1 /* 2 * linux/net/sunrpc/xprtsock.c 3 * 4 * Client-side transport implementation for sockets. 5 * 6 * TCP callback races fixes (C) 1998 Red Hat 7 * TCP send fixes (C) 1998 Red Hat 8 * TCP NFS related read + write fixes 9 * (C) 1999 Dave Airlie, University of Limerick, Ireland <airlied@linux.ie> 10 * 11 * Rewrite of larges part of the code in order to stabilize TCP stuff. 12 * Fix behaviour when socket buffer is full. 13 * (C) 1999 Trond Myklebust <trond.myklebust@fys.uio.no> 14 * 15 * IP socket transport implementation, (C) 2005 Chuck Lever <cel@netapp.com> 16 * 17 * IPv6 support contributed by Gilles Quillard, Bull Open Source, 2005. 18 * <gilles.quillard@bull.net> 19 */ 20 21 #include <linux/types.h> 22 #include <linux/string.h> 23 #include <linux/slab.h> 24 #include <linux/module.h> 25 #include <linux/capability.h> 26 #include <linux/pagemap.h> 27 #include <linux/errno.h> 28 #include <linux/socket.h> 29 #include <linux/in.h> 30 #include <linux/net.h> 31 #include <linux/mm.h> 32 #include <linux/un.h> 33 #include <linux/udp.h> 34 #include <linux/tcp.h> 35 #include <linux/sunrpc/clnt.h> 36 #include <linux/sunrpc/addr.h> 37 #include <linux/sunrpc/sched.h> 38 #include <linux/sunrpc/svcsock.h> 39 #include <linux/sunrpc/xprtsock.h> 40 #include <linux/file.h> 41 #ifdef CONFIG_SUNRPC_BACKCHANNEL 42 #include <linux/sunrpc/bc_xprt.h> 43 #endif 44 45 #include <net/sock.h> 46 #include <net/checksum.h> 47 #include <net/udp.h> 48 #include <net/tcp.h> 49 50 #include <trace/events/sunrpc.h> 51 52 #include "sunrpc.h" 53 54 static void xs_close(struct rpc_xprt *xprt); 55 56 /* 57 * xprtsock tunables 58 */ 59 static unsigned int xprt_udp_slot_table_entries = RPC_DEF_SLOT_TABLE; 60 static unsigned int xprt_tcp_slot_table_entries = RPC_MIN_SLOT_TABLE; 61 static unsigned int xprt_max_tcp_slot_table_entries = RPC_MAX_SLOT_TABLE; 62 63 static unsigned int xprt_min_resvport = RPC_DEF_MIN_RESVPORT; 64 static unsigned int xprt_max_resvport = RPC_DEF_MAX_RESVPORT; 65 66 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 67 68 #define XS_TCP_LINGER_TO (15U * HZ) 69 static unsigned int xs_tcp_fin_timeout __read_mostly = XS_TCP_LINGER_TO; 70 71 /* 72 * We can register our own files under /proc/sys/sunrpc by 73 * calling register_sysctl_table() again. The files in that 74 * directory become the union of all files registered there. 75 * 76 * We simply need to make sure that we don't collide with 77 * someone else's file names! 78 */ 79 80 static unsigned int min_slot_table_size = RPC_MIN_SLOT_TABLE; 81 static unsigned int max_slot_table_size = RPC_MAX_SLOT_TABLE; 82 static unsigned int max_tcp_slot_table_limit = RPC_MAX_SLOT_TABLE_LIMIT; 83 static unsigned int xprt_min_resvport_limit = RPC_MIN_RESVPORT; 84 static unsigned int xprt_max_resvport_limit = RPC_MAX_RESVPORT; 85 86 static struct ctl_table_header *sunrpc_table_header; 87 88 /* 89 * FIXME: changing the UDP slot table size should also resize the UDP 90 * socket buffers for existing UDP transports 91 */ 92 static struct ctl_table xs_tunables_table[] = { 93 { 94 .procname = "udp_slot_table_entries", 95 .data = &xprt_udp_slot_table_entries, 96 .maxlen = sizeof(unsigned int), 97 .mode = 0644, 98 .proc_handler = proc_dointvec_minmax, 99 .extra1 = &min_slot_table_size, 100 .extra2 = &max_slot_table_size 101 }, 102 { 103 .procname = "tcp_slot_table_entries", 104 .data = &xprt_tcp_slot_table_entries, 105 .maxlen = sizeof(unsigned int), 106 .mode = 0644, 107 .proc_handler = proc_dointvec_minmax, 108 .extra1 = &min_slot_table_size, 109 .extra2 = &max_slot_table_size 110 }, 111 { 112 .procname = "tcp_max_slot_table_entries", 113 .data = &xprt_max_tcp_slot_table_entries, 114 .maxlen = sizeof(unsigned int), 115 .mode = 0644, 116 .proc_handler = proc_dointvec_minmax, 117 .extra1 = &min_slot_table_size, 118 .extra2 = &max_tcp_slot_table_limit 119 }, 120 { 121 .procname = "min_resvport", 122 .data = &xprt_min_resvport, 123 .maxlen = sizeof(unsigned int), 124 .mode = 0644, 125 .proc_handler = proc_dointvec_minmax, 126 .extra1 = &xprt_min_resvport_limit, 127 .extra2 = &xprt_max_resvport_limit 128 }, 129 { 130 .procname = "max_resvport", 131 .data = &xprt_max_resvport, 132 .maxlen = sizeof(unsigned int), 133 .mode = 0644, 134 .proc_handler = proc_dointvec_minmax, 135 .extra1 = &xprt_min_resvport_limit, 136 .extra2 = &xprt_max_resvport_limit 137 }, 138 { 139 .procname = "tcp_fin_timeout", 140 .data = &xs_tcp_fin_timeout, 141 .maxlen = sizeof(xs_tcp_fin_timeout), 142 .mode = 0644, 143 .proc_handler = proc_dointvec_jiffies, 144 }, 145 { }, 146 }; 147 148 static struct ctl_table sunrpc_table[] = { 149 { 150 .procname = "sunrpc", 151 .mode = 0555, 152 .child = xs_tunables_table 153 }, 154 { }, 155 }; 156 157 #endif 158 159 /* 160 * Wait duration for a reply from the RPC portmapper. 161 */ 162 #define XS_BIND_TO (60U * HZ) 163 164 /* 165 * Delay if a UDP socket connect error occurs. This is most likely some 166 * kind of resource problem on the local host. 167 */ 168 #define XS_UDP_REEST_TO (2U * HZ) 169 170 /* 171 * The reestablish timeout allows clients to delay for a bit before attempting 172 * to reconnect to a server that just dropped our connection. 173 * 174 * We implement an exponential backoff when trying to reestablish a TCP 175 * transport connection with the server. Some servers like to drop a TCP 176 * connection when they are overworked, so we start with a short timeout and 177 * increase over time if the server is down or not responding. 178 */ 179 #define XS_TCP_INIT_REEST_TO (3U * HZ) 180 #define XS_TCP_MAX_REEST_TO (5U * 60 * HZ) 181 182 /* 183 * TCP idle timeout; client drops the transport socket if it is idle 184 * for this long. Note that we also timeout UDP sockets to prevent 185 * holding port numbers when there is no RPC traffic. 186 */ 187 #define XS_IDLE_DISC_TO (5U * 60 * HZ) 188 189 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 190 # undef RPC_DEBUG_DATA 191 # define RPCDBG_FACILITY RPCDBG_TRANS 192 #endif 193 194 #ifdef RPC_DEBUG_DATA 195 static void xs_pktdump(char *msg, u32 *packet, unsigned int count) 196 { 197 u8 *buf = (u8 *) packet; 198 int j; 199 200 dprintk("RPC: %s\n", msg); 201 for (j = 0; j < count && j < 128; j += 4) { 202 if (!(j & 31)) { 203 if (j) 204 dprintk("\n"); 205 dprintk("0x%04x ", j); 206 } 207 dprintk("%02x%02x%02x%02x ", 208 buf[j], buf[j+1], buf[j+2], buf[j+3]); 209 } 210 dprintk("\n"); 211 } 212 #else 213 static inline void xs_pktdump(char *msg, u32 *packet, unsigned int count) 214 { 215 /* NOP */ 216 } 217 #endif 218 219 static inline struct rpc_xprt *xprt_from_sock(struct sock *sk) 220 { 221 return (struct rpc_xprt *) sk->sk_user_data; 222 } 223 224 static inline struct sockaddr *xs_addr(struct rpc_xprt *xprt) 225 { 226 return (struct sockaddr *) &xprt->addr; 227 } 228 229 static inline struct sockaddr_un *xs_addr_un(struct rpc_xprt *xprt) 230 { 231 return (struct sockaddr_un *) &xprt->addr; 232 } 233 234 static inline struct sockaddr_in *xs_addr_in(struct rpc_xprt *xprt) 235 { 236 return (struct sockaddr_in *) &xprt->addr; 237 } 238 239 static inline struct sockaddr_in6 *xs_addr_in6(struct rpc_xprt *xprt) 240 { 241 return (struct sockaddr_in6 *) &xprt->addr; 242 } 243 244 static void xs_format_common_peer_addresses(struct rpc_xprt *xprt) 245 { 246 struct sockaddr *sap = xs_addr(xprt); 247 struct sockaddr_in6 *sin6; 248 struct sockaddr_in *sin; 249 struct sockaddr_un *sun; 250 char buf[128]; 251 252 switch (sap->sa_family) { 253 case AF_LOCAL: 254 sun = xs_addr_un(xprt); 255 strlcpy(buf, sun->sun_path, sizeof(buf)); 256 xprt->address_strings[RPC_DISPLAY_ADDR] = 257 kstrdup(buf, GFP_KERNEL); 258 break; 259 case AF_INET: 260 (void)rpc_ntop(sap, buf, sizeof(buf)); 261 xprt->address_strings[RPC_DISPLAY_ADDR] = 262 kstrdup(buf, GFP_KERNEL); 263 sin = xs_addr_in(xprt); 264 snprintf(buf, sizeof(buf), "%08x", ntohl(sin->sin_addr.s_addr)); 265 break; 266 case AF_INET6: 267 (void)rpc_ntop(sap, buf, sizeof(buf)); 268 xprt->address_strings[RPC_DISPLAY_ADDR] = 269 kstrdup(buf, GFP_KERNEL); 270 sin6 = xs_addr_in6(xprt); 271 snprintf(buf, sizeof(buf), "%pi6", &sin6->sin6_addr); 272 break; 273 default: 274 BUG(); 275 } 276 277 xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = kstrdup(buf, GFP_KERNEL); 278 } 279 280 static void xs_format_common_peer_ports(struct rpc_xprt *xprt) 281 { 282 struct sockaddr *sap = xs_addr(xprt); 283 char buf[128]; 284 285 snprintf(buf, sizeof(buf), "%u", rpc_get_port(sap)); 286 xprt->address_strings[RPC_DISPLAY_PORT] = kstrdup(buf, GFP_KERNEL); 287 288 snprintf(buf, sizeof(buf), "%4hx", rpc_get_port(sap)); 289 xprt->address_strings[RPC_DISPLAY_HEX_PORT] = kstrdup(buf, GFP_KERNEL); 290 } 291 292 static void xs_format_peer_addresses(struct rpc_xprt *xprt, 293 const char *protocol, 294 const char *netid) 295 { 296 xprt->address_strings[RPC_DISPLAY_PROTO] = protocol; 297 xprt->address_strings[RPC_DISPLAY_NETID] = netid; 298 xs_format_common_peer_addresses(xprt); 299 xs_format_common_peer_ports(xprt); 300 } 301 302 static void xs_update_peer_port(struct rpc_xprt *xprt) 303 { 304 kfree(xprt->address_strings[RPC_DISPLAY_HEX_PORT]); 305 kfree(xprt->address_strings[RPC_DISPLAY_PORT]); 306 307 xs_format_common_peer_ports(xprt); 308 } 309 310 static void xs_free_peer_addresses(struct rpc_xprt *xprt) 311 { 312 unsigned int i; 313 314 for (i = 0; i < RPC_DISPLAY_MAX; i++) 315 switch (i) { 316 case RPC_DISPLAY_PROTO: 317 case RPC_DISPLAY_NETID: 318 continue; 319 default: 320 kfree(xprt->address_strings[i]); 321 } 322 } 323 324 #define XS_SENDMSG_FLAGS (MSG_DONTWAIT | MSG_NOSIGNAL) 325 326 static int xs_send_kvec(struct socket *sock, struct sockaddr *addr, int addrlen, struct kvec *vec, unsigned int base, int more) 327 { 328 struct msghdr msg = { 329 .msg_name = addr, 330 .msg_namelen = addrlen, 331 .msg_flags = XS_SENDMSG_FLAGS | (more ? MSG_MORE : 0), 332 }; 333 struct kvec iov = { 334 .iov_base = vec->iov_base + base, 335 .iov_len = vec->iov_len - base, 336 }; 337 338 if (iov.iov_len != 0) 339 return kernel_sendmsg(sock, &msg, &iov, 1, iov.iov_len); 340 return kernel_sendmsg(sock, &msg, NULL, 0, 0); 341 } 342 343 static int xs_send_pagedata(struct socket *sock, struct xdr_buf *xdr, unsigned int base, int more, bool zerocopy, int *sent_p) 344 { 345 ssize_t (*do_sendpage)(struct socket *sock, struct page *page, 346 int offset, size_t size, int flags); 347 struct page **ppage; 348 unsigned int remainder; 349 int err; 350 351 remainder = xdr->page_len - base; 352 base += xdr->page_base; 353 ppage = xdr->pages + (base >> PAGE_SHIFT); 354 base &= ~PAGE_MASK; 355 do_sendpage = sock->ops->sendpage; 356 if (!zerocopy) 357 do_sendpage = sock_no_sendpage; 358 for(;;) { 359 unsigned int len = min_t(unsigned int, PAGE_SIZE - base, remainder); 360 int flags = XS_SENDMSG_FLAGS; 361 362 remainder -= len; 363 if (remainder != 0 || more) 364 flags |= MSG_MORE; 365 err = do_sendpage(sock, *ppage, base, len, flags); 366 if (remainder == 0 || err != len) 367 break; 368 *sent_p += err; 369 ppage++; 370 base = 0; 371 } 372 if (err > 0) { 373 *sent_p += err; 374 err = 0; 375 } 376 return err; 377 } 378 379 /** 380 * xs_sendpages - write pages directly to a socket 381 * @sock: socket to send on 382 * @addr: UDP only -- address of destination 383 * @addrlen: UDP only -- length of destination address 384 * @xdr: buffer containing this request 385 * @base: starting position in the buffer 386 * @zerocopy: true if it is safe to use sendpage() 387 * @sent_p: return the total number of bytes successfully queued for sending 388 * 389 */ 390 static int xs_sendpages(struct socket *sock, struct sockaddr *addr, int addrlen, struct xdr_buf *xdr, unsigned int base, bool zerocopy, int *sent_p) 391 { 392 unsigned int remainder = xdr->len - base; 393 int err = 0; 394 int sent = 0; 395 396 if (unlikely(!sock)) 397 return -ENOTSOCK; 398 399 clear_bit(SOCK_ASYNC_NOSPACE, &sock->flags); 400 if (base != 0) { 401 addr = NULL; 402 addrlen = 0; 403 } 404 405 if (base < xdr->head[0].iov_len || addr != NULL) { 406 unsigned int len = xdr->head[0].iov_len - base; 407 remainder -= len; 408 err = xs_send_kvec(sock, addr, addrlen, &xdr->head[0], base, remainder != 0); 409 if (remainder == 0 || err != len) 410 goto out; 411 *sent_p += err; 412 base = 0; 413 } else 414 base -= xdr->head[0].iov_len; 415 416 if (base < xdr->page_len) { 417 unsigned int len = xdr->page_len - base; 418 remainder -= len; 419 err = xs_send_pagedata(sock, xdr, base, remainder != 0, zerocopy, &sent); 420 *sent_p += sent; 421 if (remainder == 0 || sent != len) 422 goto out; 423 base = 0; 424 } else 425 base -= xdr->page_len; 426 427 if (base >= xdr->tail[0].iov_len) 428 return 0; 429 err = xs_send_kvec(sock, NULL, 0, &xdr->tail[0], base, 0); 430 out: 431 if (err > 0) { 432 *sent_p += err; 433 err = 0; 434 } 435 return err; 436 } 437 438 static void xs_nospace_callback(struct rpc_task *task) 439 { 440 struct sock_xprt *transport = container_of(task->tk_rqstp->rq_xprt, struct sock_xprt, xprt); 441 442 transport->inet->sk_write_pending--; 443 clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags); 444 } 445 446 /** 447 * xs_nospace - place task on wait queue if transmit was incomplete 448 * @task: task to put to sleep 449 * 450 */ 451 static int xs_nospace(struct rpc_task *task) 452 { 453 struct rpc_rqst *req = task->tk_rqstp; 454 struct rpc_xprt *xprt = req->rq_xprt; 455 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); 456 struct sock *sk = transport->inet; 457 int ret = -EAGAIN; 458 459 dprintk("RPC: %5u xmit incomplete (%u left of %u)\n", 460 task->tk_pid, req->rq_slen - req->rq_bytes_sent, 461 req->rq_slen); 462 463 /* Protect against races with write_space */ 464 spin_lock_bh(&xprt->transport_lock); 465 466 /* Don't race with disconnect */ 467 if (xprt_connected(xprt)) { 468 if (test_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags)) { 469 /* 470 * Notify TCP that we're limited by the application 471 * window size 472 */ 473 set_bit(SOCK_NOSPACE, &transport->sock->flags); 474 sk->sk_write_pending++; 475 /* ...and wait for more buffer space */ 476 xprt_wait_for_buffer_space(task, xs_nospace_callback); 477 } 478 } else { 479 clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags); 480 ret = -ENOTCONN; 481 } 482 483 spin_unlock_bh(&xprt->transport_lock); 484 485 /* Race breaker in case memory is freed before above code is called */ 486 sk->sk_write_space(sk); 487 return ret; 488 } 489 490 /* 491 * Construct a stream transport record marker in @buf. 492 */ 493 static inline void xs_encode_stream_record_marker(struct xdr_buf *buf) 494 { 495 u32 reclen = buf->len - sizeof(rpc_fraghdr); 496 rpc_fraghdr *base = buf->head[0].iov_base; 497 *base = cpu_to_be32(RPC_LAST_STREAM_FRAGMENT | reclen); 498 } 499 500 /** 501 * xs_local_send_request - write an RPC request to an AF_LOCAL socket 502 * @task: RPC task that manages the state of an RPC request 503 * 504 * Return values: 505 * 0: The request has been sent 506 * EAGAIN: The socket was blocked, please call again later to 507 * complete the request 508 * ENOTCONN: Caller needs to invoke connect logic then call again 509 * other: Some other error occured, the request was not sent 510 */ 511 static int xs_local_send_request(struct rpc_task *task) 512 { 513 struct rpc_rqst *req = task->tk_rqstp; 514 struct rpc_xprt *xprt = req->rq_xprt; 515 struct sock_xprt *transport = 516 container_of(xprt, struct sock_xprt, xprt); 517 struct xdr_buf *xdr = &req->rq_snd_buf; 518 int status; 519 int sent = 0; 520 521 xs_encode_stream_record_marker(&req->rq_snd_buf); 522 523 xs_pktdump("packet data:", 524 req->rq_svec->iov_base, req->rq_svec->iov_len); 525 526 status = xs_sendpages(transport->sock, NULL, 0, xdr, req->rq_bytes_sent, 527 true, &sent); 528 dprintk("RPC: %s(%u) = %d\n", 529 __func__, xdr->len - req->rq_bytes_sent, status); 530 531 if (status == -EAGAIN && sock_writeable(transport->inet)) 532 status = -ENOBUFS; 533 534 if (likely(sent > 0) || status == 0) { 535 req->rq_bytes_sent += sent; 536 req->rq_xmit_bytes_sent += sent; 537 if (likely(req->rq_bytes_sent >= req->rq_slen)) { 538 req->rq_bytes_sent = 0; 539 return 0; 540 } 541 status = -EAGAIN; 542 } 543 544 switch (status) { 545 case -ENOBUFS: 546 break; 547 case -EAGAIN: 548 status = xs_nospace(task); 549 break; 550 default: 551 dprintk("RPC: sendmsg returned unrecognized error %d\n", 552 -status); 553 case -EPIPE: 554 xs_close(xprt); 555 status = -ENOTCONN; 556 } 557 558 return status; 559 } 560 561 /** 562 * xs_udp_send_request - write an RPC request to a UDP socket 563 * @task: address of RPC task that manages the state of an RPC request 564 * 565 * Return values: 566 * 0: The request has been sent 567 * EAGAIN: The socket was blocked, please call again later to 568 * complete the request 569 * ENOTCONN: Caller needs to invoke connect logic then call again 570 * other: Some other error occurred, the request was not sent 571 */ 572 static int xs_udp_send_request(struct rpc_task *task) 573 { 574 struct rpc_rqst *req = task->tk_rqstp; 575 struct rpc_xprt *xprt = req->rq_xprt; 576 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); 577 struct xdr_buf *xdr = &req->rq_snd_buf; 578 int sent = 0; 579 int status; 580 581 xs_pktdump("packet data:", 582 req->rq_svec->iov_base, 583 req->rq_svec->iov_len); 584 585 if (!xprt_bound(xprt)) 586 return -ENOTCONN; 587 status = xs_sendpages(transport->sock, xs_addr(xprt), xprt->addrlen, 588 xdr, req->rq_bytes_sent, true, &sent); 589 590 dprintk("RPC: xs_udp_send_request(%u) = %d\n", 591 xdr->len - req->rq_bytes_sent, status); 592 593 /* firewall is blocking us, don't return -EAGAIN or we end up looping */ 594 if (status == -EPERM) 595 goto process_status; 596 597 if (status == -EAGAIN && sock_writeable(transport->inet)) 598 status = -ENOBUFS; 599 600 if (sent > 0 || status == 0) { 601 req->rq_xmit_bytes_sent += sent; 602 if (sent >= req->rq_slen) 603 return 0; 604 /* Still some bytes left; set up for a retry later. */ 605 status = -EAGAIN; 606 } 607 608 process_status: 609 switch (status) { 610 case -ENOTSOCK: 611 status = -ENOTCONN; 612 /* Should we call xs_close() here? */ 613 break; 614 case -EAGAIN: 615 status = xs_nospace(task); 616 break; 617 default: 618 dprintk("RPC: sendmsg returned unrecognized error %d\n", 619 -status); 620 case -ENETUNREACH: 621 case -ENOBUFS: 622 case -EPIPE: 623 case -ECONNREFUSED: 624 case -EPERM: 625 /* When the server has died, an ICMP port unreachable message 626 * prompts ECONNREFUSED. */ 627 clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags); 628 } 629 630 return status; 631 } 632 633 /** 634 * xs_tcp_send_request - write an RPC request to a TCP socket 635 * @task: address of RPC task that manages the state of an RPC request 636 * 637 * Return values: 638 * 0: The request has been sent 639 * EAGAIN: The socket was blocked, please call again later to 640 * complete the request 641 * ENOTCONN: Caller needs to invoke connect logic then call again 642 * other: Some other error occurred, the request was not sent 643 * 644 * XXX: In the case of soft timeouts, should we eventually give up 645 * if sendmsg is not able to make progress? 646 */ 647 static int xs_tcp_send_request(struct rpc_task *task) 648 { 649 struct rpc_rqst *req = task->tk_rqstp; 650 struct rpc_xprt *xprt = req->rq_xprt; 651 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); 652 struct xdr_buf *xdr = &req->rq_snd_buf; 653 bool zerocopy = true; 654 int status; 655 int sent; 656 657 xs_encode_stream_record_marker(&req->rq_snd_buf); 658 659 xs_pktdump("packet data:", 660 req->rq_svec->iov_base, 661 req->rq_svec->iov_len); 662 /* Don't use zero copy if this is a resend. If the RPC call 663 * completes while the socket holds a reference to the pages, 664 * then we may end up resending corrupted data. 665 */ 666 if (task->tk_flags & RPC_TASK_SENT) 667 zerocopy = false; 668 669 /* Continue transmitting the packet/record. We must be careful 670 * to cope with writespace callbacks arriving _after_ we have 671 * called sendmsg(). */ 672 while (1) { 673 sent = 0; 674 status = xs_sendpages(transport->sock, NULL, 0, xdr, 675 req->rq_bytes_sent, zerocopy, &sent); 676 677 dprintk("RPC: xs_tcp_send_request(%u) = %d\n", 678 xdr->len - req->rq_bytes_sent, status); 679 680 /* If we've sent the entire packet, immediately 681 * reset the count of bytes sent. */ 682 req->rq_bytes_sent += sent; 683 req->rq_xmit_bytes_sent += sent; 684 if (likely(req->rq_bytes_sent >= req->rq_slen)) { 685 req->rq_bytes_sent = 0; 686 return 0; 687 } 688 689 if (status < 0) 690 break; 691 if (sent == 0) { 692 status = -EAGAIN; 693 break; 694 } 695 } 696 if (status == -EAGAIN && sk_stream_is_writeable(transport->inet)) 697 status = -ENOBUFS; 698 699 switch (status) { 700 case -ENOTSOCK: 701 status = -ENOTCONN; 702 /* Should we call xs_close() here? */ 703 break; 704 case -EAGAIN: 705 status = xs_nospace(task); 706 break; 707 default: 708 dprintk("RPC: sendmsg returned unrecognized error %d\n", 709 -status); 710 case -ECONNRESET: 711 case -ECONNREFUSED: 712 case -ENOTCONN: 713 case -EADDRINUSE: 714 case -ENOBUFS: 715 case -EPIPE: 716 clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags); 717 } 718 719 return status; 720 } 721 722 /** 723 * xs_tcp_release_xprt - clean up after a tcp transmission 724 * @xprt: transport 725 * @task: rpc task 726 * 727 * This cleans up if an error causes us to abort the transmission of a request. 728 * In this case, the socket may need to be reset in order to avoid confusing 729 * the server. 