if (ret <= 0 && ret != -ERESTARTSYS && ret != -EAGAIN) 426 client->status = Disconnected; 427 return ret; 428 } 429 430 /** 431 * p9_write_work - called when a transport can send some data 432 * @work: container for work to be done 433 * 434 */ 435 436 static void p9_write_work(struct work_struct *work) 437 { 438 int n, err; 439 struct p9_conn *m; 440 struct p9_req_t *req; 441 442 m = container_of(work, struct p9_conn, wq); 443 444 if (m->err < 0) { 445 clear_bit(Wworksched, &m->wsched); 446 return; 447 } 448 449 if (!m->wsize) { 450 if (list_empty(&m->unsent_req_list)) { 451 clear_bit(Wworksched, &m->wsched); 452 return; 453 } 454 455 spin_lock(&m->client->lock); 456 req = list_entry(m->unsent_req_list.next, struct p9_req_t, 457 req_list); 458 req->status = REQ_STATUS_SENT; 459 P9_DPRINTK(P9_DEBUG_TRANS, "move req %p\n", req); 460 list_move_tail(&req->req_list, &m->req_list); 461 462 m->wbuf = req->tc->sdata; 463 m->wsize = req->tc->size; 464 m->wpos = 0; 465 spin_unlock(&m->client->lock); 466 } 467 468 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p pos %d size %d\n", m, m->wpos, 469 m->wsize); 470 clear_bit(Wpending, &m->wsched); 471 err = p9_fd_write(m->client, m->wbuf + m->wpos, m->wsize - m->wpos); 472 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p sent %d bytes\n", m, err); 473 if (err == -EAGAIN) { 474 clear_bit(Wworksched, &m->wsched); 475 return; 476 } 477 478 if (err < 0) 479 goto error; 480 else if (err == 0) { 481 err = -EREMOTEIO; 482 goto error; 483 } 484 485 m->wpos += err; 486 if (m->wpos == m->wsize) 487 m->wpos = m->wsize = 0; 488 489 if (m->wsize == 0 && !list_empty(&m->unsent_req_list)) { 490 if (test_and_clear_bit(Wpending, &m->wsched)) 491 n = POLLOUT; 492 else 493 n = p9_fd_poll(m->client, NULL); 494 495 if (n & POLLOUT) { 496 P9_DPRINTK(P9_DEBUG_TRANS, "sched write work %p\n", m); 497 queue_work(p9_mux_wq, &m->wq); 498 } else 499 clear_bit(Wworksched, &m->wsched); 500 } else 501 clear_bit(Wworksched, &m->wsched); 502 503 return; 504 505 error: 506 p9_conn_cancel(m, err); 507 clear_bit(Wworksched, &m->wsched); 508 } 509 510 static int p9_pollwake(wait_queue_t *wait, unsigned mode, int sync, void *key) 511 { 512 struct p9_poll_wait *pwait = 513 container_of(wait, struct p9_poll_wait, wait); 514 struct p9_conn *m = pwait->conn; 515 unsigned long flags; 516 DECLARE_WAITQUEUE(dummy_wait, p9_poll_task); 517 518 spin_lock_irqsave(&p9_poll_lock, flags); 519 if (list_empty(&m->poll_pending_link)) 520 list_add_tail(&m->poll_pending_link, &p9_poll_pending_list); 521 spin_unlock_irqrestore(&p9_poll_lock, flags); 522 523 /* perform the default wake up operation */ 524 return default_wake_function(&dummy_wait, mode, sync, key); 525 } 526 527 /** 528 * p9_pollwait - add poll task to the wait queue 529 * @filp: file pointer being polled 530 * @wait_address: wait_q to block on 531 * @p: poll state 532 * 533 * called by files poll operation to add v9fs-poll task to files wait queue 534 */ 535 536 static void 537 p9_pollwait(struct file *filp, wait_queue_head_t *wait_address, poll_table *p) 538 { 539 struct p9_conn *m = container_of(p, struct p9_conn, pt); 540 struct p9_poll_wait *pwait = NULL; 541 int i; 542 543 for (i = 0; i < ARRAY_SIZE(m->poll_wait); i++) { 544 if (m->poll_wait[i].wait_addr == NULL) { 545 pwait = &m->poll_wait[i]; 546 break; 547 } 548 } 549 550 if (!pwait) { 551 P9_DPRINTK(P9_DEBUG_ERROR, "not enough wait_address slots\n"); 552 return; 553 } 554 555 pwait->conn = m; 556 pwait->wait_addr = wait_address; 557 init_waitqueue_func_entry(&pwait->wait, p9_pollwake); 558 add_wait_queue(wait_address, &pwait->wait); 559 } 560 561 /** 562 * p9_conn_create - allocate and initialize the per-session mux data 563 * @client: client instance 564 * 565 * Note: Creates the polling task if this is the first session. 