730 */ 731 static void xs_tcp_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task) 732 { 733 struct rpc_rqst *req; 734 735 if (task != xprt->snd_task) 736 return; 737 if (task == NULL) 738 goto out_release; 739 req = task->tk_rqstp; 740 if (req == NULL) 741 goto out_release; 742 if (req->rq_bytes_sent == 0) 743 goto out_release; 744 if (req->rq_bytes_sent == req->rq_snd_buf.len) 745 goto out_release; 746 set_bit(XPRT_CLOSE_WAIT, &xprt->state); 747 out_release: 748 xprt_release_xprt(xprt, task); 749 } 750 751 static void xs_save_old_callbacks(struct sock_xprt *transport, struct sock *sk) 752 { 753 transport->old_data_ready = sk->sk_data_ready; 754 transport->old_state_change = sk->sk_state_change; 755 transport->old_write_space = sk->sk_write_space; 756 transport->old_error_report = sk->sk_error_report; 757 } 758 759 static void xs_restore_old_callbacks(struct sock_xprt *transport, struct sock *sk) 760 { 761 sk->sk_data_ready = transport->old_data_ready; 762 sk->sk_state_change = transport->old_state_change; 763 sk->sk_write_space = transport->old_write_space; 764 sk->sk_error_report = transport->old_error_report; 765 } 766 767 static void xs_sock_reset_connection_flags(struct rpc_xprt *xprt) 768 { 769 smp_mb__before_atomic(); 770 clear_bit(XPRT_CLOSE_WAIT, &xprt->state); 771 clear_bit(XPRT_CLOSING, &xprt->state); 772 smp_mb__after_atomic(); 773 } 774 775 static void xs_sock_mark_closed(struct rpc_xprt *xprt) 776 { 777 xs_sock_reset_connection_flags(xprt); 778 /* Mark transport as closed and wake up all pending tasks */ 779 xprt_disconnect_done(xprt); 780 } 781 782 /** 783 * xs_error_report - callback to handle TCP socket state errors 784 * @sk: socket 785 * 786 * Note: we don't call sock_error() since there may be a rpc_task 787 * using the socket, and so we don't want to clear sk->sk_err. 788 */ 789 static void xs_error_report(struct sock *sk) 790 { 791 struct rpc_xprt *xprt; 792 int err; 793 794 read_lock_bh(&sk->sk_callback_lock); 795 if (!(xprt = xprt_from_sock(sk))) 796 goto out; 797 798 err = -sk->sk_err; 799 if (err == 0) 800 goto out; 801 /* Is this a reset event? */ 802 if (sk->sk_state == TCP_CLOSE) 803 xs_sock_mark_closed(xprt); 804 dprintk("RPC: xs_error_report client %p, error=%d...\n", 805 xprt, -err); 806 trace_rpc_socket_error(xprt, sk->sk_socket, err); 807 xprt_wake_pending_tasks(xprt, err); 808 out: 809 read_unlock_bh(&sk->sk_callback_lock); 810 } 811 812 static void xs_reset_transport(struct sock_xprt *transport) 813 { 814 struct socket *sock = transport->sock; 815 struct sock *sk = transport->inet; 816 struct rpc_xprt *xprt = &transport->xprt; 817 818 if (sk == NULL) 819 return; 820 821 if (atomic_read(&transport->xprt.swapper)) 822 sk_clear_memalloc(sk); 823 824 kernel_sock_shutdown(sock, SHUT_RDWR); 825 826 write_lock_bh(&sk->sk_callback_lock); 827 transport->inet = NULL; 828 transport->sock = NULL; 829 830 sk->sk_user_data = NULL; 831 832 xs_restore_old_callbacks(transport, sk); 833 xprt_clear_connected(xprt); 834 write_unlock_bh(&sk->sk_callback_lock); 835 xs_sock_reset_connection_flags(xprt); 836 837 trace_rpc_socket_close(xprt, sock); 838 sock_release(sock); 839 } 840 841 /** 842 * xs_close - close a socket 843 * @xprt: transport 844 * 845 * This is used when all requests are complete; ie, no DRC state remains 846 * on the server we want to save. 847 * 848 * The caller _must_ be holding XPRT_LOCKED in order to avoid issues with 849 * xs_reset_transport() zeroing the socket from underneath a writer. 850 */ 851 static void xs_close(struct rpc_xprt *xprt) 852 { 853 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); 854 855 dprintk("RPC: xs_close xprt %p\n", xprt); 856 857 xs_reset_transport(transport); 858 xprt->reestablish_timeout = 0; 859 860 xprt_disconnect_done(xprt); 861 } 862 863 static void xs_inject_disconnect(struct rpc_xprt *xprt) 864 { 865 dprintk("RPC: injecting transport disconnect on xprt=%p\n", 866 xprt); 867 xprt_disconnect_done(xprt); 868 } 869 870 static void xs_xprt_free(struct rpc_xprt *xprt) 871 { 872 xs_free_peer_addresses(xprt); 873 xprt_free(xprt); 874 } 875 876 /** 877 * xs_destroy - prepare to shutdown a transport 878 * @xprt: doomed transport 879 * 880 */ 881 static void xs_destroy(struct rpc_xprt *xprt) 882 { 883 struct sock_xprt *transport = container_of(xprt, 884 struct sock_xprt, xprt); 885 dprintk("RPC: xs_destroy xprt %p\n", xprt); 886 887 cancel_delayed_work_sync(&transport->connect_worker); 888 xs_close(xprt); 889 xs_xprt_free(xprt); 890 module_put(THIS_MODULE); 891 } 892 893 static int xs_local_copy_to_xdr(struct xdr_buf *xdr, struct sk_buff *skb) 894 { 895 struct xdr_skb_reader desc = { 896 .skb = skb, 897 .offset = sizeof(rpc_fraghdr), 898 .count = skb->len - sizeof(rpc_fraghdr), 899 }; 900 901 if (xdr_partial_copy_from_skb(xdr, 0, &desc, xdr_skb_read_bits) < 0) 902 return -1; 903 if (desc.count) 904 return -1; 905 return 0; 906 } 907 908 /** 909 * xs_local_data_ready - "data ready" callback for AF_LOCAL sockets 910 * @sk: socket with data to read 911 * 912 * Currently this assumes we can read the whole reply in a single gulp. 913 */ 914 static void xs_local_data_ready(struct sock *sk) 915 { 916 struct rpc_task *task; 917 struct rpc_xprt *xprt; 918 struct rpc_rqst *rovr; 919 struct sk_buff *skb; 920 int err, repsize, copied; 921 u32 _xid; 922 __be32 *xp; 923 924 read_lock_bh(&sk->sk_callback_lock); 925 dprintk("RPC: %s...\n", __func__); 926 xprt = xprt_from_sock(sk); 927 if (xprt == NULL) 928 goto out; 929 930 skb = skb_recv_datagram(sk, 0, 1, &err); 931 if (skb == NULL) 932 goto out; 933 934 repsize = skb->len - sizeof(rpc_fraghdr); 935 if (repsize < 4) { 936 dprintk("RPC: impossible RPC reply size %d\n", repsize); 937 goto dropit; 938 } 939 940 /* Copy the XID from the skb... */ 941 xp = skb_header_pointer(skb, sizeof(rpc_fraghdr), sizeof(_xid), &_xid); 942 if (xp == NULL) 943 goto dropit; 944 945 /* Look up and lock the request corresponding to the given XID */ 946 spin_lock(&xprt->transport_lock); 947 rovr = xprt_lookup_rqst(xprt, *xp); 948 if (!rovr) 949 goto out_unlock; 950 task = rovr->rq_task; 951 952 copied = rovr->rq_private_buf.buflen; 953 if (copied > repsize) 954 copied = repsize; 955 956 if (xs_local_copy_to_xdr(&rovr->rq_private_buf, skb)) { 957 dprintk("RPC: sk_buff copy failed\n"); 958 goto out_unlock; 959 } 960 961 xprt_complete_rqst(task, copied); 962 963 out_unlock: 964 spin_unlock(&xprt->transport_lock); 965 dropit: 966 skb_free_datagram(sk, skb); 967 out: 968 read_unlock_bh(&sk->sk_callback_lock); 969 } 970 971 /** 972 * xs_udp_data_ready - "data ready" callback for UDP sockets 973 * @sk: socket with data to read 974 * 975 */ 976 static void xs_udp_data_ready(struct sock *sk) 977 { 978 struct rpc_task *task; 979 struct rpc_xprt *xprt; 980 struct rpc_rqst *rovr; 981 struct sk_buff *skb; 982 int err, repsize, copied; 983 u32 _xid; 984 __be32 *xp; 985 986 read_lock_bh(&sk->sk_callback_lock); 987 dprintk("RPC: xs_udp_data_ready...\n"); 988 if (!(xprt = xprt_from_sock(sk))) 989 goto out; 990 991 if ((skb = skb_recv_datagram(sk, 0, 1, &err)) == NULL) 992 goto out; 993 994 repsize = skb->len - sizeof(struct udphdr); 995 if (repsize < 4) { 996 dprintk("RPC: impossible RPC reply size %d!\n", repsize); 997 goto dropit; 998 } 999 1000 /* Copy the XID from the skb... */ 1001 xp = skb_header_pointer(skb, sizeof(struct udphdr), 1002 sizeof(_xid), &_xid); 1003 if (xp == NULL) 1004 goto dropit; 1005 1006 /* Look up and lock the request corresponding to the given XID */ 1007 spin_lock(&xprt->transport_lock); 1008 rovr = xprt_lookup_rqst(xprt, *xp); 1009 if (!rovr) 1010 goto out_unlock; 1011 task = rovr->rq_task; 1012 1013 if ((copied = rovr->rq_private_buf.buflen) > repsize) 1014 copied = repsize; 1015 1016 /* Suck it into the iovec, verify checksum if not done by hw. */ 1017 if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb)) { 1018 UDPX_INC_STATS_BH(sk, UDP_MIB_INERRORS); 1019 goto out_unlock; 1020 } 1021 1022 UDPX_INC_STATS_BH(sk, UDP_MIB_INDATAGRAMS); 1023 1024 xprt_adjust_cwnd(xprt, task, copied); 1025 xprt_complete_rqst(task, copied); 1026 1027 out_unlock: 1028 spin_unlock(&xprt->transport_lock); 1029 dropit: 1030 skb_free_datagram(sk, skb); 1031 out: 1032 read_unlock_bh(&sk->sk_callback_lock); 1033 } 1034 1035 /* 1036 * Helper function to force a TCP close if the server is sending 1037 * junk and/or it has put us in CLOSE_WAIT 1038 */ 1039 static void xs_tcp_force_close(struct rpc_xprt *xprt) 1040 { 1041 xprt_force_disconnect(xprt); 1042 } 1043 1044 static inline void xs_tcp_read_fraghdr(struct rpc_xprt *xprt, struct xdr_skb_reader *desc) 1045 { 1046 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); 1047 size_t len, used; 1048 char *p; 1049 1050 p = ((char *) &transport->tcp_fraghdr) + transport->tcp_offset; 1051 len = sizeof(transport->tcp_fraghdr) - transport->tcp_offset; 1052 used = xdr_skb_read_bits(desc, p, len); 1053 transport->tcp_offset += used; 1054 if (used != len) 1055 return; 1056 1057 transport->tcp_reclen = ntohl(transport->tcp_fraghdr); 1058 if (transport->tcp_reclen & RPC_LAST_STREAM_FRAGMENT) 1059 transport->tcp_flags |= TCP_RCV_LAST_FRAG; 1060 else 1061 transport->tcp_flags &= ~TCP_RCV_LAST_FRAG; 1062 transport->tcp_reclen &= RPC_FRAGMENT_SIZE_MASK; 1063 1064 transport->tcp_flags &= ~TCP_RCV_COPY_FRAGHDR; 1065 transport->tcp_offset = 0; 1066 1067 /* Sanity check of the record length */ 1068 if (unlikely(transport->tcp_reclen < 8)) { 1069 dprintk("RPC: invalid TCP record fragment length\n"); 1070 xs_tcp_force_close(xprt); 1071 return; 1072 } 1073 dprintk("RPC: reading TCP record fragment of length %d\n", 1074 transport->tcp_reclen); 1075 } 1076 1077 static void xs_tcp_check_fraghdr(struct sock_xprt *transport) 1078 { 1079 if (transport->tcp_offset == transport->tcp_reclen) { 1080 transport->tcp_flags |= TCP_RCV_COPY_FRAGHDR; 1081 transport->tcp_offset = 0; 1082 if (transport->tcp_flags & TCP_RCV_LAST_FRAG) { 1083 transport->tcp_flags &= ~TCP_RCV_COPY_DATA; 1084 transport->tcp_flags |= TCP_RCV_COPY_XID; 1085 transport->tcp_copied = 0; 1086 } 1087 } 1088 } 1089 1090 static inline void xs_tcp_read_xid(struct sock_xprt *transport, struct xdr_skb_reader *desc) 1091 { 1092 size_t len, used; 1093 char *p; 1094 1095 len = sizeof(transport->tcp_xid) - transport->tcp_offset; 1096 dprintk("RPC: reading XID (%Zu bytes)\n", len); 1097 p = ((char *) &transport->tcp_xid) + transport->tcp_offset; 1098 used = xdr_skb_read_bits(desc, p, len); 1099 transport->tcp_offset += used; 1100 if (used != len) 1101 return; 1102 transport->tcp_flags &= ~TCP_RCV_COPY_XID; 1103 transport->tcp_flags |= TCP_RCV_READ_CALLDIR; 1104 transport->tcp_copied = 4; 1105 dprintk("RPC: reading %s XID %08x\n", 1106 (transport->tcp_flags & TCP_RPC_REPLY) ? "reply for" 1107 : "request with", 1108 ntohl(transport->tcp_xid)); 1109 xs_tcp_check_fraghdr(transport); 1110 } 1111 1112 static inline void xs_tcp_read_calldir(struct sock_xprt *transport, 1113 struct xdr_skb_reader *desc) 1114 { 1115 size_t len, used; 1116 u32 offset; 1117 char *p; 1118 1119 /* 1120 * We want transport->tcp_offset to be 8 at the end of this routine 1121 * (4 bytes for the xid and 4 bytes for the call/reply flag). 1122 * When this function is called for the first time, 1123 * transport->tcp_offset is 4 (after having already read the xid). 1124 */ 1125 offset = transport->tcp_offset - sizeof(transport->tcp_xid); 1126 len = sizeof(transport->tcp_calldir) - offset; 1127 dprintk("RPC: reading CALL/REPLY flag (%Zu bytes)\n", len); 1128 p = ((char *) &transport->tcp_calldir) + offset; 1129 used = xdr_skb_read_bits(desc, p, len); 1130 transport->tcp_offset += used; 1131 if (used != len) 1132 return; 1133 transport->tcp_flags &= ~TCP_RCV_READ_CALLDIR; 1134 /* 1135 * We don't yet have the XDR buffer, so we will write the calldir 1136 * out after we get the buffer from the 'struct rpc_rqst' 1137 */ 1138 switch (ntohl(transport->tcp_calldir)) { 1139 case RPC_REPLY: 1140 transport->tcp_flags |= TCP_RCV_COPY_CALLDIR; 1141 transport->tcp_flags |= TCP_RCV_COPY_DATA; 1142 transport->tcp_flags |= TCP_RPC_REPLY; 1143 break; 1144 case RPC_CALL: 1145 transport->tcp_flags |= TCP_RCV_COPY_CALLDIR; 1146 transport->tcp_flags |= TCP_RCV_COPY_DATA; 1147 transport->tcp_flags &= ~TCP_RPC_REPLY; 1148 break; 1149 default: 1150 dprintk("RPC: invalid request message type\n"); 1151 xs_tcp_force_close(&transport->xprt); 1152 } 1153 xs_tcp_check_fraghdr(transport); 1154 } 1155 1156 static inline void xs_tcp_read_common(struct rpc_xprt *xprt, 1157 struct xdr_skb_reader *desc, 1158 struct rpc_rqst *req) 1159 { 1160 struct sock_xprt *transport = 1161 container_of(xprt, struct sock_xprt, xprt); 1162 struct xdr_buf *rcvbuf; 1163 size_t len; 1164 ssize_t r; 1165 1166 rcvbuf = &req->rq_private_buf; 1167 1168 if (transport->tcp_flags & TCP_RCV_COPY_CALLDIR) { 1169 /* 1170 * Save the RPC direction in the XDR buffer 1171 */ 1172 memcpy(rcvbuf->head[0].iov_base + transport->tcp_copied, 1173 &transport->tcp_calldir, 1174 sizeof(transport->tcp_calldir)); 1175 transport->tcp_copied += sizeof(transport->tcp_calldir); 1176 transport->tcp_flags &= ~TCP_RCV_COPY_CALLDIR; 1177 } 1178 1179 len = desc->count; 1180 if (len > transport->tcp_reclen - transport->tcp_offset) { 1181 struct xdr_skb_reader my_desc; 1182 1183 len = transport->tcp_reclen - transport->tcp_offset; 1184 memcpy(&my_desc, desc, sizeof(my_desc)); 1185 my_desc.count = len; 1186 r = xdr_partial_copy_from_skb(rcvbuf, transport->tcp_copied, 1187 &my_desc, xdr_skb_read_bits); 1188 desc->count -= r; 1189 desc->offset += r; 1190 } else 1191 r = xdr_partial_copy_from_skb(rcvbuf, transport->tcp_copied, 1192 desc, xdr_skb_read_bits); 1193 1194 if (r > 0) { 1195 transport->tcp_copied += r; 1196 transport->tcp_offset += r; 1197 } 1198 if (r != len) { 1199 /* Error when copying to the receive buffer, 1200 * usually because we weren't able to allocate 1201 * additional buffer pages. All we can do now 1202 * is turn off TCP_RCV_COPY_DATA, so the request 1203 * will not receive any additional updates, 1204 * and time out. 1205 * Any remaining data from this record will 1206 * be discarded. 1207 */ 1208 transport->tcp_flags &= ~TCP_RCV_COPY_DATA; 1209 dprintk("RPC: XID %08x truncated request\n", 1210 ntohl(transport->tcp_xid)); 1211 dprintk("RPC: xprt = %p, tcp_copied = %lu, " 1212 "tcp_offset = %u, tcp_reclen = %u\n", 1213 xprt, transport->tcp_copied, 1214 transport->tcp_offset, transport->tcp_reclen); 1215 return; 1216 } 1217 1218 dprintk("RPC: XID %08x read %Zd bytes\n", 1219 ntohl(transport->tcp_xid), r); 1220 dprintk("RPC: xprt = %p, tcp_copied = %lu, tcp_offset = %u, " 1221 "tcp_reclen = %u\n", xprt, transport->tcp_copied, 1222 transport->tcp_offset, transport->tcp_reclen); 1223 1224 if (transport->tcp_copied == req->rq_private_buf.buflen) 1225 transport->tcp_flags &= ~TCP_RCV_COPY_DATA; 1226 else if (transport->tcp_offset == transport->tcp_reclen) { 1227 if (transport->tcp_flags & TCP_RCV_LAST_FRAG) 1228 transport->tcp_flags &= ~TCP_RCV_COPY_DATA; 1229 } 1230 } 1231 1232 /* 1233 * Finds the request corresponding to the RPC xid and invokes the common 1234 * tcp read code to read the data. 1235 */ 1236 static inline int xs_tcp_read_reply(struct rpc_xprt *xprt, 1237 struct xdr_skb_reader *desc) 1238 { 1239 struct sock_xprt *transport = 1240 container_of(xprt, struct sock_xprt, xprt); 1241 struct rpc_rqst *req; 1242 1243 dprintk("RPC: read reply XID %08x\n", ntohl(transport->tcp_xid)); 1244 1245 /* Find and lock the request corresponding to this xid */ 1246 spin_lock(&xprt->transport_lock); 1247 req = xprt_lookup_rqst(xprt, transport->tcp_xid); 1248 if (!req) { 1249 dprintk("RPC: XID %08x request not found!