566 */ 567 568 static struct p9_conn *p9_conn_create(struct p9_client *client) 569 { 570 int n; 571 struct p9_conn *m; 572 573 P9_DPRINTK(P9_DEBUG_TRANS, "client %p msize %d\n", client, 574 client->msize); 575 m = kzalloc(sizeof(struct p9_conn), GFP_KERNEL); 576 if (!m) 577 return ERR_PTR(-ENOMEM); 578 579 INIT_LIST_HEAD(&m->mux_list); 580 m->client = client; 581 582 INIT_LIST_HEAD(&m->req_list); 583 INIT_LIST_HEAD(&m->unsent_req_list); 584 INIT_WORK(&m->rq, p9_read_work); 585 INIT_WORK(&m->wq, p9_write_work); 586 INIT_LIST_HEAD(&m->poll_pending_link); 587 init_poll_funcptr(&m->pt, p9_pollwait); 588 589 n = p9_fd_poll(client, &m->pt); 590 if (n & POLLIN) { 591 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p can read\n", m); 592 set_bit(Rpending, &m->wsched); 593 } 594 595 if (n & POLLOUT) { 596 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p can write\n", m); 597 set_bit(Wpending, &m->wsched); 598 } 599 600 return m; 601 } 602 603 /** 604 * p9_poll_mux - polls a mux and schedules read or write works if necessary 605 * @m: connection to poll 606 * 607 */ 608 609 static void p9_poll_mux(struct p9_conn *m) 610 { 611 int n; 612 613 if (m->err < 0) 614 return; 615 616 n = p9_fd_poll(m->client, NULL); 617 if (n < 0 || n & (POLLERR | POLLHUP | POLLNVAL)) { 618 P9_DPRINTK(P9_DEBUG_TRANS, "error mux %p err %d\n", m, n); 619 if (n >= 0) 620 n = -ECONNRESET; 621 p9_conn_cancel(m, n); 622 } 623 624 if (n & POLLIN) { 625 set_bit(Rpending, &m->wsched); 626 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p can read\n", m); 627 if (!test_and_set_bit(Rworksched, &m->wsched)) { 628 P9_DPRINTK(P9_DEBUG_TRANS, "sched read work %p\n", m); 629 queue_work(p9_mux_wq, &m->rq); 630 } 631 } 632 633 if (n & POLLOUT) { 634 set_bit(Wpending, &m->wsched); 635 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p can write\n", m); 636 if ((m->wsize || !list_empty(&m->unsent_req_list)) 637 && !test_and_set_bit(Wworksched, &m->wsched)) { 638 P9_DPRINTK(P9_DEBUG_TRANS, "sched write work %p\n", m); 639 queue_work(p9_mux_wq, &m->wq); 640 } 641 } 642 } 643 644 /** 645 * p9_fd_request - send 9P request 646 * The function can sleep until the request is scheduled for sending. 647 * The function can be interrupted. Return from the function is not 648 * a guarantee that the request is sent successfully. 649 * 650 * @client: client instance 651 * @req: request to be sent 652 * 653 */ 654 655 static int p9_fd_request(struct p9_client *client, struct p9_req_t *req) 656 { 657 int n; 658 struct p9_trans_fd *ts = client->trans; 659 struct p9_conn *m = ts->conn; 660 661 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p task %p tcall %p id %d\n", m, 662 current, req->tc, req->tc->id); 663 if (m->err < 0) 664 return m->err; 665 666 spin_lock(&client->lock); 667 req->status = REQ_STATUS_UNSENT; 668 list_add_tail(&req->req_list, &m->unsent_req_list); 669 spin_unlock(&client->lock); 670 671 if (test_and_clear_bit(Wpending, &m->wsched)) 672 n = POLLOUT; 673 else 674 n = p9_fd_poll(m->client, NULL); 675 676 if (n & POLLOUT && !test_and_set_bit(Wworksched, &m->wsched)) 677 queue_work(p9_mux_wq, &m->wq); 678 679 return 0; 680 } 681 682 static int p9_fd_cancel(struct p9_client *client, struct p9_req_t *req) 683 { 684 int ret = 1; 685 686 P9_DPRINTK(P9_DEBUG_TRANS, "client %p req %p\n", client, req); 687 688 spin_lock(&client->lock); 689 690 if (req->status == REQ_STATUS_UNSENT) { 691 list_del(&req->req_list); 692 req->status = REQ_STATUS_FLSHD; 693 ret = 0; 694 } else if (req->status == REQ_STATUS_SENT) 695 req->status = REQ_STATUS_FLSH; 696 697 spin_unlock(&client->lock); 698 699 return ret; 700 } 701 702 /** 703 * parse_opts - parse mount options into p9_fd_opts structure 704 * @params: options string passed from mount 705 * @opts: fd transport-specific structure to parse options into 706 * 707 * Returns 0 upon success, -ERRNO upon failure 708 */ 709 710 static int parse_opts(char *params, struct p9_fd_opts *opts) 711 { 712 char *p; 713 substring_t args[MAX_OPT_ARGS]; 714 int option; 715 char *options; 716 int ret; 717 718 opts->port = P9_PORT; 719 opts->rfd = ~0; 720 opts->wfd = ~0; 721 722 if (!params) 723 return 0; 724 725 options = kstrdup(params, GFP_KERNEL); 726 if (!options) { 727 P9_DPRINTK(P9_DEBUG_ERROR, 728 "failed to allocate copy of option string\n"); 729 return -ENOMEM; 730 } 731 732 while ((p = strsep(&options, ",")) != NULL) { 733 int token; 734 int r; 735 if (!*p) 736 continue; 737 token = match_token(p, tokens, args); 738 if (token != Opt_err) { 739 r = match_int(&args[0], &option); 740 if (r < 0) { 741 P9_DPRINTK(P9_DEBUG_ERROR, 742 "integer field, but no integer?\n"); 743 ret = r; 744 continue; 745 } 746 } 747 switch (token) { 748 case Opt_port: 749 opts->port = option; 750 break; 751 case Opt_rfdno: 752 opts->rfd = option; 753 break; 754 case Opt_wfdno: 755 opts->wfd = option; 756 break; 757 default: 758 continue; 759 } 760 } 761 kfree(options); 762 return 0; 763 } 764 765 static int p9_fd_open(struct p9_client *client, int rfd, int wfd) 766 { 767 struct p9_trans_fd *ts = kmalloc(sizeof(struct p9_trans_fd), 768 GFP_KERNEL); 769 if (!ts) 770 return -ENOMEM; 771 772 ts->rd = fget(rfd); 773 ts->wr = fget(wfd); 774 if (!ts->rd || !ts->wr) { 775 if (ts->rd) 776 fput(ts->rd); 777 if (ts->wr) 778 fput(ts->wr); 779 kfree(ts); 780 return -EIO; 781 } 782 783 client->trans = ts; 784 client->status = Connected; 785 786 return 0; 787 } 788 789 static int p9_socket_open(struct p9_client *client, struct socket *csocket) 790 { 791 int fd, ret; 792 793 csocket->sk->sk_allocation = GFP_NOIO; 794 fd = sock_map_fd(csocket, 0); 795 if (fd < 0) { 796 P9_EPRINTK(KERN_ERR, "p9_socket_open: failed to map fd\n"); 797 return fd; 798 } 799 800 ret = p9_fd_open(client, fd, fd); 801 if (ret < 0) { 802 P9_EPRINTK(KERN_ERR, "p9_socket_open: failed to open fd\n"); 803 sockfd_put(csocket); 804 return ret; 805 } 806 807 ((struct p9_trans_fd *)client->trans)->rd->f_flags |= O_NONBLOCK; 808 809 return 0; 810 } 811 812 /** 813 * p9_mux_destroy - cancels all pending requests and frees mux resources 814 * @m: mux to destroy 815 * 816 */ 817 818 static void p9_conn_destroy(struct p9_conn *m) 819 { 820 P9_DPRINTK(P9_DEBUG_TRANS, "mux %p prev %p next %p\n", m, 821 m->mux_list.prev, m->mux_list.next); 822 823 p9_mux_poll_stop(m); 824 cancel_work_sync(&m->rq); 825 cancel_work_sync(&m->wq); 826 827 p9_conn_cancel(m, -ECONNRESET); 828 829 m->client = NULL; 830 kfree(m); 831 } 832 833 /** 834 * p9_fd_close - shutdown file descriptor transport 835 * @client: client instance 836 * 837 */ 838 839 static void p9_fd_close(struct p9_client *client) 840 { 841 struct p9_trans_fd *ts; 842 843 if (!client) 844 return; 845 846 ts = client->trans; 847 if (!ts) 848 return; 849 850 client->status = Disconnected; 851 852 p9_conn_destroy(ts->conn); 853 854 if (ts->rd) 855 fput(ts->rd); 856 if (ts->wr) 857 fput(ts->wr); 858 859 kfree(ts); 860 } 861 862 /* 863 * stolen from NFS - maybe should be made a generic function? 