\n", 1250 ntohl(transport->tcp_xid)); 1251 spin_unlock(&xprt->transport_lock); 1252 return -1; 1253 } 1254 1255 xs_tcp_read_common(xprt, desc, req); 1256 1257 if (!(transport->tcp_flags & TCP_RCV_COPY_DATA)) 1258 xprt_complete_rqst(req->rq_task, transport->tcp_copied); 1259 1260 spin_unlock(&xprt->transport_lock); 1261 return 0; 1262 } 1263 1264 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 1265 /* 1266 * Obtains an rpc_rqst previously allocated and invokes the common 1267 * tcp read code to read the data. The result is placed in the callback 1268 * queue. 1269 * If we're unable to obtain the rpc_rqst we schedule the closing of the 1270 * connection and return -1. 1271 */ 1272 static int xs_tcp_read_callback(struct rpc_xprt *xprt, 1273 struct xdr_skb_reader *desc) 1274 { 1275 struct sock_xprt *transport = 1276 container_of(xprt, struct sock_xprt, xprt); 1277 struct rpc_rqst *req; 1278 1279 /* Look up and lock the request corresponding to the given XID */ 1280 spin_lock(&xprt->transport_lock); 1281 req = xprt_lookup_bc_request(xprt, transport->tcp_xid); 1282 if (req == NULL) { 1283 spin_unlock(&xprt->transport_lock); 1284 printk(KERN_WARNING "Callback slot table overflowed\n"); 1285 xprt_force_disconnect(xprt); 1286 return -1; 1287 } 1288 1289 dprintk("RPC: read callback XID %08x\n", ntohl(req->rq_xid)); 1290 xs_tcp_read_common(xprt, desc, req); 1291 1292 if (!(transport->tcp_flags & TCP_RCV_COPY_DATA)) 1293 xprt_complete_bc_request(req, transport->tcp_copied); 1294 spin_unlock(&xprt->transport_lock); 1295 1296 return 0; 1297 } 1298 1299 static inline int _xs_tcp_read_data(struct rpc_xprt *xprt, 1300 struct xdr_skb_reader *desc) 1301 { 1302 struct sock_xprt *transport = 1303 container_of(xprt, struct sock_xprt, xprt); 1304 1305 return (transport->tcp_flags & TCP_RPC_REPLY) ? 1306 xs_tcp_read_reply(xprt, desc) : 1307 xs_tcp_read_callback(xprt, desc); 1308 } 1309 #else 1310 static inline int _xs_tcp_read_data(struct rpc_xprt *xprt, 1311 struct xdr_skb_reader *desc) 1312 { 1313 return xs_tcp_read_reply(xprt, desc); 1314 } 1315 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 1316 1317 /* 1318 * Read data off the transport. This can be either an RPC_CALL or an 1319 * RPC_REPLY. Relay the processing to helper functions. 1320 */ 1321 static void xs_tcp_read_data(struct rpc_xprt *xprt, 1322 struct xdr_skb_reader *desc) 1323 { 1324 struct sock_xprt *transport = 1325 container_of(xprt, struct sock_xprt, xprt); 1326 1327 if (_xs_tcp_read_data(xprt, desc) == 0) 1328 xs_tcp_check_fraghdr(transport); 1329 else { 1330 /* 1331 * The transport_lock protects the request handling. 1332 * There's no need to hold it to update the tcp_flags. 1333 */ 1334 transport->tcp_flags &= ~TCP_RCV_COPY_DATA; 1335 } 1336 } 1337 1338 static inline void xs_tcp_read_discard(struct sock_xprt *transport, struct xdr_skb_reader *desc) 1339 { 1340 size_t len; 1341 1342 len = transport->tcp_reclen - transport->tcp_offset; 1343 if (len > desc->count) 1344 len = desc->count; 1345 desc->count -= len; 1346 desc->offset += len; 1347 transport->tcp_offset += len; 1348 dprintk("RPC: discarded %Zu bytes\n", len); 1349 xs_tcp_check_fraghdr(transport); 1350 } 1351 1352 static int xs_tcp_data_recv(read_descriptor_t *rd_desc, struct sk_buff *skb, unsigned int offset, size_t len) 1353 { 1354 struct rpc_xprt *xprt = rd_desc->arg.data; 1355 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); 1356 struct xdr_skb_reader desc = { 1357 .skb = skb, 1358 .offset = offset, 1359 .count = len, 1360 }; 1361 1362 dprintk("RPC: xs_tcp_data_recv started\n"); 1363 do { 1364 trace_xs_tcp_data_recv(transport); 1365 /* Read in a new fragment marker if necessary */ 1366 /* Can we ever really expect to get completely empty fragments? */ 1367 if (transport->tcp_flags & TCP_RCV_COPY_FRAGHDR) { 1368 xs_tcp_read_fraghdr(xprt, &desc); 1369 continue; 1370 } 1371 /* Read in the xid if necessary */ 1372 if (transport->tcp_flags & TCP_RCV_COPY_XID) { 1373 xs_tcp_read_xid(transport, &desc); 1374 continue; 1375 } 1376 /* Read in the call/reply flag */ 1377 if (transport->tcp_flags & TCP_RCV_READ_CALLDIR) { 1378 xs_tcp_read_calldir(transport, &desc); 1379 continue; 1380 } 1381 /* Read in the request data */ 1382 if (transport->tcp_flags & TCP_RCV_COPY_DATA) { 1383 xs_tcp_read_data(xprt, &desc); 1384 continue; 1385 } 1386 /* Skip over any trailing bytes on short reads */ 1387 xs_tcp_read_discard(transport, &desc); 1388 } while (desc.count); 1389 trace_xs_tcp_data_recv(transport); 1390 dprintk("RPC: xs_tcp_data_recv done\n"); 1391 return len - desc.count; 1392 } 1393 1394 /** 1395 * xs_tcp_data_ready - "data ready" callback for TCP sockets 1396 * @sk: socket with data to read 1397 * 1398 */ 1399 static void xs_tcp_data_ready(struct sock *sk) 1400 { 1401 struct rpc_xprt *xprt; 1402 read_descriptor_t rd_desc; 1403 int read; 1404 unsigned long total = 0; 1405 1406 dprintk("RPC: xs_tcp_data_ready...\n"); 1407 1408 read_lock_bh(&sk->sk_callback_lock); 1409 if (!(xprt = xprt_from_sock(sk))) { 1410 read = 0; 1411 goto out; 1412 } 1413 /* Any data means we had a useful conversation, so 1414 * the we don't need to delay the next reconnect 1415 */ 1416 if (xprt->reestablish_timeout) 1417 xprt->reestablish_timeout = 0; 1418 1419 /* We use rd_desc to pass struct xprt to xs_tcp_data_recv */ 1420 rd_desc.arg.data = xprt; 1421 do { 1422 rd_desc.count = 65536; 1423 read = tcp_read_sock(sk, &rd_desc, xs_tcp_data_recv); 1424 if (read > 0) 1425 total += read; 1426 } while (read > 0); 1427 out: 1428 trace_xs_tcp_data_ready(xprt, read, total); 1429 read_unlock_bh(&sk->sk_callback_lock); 1430 } 1431 1432 /** 1433 * xs_tcp_state_change - callback to handle TCP socket state changes 1434 * @sk: socket whose state has changed 1435 * 1436 */ 1437 static void xs_tcp_state_change(struct sock *sk) 1438 { 1439 struct rpc_xprt *xprt; 1440 struct sock_xprt *transport; 1441 1442 read_lock_bh(&sk->sk_callback_lock); 1443 if (!(xprt = xprt_from_sock(sk))) 1444 goto out; 1445 dprintk("RPC: xs_tcp_state_change client %p...