864 */ 865 static inline int valid_ipaddr4(const char *buf) 866 { 867 int rc, count, in[4]; 868 869 rc = sscanf(buf, "%d.%d.%d.%d", &in[0], &in[1], &in[2], &in[3]); 870 if (rc != 4) 871 return -EINVAL; 872 for (count = 0; count < 4; count++) { 873 if (in[count] > 255) 874 return -EINVAL; 875 } 876 return 0; 877 } 878 879 static int 880 p9_fd_create_tcp(struct p9_client *client, const char *addr, char *args) 881 { 882 int err; 883 struct socket *csocket; 884 struct sockaddr_in sin_server; 885 struct p9_fd_opts opts; 886 struct p9_trans_fd *p = NULL; /* this gets allocated in p9_fd_open */ 887 888 err = parse_opts(args, &opts); 889 if (err < 0) 890 return err; 891 892 if (valid_ipaddr4(addr) < 0) 893 return -EINVAL; 894 895 csocket = NULL; 896 897 sin_server.sin_family = AF_INET; 898 sin_server.sin_addr.s_addr = in_aton(addr); 899 sin_server.sin_port = htons(opts.port); 900 sock_create_kern(PF_INET, SOCK_STREAM, IPPROTO_TCP, &csocket); 901 902 if (!csocket) { 903 P9_EPRINTK(KERN_ERR, "p9_trans_tcp: problem creating socket\n"); 904 err = -EIO; 905 goto error; 906 } 907 908 err = csocket->ops->connect(csocket, 909 (struct sockaddr *)&sin_server, 910 sizeof(struct sockaddr_in), 0); 911 if (err < 0) { 912 P9_EPRINTK(KERN_ERR, 913 "p9_trans_tcp: problem connecting socket to %s\n", 914 addr); 915 goto error; 916 } 917 918 err = p9_socket_open(client, csocket); 919 if (err < 0) 920 goto error; 921 922 p = (struct p9_trans_fd *) client->trans; 923 p->conn = p9_conn_create(client); 924 if (IS_ERR(p->conn)) { 925 err = PTR_ERR(p->conn); 926 p->conn = NULL; 927 goto error; 928 } 929 930 return 0; 931 932 error: 933 if (csocket) 934 sock_release(csocket); 935 936 kfree(p); 937 938 return err; 939 } 940 941 static int 942 p9_fd_create_unix(struct p9_client *client, const char *addr, char *args) 943 { 944 int err; 945 struct socket *csocket; 946 struct sockaddr_un sun_server; 947 struct p9_trans_fd *p = NULL; /* this gets allocated in p9_fd_open */ 948 949 csocket = NULL; 950 951 if (strlen(addr) > UNIX_PATH_MAX) { 952 P9_EPRINTK(KERN_ERR, "p9_trans_unix: address too long: %s\n", 953 addr); 954 err = -ENAMETOOLONG; 955 goto error; 956 } 957 958 sun_server.sun_family = PF_UNIX; 959 strcpy(sun_server.sun_path, addr); 960 sock_create_kern(PF_UNIX, SOCK_STREAM, 0, &csocket); 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 goto error; 968 } 969 970 err = p9_socket_open(client, csocket); 971 if (err < 0) 972 goto error; 973 974 p = (struct p9_trans_fd *) client->trans; 975 p->conn = p9_conn_create(client); 976 if (IS_ERR(p->conn)) { 977 err = PTR_ERR(p->conn); 978 p->conn = NULL; 979 goto error; 980 } 981 982 return 0; 983 984 error: 985 if (csocket) 986 sock_release(csocket); 987 988 kfree(p); 989 return err; 990 } 991 992 static int 993 p9_fd_create(struct p9_client *client, const char *addr, char *args) 994 { 995 int err; 996 struct p9_fd_opts opts; 997 struct p9_trans_fd *p = NULL; /* this