\n", xprt); 1446 dprintk("RPC: state %x conn %d dead %d zapped %d sk_shutdown %d\n", 1447 sk->sk_state, xprt_connected(xprt), 1448 sock_flag(sk, SOCK_DEAD), 1449 sock_flag(sk, SOCK_ZAPPED), 1450 sk->sk_shutdown); 1451 1452 transport = container_of(xprt, struct sock_xprt, xprt); 1453 trace_rpc_socket_state_change(xprt, sk->sk_socket); 1454 switch (sk->sk_state) { 1455 case TCP_ESTABLISHED: 1456 spin_lock(&xprt->transport_lock); 1457 if (!xprt_test_and_set_connected(xprt)) { 1458 1459 /* Reset TCP record info */ 1460 transport->tcp_offset = 0; 1461 transport->tcp_reclen = 0; 1462 transport->tcp_copied = 0; 1463 transport->tcp_flags = 1464 TCP_RCV_COPY_FRAGHDR | TCP_RCV_COPY_XID; 1465 xprt->connect_cookie++; 1466 clear_bit(XPRT_SOCK_CONNECTING, &transport->sock_state); 1467 xprt_clear_connecting(xprt); 1468 1469 xprt_wake_pending_tasks(xprt, -EAGAIN); 1470 } 1471 spin_unlock(&xprt->transport_lock); 1472 break; 1473 case TCP_FIN_WAIT1: 1474 /* The client initiated a shutdown of the socket */ 1475 xprt->connect_cookie++; 1476 xprt->reestablish_timeout = 0; 1477 set_bit(XPRT_CLOSING, &xprt->state); 1478 smp_mb__before_atomic(); 1479 clear_bit(XPRT_CONNECTED, &xprt->state); 1480 clear_bit(XPRT_CLOSE_WAIT, &xprt->state); 1481 smp_mb__after_atomic(); 1482 break; 1483 case TCP_CLOSE_WAIT: 1484 /* The server initiated a shutdown of the socket */ 1485 xprt->connect_cookie++; 1486 clear_bit(XPRT_CONNECTED, &xprt->state); 1487 xs_tcp_force_close(xprt); 1488 case TCP_CLOSING: 1489 /* 1490 * If the server closed down the connection, make sure that 1491 * we back off before reconnecting 1492 */ 1493 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO) 1494 xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO; 1495 break; 1496 case TCP_LAST_ACK: 1497 set_bit(XPRT_CLOSING, &xprt->state); 1498 smp_mb__before_atomic(); 1499 clear_bit(XPRT_CONNECTED, &xprt->state); 1500 smp_mb__after_atomic(); 1501 break; 1502 case TCP_CLOSE: 1503 if (test_and_clear_bit(XPRT_SOCK_CONNECTING, 1504 &transport->sock_state)) 1505 xprt_clear_connecting(xprt); 1506 xs_sock_mark_closed(xprt); 1507 } 1508 out: 1509 read_unlock_bh(&sk->sk_callback_lock); 1510 } 1511 1512 static void xs_write_space(struct sock *sk) 1513 { 1514 struct socket *sock; 1515 struct rpc_xprt *xprt; 1516 1517 if (unlikely(!(sock = sk->sk_socket))) 1518 return; 1519 clear_bit(SOCK_NOSPACE, &sock->flags); 1520 1521 if (unlikely(!(xprt = xprt_from_sock(sk)))) 1522 return; 1523 if (test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sock->flags) == 0) 1524 return; 1525 1526 xprt_write_space(xprt); 1527 } 1528 1529 /** 1530 * xs_udp_write_space - callback invoked when socket buffer space 1531 * becomes available 1532 * @sk: socket whose state has changed 1533 * 1534 * Called when more output buffer space is available for this socket. 1535 * We try not to wake our writers until they can make "significant" 1536 * progress, otherwise we'll waste resources thrashing kernel_sendmsg 1537 * with a bunch of small requests. 1538 */ 1539 static void xs_udp_write_space(struct sock *sk) 1540 { 1541 read_lock_bh(&sk->sk_callback_lock); 1542 1543 /* from net/core/sock.c:sock_def_write_space */ 1544 if (sock_writeable(sk)) 1545 xs_write_space(sk); 1546 1547 read_unlock_bh(&sk->sk_callback_lock); 1548 } 1549 1550 /** 1551 * xs_tcp_write_space - callback invoked when socket buffer space 1552 * becomes available 1553 * @sk: socket whose state has changed 1554 * 1555 * Called when more output buffer space is available for this socket. 1556 * We try not to wake our writers until they can make "significant" 1557 * progress, otherwise we'll waste resources thrashing kernel_sendmsg 1558 * with a bunch of small requests. 1559 */ 1560 static void xs_tcp_write_space(struct sock *sk) 1561 { 1562 read_lock_bh(&sk->sk_callback_lock); 1563 1564 /* from net/core/stream.c:sk_stream_write_space */ 1565 if (sk_stream_is_writeable(sk)) 1566 xs_write_space(sk); 1567 1568 read_unlock_bh(&sk->sk_callback_lock); 1569 } 1570 1571 static void xs_udp_do_set_buffer_size(struct rpc_xprt *xprt) 1572 { 1573 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); 1574 struct sock *sk = transport->inet; 1575 1576 if (transport->rcvsize) { 1577 sk->sk_userlocks |= SOCK_RCVBUF_LOCK; 1578 sk->sk_rcvbuf = transport->rcvsize * xprt->max_reqs * 2; 1579 } 1580 if (transport->sndsize) { 1581 sk->sk_userlocks |= SOCK_SNDBUF_LOCK; 1582 sk->sk_sndbuf = transport->sndsize * xprt->max_reqs * 2; 1583 sk->sk_write_space(sk); 1584 } 1585 } 1586 1587 /** 1588 * xs_udp_set_buffer_size - set send and receive limits 1589 * @xprt: generic transport 1590 * @sndsize: requested size of send buffer, in bytes 1591 * @rcvsize: requested size of receive buffer, in bytes 1592 * 1593 * Set socket send and receive buffer size limits. 1594 */ 1595 static void xs_udp_set_buffer_size(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize) 1596 { 1597 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); 1598 1599 transport->sndsize = 0; 1600 if (sndsize) 1601 transport->sndsize = sndsize + 1024; 1602 transport->rcvsize = 0; 1603 if (rcvsize) 1604 transport->rcvsize = rcvsize + 1024; 1605 1606 xs_udp_do_set_buffer_size(xprt); 1607 } 1608 1609 /** 1610 * xs_udp_timer - called when a retransmit timeout occurs on a UDP transport 1611 * @task: task that timed out 1612 * 1613 * Adjust the congestion window after a retransmit timeout has occurred. 1614 */ 1615 static void xs_udp_timer(struct rpc_xprt *xprt, struct rpc_task *task) 1616 { 1617 xprt_adjust_cwnd(xprt, task, -ETIMEDOUT); 1618 } 1619 1620 static unsigned short xs_get_random_port(void) 1621 { 1622 unsigned short range = xprt_max_resvport - xprt_min_resvport; 1623 unsigned short rand = (unsigned short) prandom_u32() % range; 1624 return rand + xprt_min_resvport; 1625 } 1626 1627 /** 1628 * xs_set_reuseaddr_port - set the socket's port and address reuse options 1629 * @sock: socket 1630 * 1631 * Note that this function has to be called on all sockets that share the 1632 * same port, and it must be called before binding. 1633 */ 1634 static void xs_sock_set_reuseport(struct socket *sock) 1635 { 1636 int opt = 1; 1637 1638 kernel_setsockopt(sock, SOL_SOCKET, SO_REUSEPORT, 1639 (char *)&opt, sizeof(opt)); 1640 } 1641 1642 static unsigned short xs_sock_getport(struct socket *sock) 1643 { 1644 struct sockaddr_storage buf; 1645 int buflen; 1646 unsigned short port = 0; 1647 1648 if (kernel_getsockname(sock, (struct sockaddr *)&buf, &buflen) < 0) 1649 goto out; 1650 switch (buf.ss_family) { 1651 case AF_INET6: 1652 port = ntohs(((struct sockaddr_in6 *)&buf)->sin6_port); 1653 break; 1654 case AF_INET: 1655 port = ntohs(((struct sockaddr_in *)&buf)->sin_port); 1656 } 1657 out: 1658 return port; 1659 } 1660 1661 /** 1662 * xs_set_port - reset the port number in the remote endpoint address 1663 * @xprt: generic transport 1664 * @port: new port number 1665 * 1666 */ 1667 static void xs_set_port(struct rpc_xprt *xprt, unsigned short port) 1668 { 1669 dprintk("RPC: setting port for xprt %p to %u\n", xprt, port); 1670 1671 rpc_set_port(xs_addr(xprt), port); 1672 xs_update_peer_port(xprt); 1673 } 1674 1675 static void xs_set_srcport(struct sock_xprt *transport, struct socket *sock) 1676 { 1677 if (transport->srcport == 0) 1678 transport->srcport = xs_sock_getport(sock); 1679 } 1680 1681 static unsigned short xs_get_srcport(struct sock_xprt *transport) 1682 { 1683 unsigned short port = transport->srcport; 1684 1685 if (port == 0 && transport->xprt.resvport) 1686 port = xs_get_random_port(); 1687 return port; 1688 } 1689 1690 static unsigned short xs_next_srcport(struct sock_xprt *transport, unsigned short port) 1691 { 1692 if (transport->srcport != 0) 1693 transport->srcport = 0; 1694 if (!transport->xprt.resvport) 1695 return 0; 1696 if (port <= xprt_min_resvport || port > xprt_max_resvport) 1697 return xprt_max_resvport; 1698 return --port; 1699 } 1700 static int xs_bind(struct sock_xprt *transport, struct socket *sock) 1701 { 1702 struct sockaddr_storage myaddr; 1703 int err, nloop = 0; 1704 unsigned short port = xs_get_srcport(transport); 1705 unsigned short last; 1706 1707 /* 1708 * If we are asking for any ephemeral port (i.e. port == 0 && 1709 * transport->xprt.resvport == 0), don't bind. Let the local 1710 * port selection happen implicitly when the socket is used 1711 * (for example at connect time). 