get allocated in p9_fd_open */ 998 999 parse_opts(args, &opts); 1000 1001 if (opts.rfd == ~0 || opts.wfd == ~0) { 1002 printk(KERN_ERR "v9fs: Insufficient options for proto=fd\n"); 1003 return -ENOPROTOOPT; 1004 } 1005 1006 err = p9_fd_open(client, opts.rfd, opts.wfd); 1007 if (err < 0) 1008 goto error; 1009 1010 p = (struct p9_trans_fd *) client->trans; 1011 p->conn = p9_conn_create(client); 1012 if (IS_ERR(p->conn)) { 1013 err = PTR_ERR(p->conn); 1014 p->conn = NULL; 1015 goto error; 1016 } 1017 1018 return 0; 1019 1020 error: 1021 kfree(p); 1022 return err; 1023 } 1024 1025 static struct p9_trans_module p9_tcp_trans = { 1026 .name = "tcp", 1027 .maxsize = MAX_SOCK_BUF, 1028 .def = 1, 1029 .create = p9_fd_create_tcp, 1030 .close = p9_fd_close, 1031 .request = p9_fd_request, 1032 .cancel = p9_fd_cancel, 1033 .owner = THIS_MODULE, 1034 }; 1035 1036 static struct p9_trans_module p9_unix_trans = { 1037 .name = "unix", 1038 .maxsize = MAX_SOCK_BUF, 1039 .def = 0, 1040 .create = p9_fd_create_unix, 1041 .close = p9_fd_close, 1042 .request = p9_fd_request, 1043 .cancel = p9_fd_cancel, 1044 .owner = THIS_MODULE, 1045 }; 1046 1047 static struct p9_trans_module p9_fd_trans = { 1048 .name = "fd", 1049 .maxsize = MAX_SOCK_BUF, 1050 .def = 0, 1051 .create = p9_fd_create, 1052 .close = p9_fd_close, 1053 .request = p9_fd_request, 1054 .cancel = p9_fd_cancel, 1055 .owner = THIS_MODULE, 1056 }; 1057 1058 /** 1059 * p9_poll_proc - poll worker thread 1060 * @a: thread state and arguments 1061 * 1062 * polls all v9fs transports for new events and queues the appropriate 1063 * work to the work queue 1064 * 1065 */ 1066 1067 static int p9_poll_proc(void *a) 1068 { 1069 unsigned long flags; 1070 1071 P9_DPRINTK(P9_DEBUG_TRANS, "start %p\n", current); 1072 repeat: 1073 spin_lock_irqsave(&p9_poll_lock, flags); 1074 while (!list_empty(&p9_poll_pending_list)) { 1075 struct p9_conn *conn = list_first_entry(&p9_poll_pending_list, 1076 struct p9_conn, 1077 poll_pending_link); 1078 list_del_init(&conn->poll_pending_link); 1079 spin_unlock_irqrestore(&p9_poll_lock, flags); 1080 1081 p9_poll_mux(conn); 1082 1083 spin_lock_irqsave(&p9_poll_lock, flags); 1084 } 1085 spin_unlock_irqrestore(&p9_poll_lock, flags); 1086 1087 set_current_state(TASK_INTERRUPTIBLE); 1088 if (list_empty(&p9_poll_pending_list)) { 1089 P9_DPRINTK(P9_DEBUG_TRANS, "sleeping...\n"); 1090 schedule(); 1091 } 1092 __set_current_state(TASK_RUNNING); 1093 1094 if (!kthread_should_stop()) 1095 goto repeat; 1096 1097 P9_DPRINTK(P9_DEBUG_TRANS, "finish\n"); 1098 return 0; 1099 } 1100 1101 int p9_trans_fd_init(void) 1102 { 1103 p9_mux_wq = create_workqueue("v9fs"); 1104 if (!p9_mux_wq) { 1105 printk(KERN_WARNING "v9fs: mux: creating workqueue failed\n"); 1106 return -ENOMEM; 1107 } 1108 1109 p9_poll_task = kthread_run(p9_poll_proc, NULL, "v9fs-poll"); 1110 if (IS_ERR(p9_poll_task)) { 1111 destroy_workqueue(p9_mux_wq); 1112 printk(KERN_WARNING "v9fs: mux: creating poll task failed\n"); 1113 return PTR_ERR(p9_poll_task); 1114 } 1115 1116 v9fs_register_trans(&p9_tcp_trans); 1117 v9fs_register_trans(&p9_unix_trans); 1118 v9fs_register_trans(&p9_fd_trans); 1119 1120 return 0; 1121 } 1122 1123 void p9_trans_fd_exit(void) 1124 { 1125 kthread_stop(p9_poll_task); 1126 v9fs_unregister_trans(&p9_tcp_trans); 1127 v9fs_unregister_trans(&p9_unix_trans); 1128 v9fs_unregister_trans(&p9_fd_trans); 1129 1130 destroy_workqueue(p9_mux_wq); 1131 } 1132