1712 * 1713 * This ensures that we can continue to establish TCP 1714 * connections even when all local ephemeral ports are already 1715 * a part of some TCP connection. This makes no difference 1716 * for UDP sockets, but also doens't harm them. 1717 * 1718 * If we're asking for any reserved port (i.e. port == 0 && 1719 * transport->xprt.resvport == 1) xs_get_srcport above will 1720 * ensure that port is non-zero and we will bind as needed. 1721 */ 1722 if (port == 0) 1723 return 0; 1724 1725 memcpy(&myaddr, &transport->srcaddr, transport->xprt.addrlen); 1726 do { 1727 rpc_set_port((struct sockaddr *)&myaddr, port); 1728 err = kernel_bind(sock, (struct sockaddr *)&myaddr, 1729 transport->xprt.addrlen); 1730 if (err == 0) { 1731 transport->srcport = port; 1732 break; 1733 } 1734 last = port; 1735 port = xs_next_srcport(transport, port); 1736 if (port > last) 1737 nloop++; 1738 } while (err == -EADDRINUSE && nloop != 2); 1739 1740 if (myaddr.ss_family == AF_INET) 1741 dprintk("RPC: %s %pI4:%u: %s (%d)\n", __func__, 1742 &((struct sockaddr_in *)&myaddr)->sin_addr, 1743 port, err ? "failed" : "ok", err); 1744 else 1745 dprintk("RPC: %s %pI6:%u: %s (%d)\n", __func__, 1746 &((struct sockaddr_in6 *)&myaddr)->sin6_addr, 1747 port, err ? "failed" : "ok", err); 1748 return err; 1749 } 1750 1751 /* 1752 * We don't support autobind on AF_LOCAL sockets 1753 */ 1754 static void xs_local_rpcbind(struct rpc_task *task) 1755 { 1756 rcu_read_lock(); 1757 xprt_set_bound(rcu_dereference(task->tk_client->cl_xprt)); 1758 rcu_read_unlock(); 1759 } 1760 1761 static void xs_local_set_port(struct rpc_xprt *xprt, unsigned short port) 1762 { 1763 } 1764 1765 #ifdef CONFIG_DEBUG_LOCK_ALLOC 1766 static struct lock_class_key xs_key[2]; 1767 static struct lock_class_key xs_slock_key[2]; 1768 1769 static inline void xs_reclassify_socketu(struct socket *sock) 1770 { 1771 struct sock *sk = sock->sk; 1772 1773 sock_lock_init_class_and_name(sk, "slock-AF_LOCAL-RPC", 1774 &xs_slock_key[1], "sk_lock-AF_LOCAL-RPC", &xs_key[1]); 1775 } 1776 1777 static inline void xs_reclassify_socket4(struct socket *sock) 1778 { 1779 struct sock *sk = sock->sk; 1780 1781 sock_lock_init_class_and_name(sk, "slock-AF_INET-RPC", 1782 &xs_slock_key[0], "sk_lock-AF_INET-RPC", &xs_key[0]); 1783 } 1784 1785 static inline void xs_reclassify_socket6(struct socket *sock) 1786 { 1787 struct sock *sk = sock->sk; 1788 1789 sock_lock_init_class_and_name(sk, "slock-AF_INET6-RPC", 1790 &xs_slock_key[1], "sk_lock-AF_INET6-RPC", &xs_key[1]); 1791 } 1792 1793 static inline void xs_reclassify_socket(int family, struct socket *sock) 1794 { 1795 WARN_ON_ONCE(sock_owned_by_user(sock->sk)); 1796 if (sock_owned_by_user(sock->sk)) 1797 return; 1798 1799 switch (family) { 1800 case AF_LOCAL: 1801 xs_reclassify_socketu(sock); 1802 break; 1803 case AF_INET: 1804 xs_reclassify_socket4(sock); 1805 break; 1806 case AF_INET6: 1807 xs_reclassify_socket6(sock); 1808 break; 1809 } 1810 } 1811 #else 1812 static inline void xs_reclassify_socketu(struct socket *sock) 1813 { 1814 } 1815 1816 static inline void xs_reclassify_socket4(struct socket *sock) 1817 { 1818 } 1819 1820 static inline void xs_reclassify_socket6(struct socket *sock) 1821 { 1822 } 1823 1824 static inline void xs_reclassify_socket(int family, struct socket *sock) 1825 { 1826 } 1827 #endif 1828 1829 static void xs_dummy_setup_socket(struct work_struct *work) 1830 { 1831 } 1832 1833 static struct socket *xs_create_sock(struct rpc_xprt *xprt, 1834 struct sock_xprt *transport, int family, int type, 1835 int protocol, bool reuseport) 1836 { 1837 struct socket *sock; 1838 int err; 1839 1840 err = __sock_create(xprt->xprt_net, family, type, protocol, &sock, 1); 1841 if (err < 0) { 1842 dprintk("RPC: can't create %d transport socket (%d).\n", 1843 protocol, -err); 1844 goto out; 1845 } 1846 xs_reclassify_socket(family, sock); 1847 1848 if (reuseport) 1849 xs_sock_set_reuseport(sock); 1850 1851 err = xs_bind(transport, sock); 1852 if (err) { 1853 sock_release(sock); 1854 goto out; 1855 } 1856 1857 return sock; 1858 out: 1859 return ERR_PTR(err); 1860 } 1861 1862 static int xs_local_finish_connecting(struct rpc_xprt *xprt, 1863 struct socket *sock) 1864 { 1865 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, 1866 xprt); 1867 1868 if (!transport->inet) { 1869 struct sock *sk = sock->sk; 1870 1871 write_lock_bh(&sk->sk_callback_lock); 1872 1873 xs_save_old_callbacks(transport, sk); 1874 1875 sk->sk_user_data = xprt; 1876 sk->sk_data_ready = xs_local_data_ready; 1877 sk->sk_write_space = xs_udp_write_space; 1878 sk->sk_error_report = xs_error_report; 1879 sk->sk_allocation = GFP_NOIO; 1880 1881 xprt_clear_connected(xprt); 1882 1883 /* Reset to new socket */ 1884 transport->sock = sock; 1885 transport->inet = sk; 1886 1887 write_unlock_bh(&sk->sk_callback_lock); 1888 } 1889 1890 /* Tell the socket layer to start connecting... */ 1891 xprt->stat.connect_count++; 1892 xprt->stat.connect_start = jiffies; 1893 return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0); 1894 } 1895 1896 /** 1897 * xs_local_setup_socket - create AF_LOCAL socket, connect to a local endpoint 1898 * @transport: socket transport to connect 1899 */ 1900 static int xs_local_setup_socket(struct sock_xprt *transport) 1901 { 1902 struct rpc_xprt *xprt = &transport->xprt; 1903 struct socket *sock; 1904 int status = -EIO; 1905 1906 status = __sock_create(xprt->xprt_net, AF_LOCAL, 1907 SOCK_STREAM, 0, &sock, 1); 1908 if (status < 0) { 1909 dprintk("RPC: can't create AF_LOCAL " 1910 "transport socket (%d).\n", -status); 1911 goto out; 1912 } 1913 xs_reclassify_socketu(sock); 1914 1915 dprintk("RPC: worker connecting xprt %p via AF_LOCAL to %s\n", 1916 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]); 1917 1918 status = xs_local_finish_connecting(xprt, sock); 1919 trace_rpc_socket_connect(xprt, sock, status); 1920 switch (status) { 1921 case 0: 1922 dprintk("RPC: xprt %p connected to %s\n", 1923 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]); 1924 xprt_set_connected(xprt); 1925 case -ENOBUFS: 1926 break; 1927 case -ENOENT: 1928 dprintk("RPC: xprt %p: socket %s does not exist\n", 1929 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]); 1930 break; 1931 case -ECONNREFUSED: 1932 dprintk("RPC: xprt %p: connection refused for %s\n", 1933 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]); 1934 break; 1935 default: 1936 printk(KERN_ERR "%s: unhandled error (%d) connecting to %s\n", 1937 __func__, -status, 1938 xprt->address_strings[RPC_DISPLAY_ADDR]); 1939 } 1940 1941 out: 1942 xprt_clear_connecting(xprt); 1943 xprt_wake_pending_tasks(xprt, status); 1944 return status; 1945 } 1946 1947 static void xs_local_connect(struct rpc_xprt *xprt, struct rpc_task *task) 1948 { 1949 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); 1950 int ret; 1951 1952 if (RPC_IS_ASYNC(task)) { 1953 /* 1954 * We want the AF_LOCAL connect to be resolved in the 1955 * filesystem namespace of the process making the rpc 1956 * call. Thus we connect synchronously. 1957 * 1958 * If we want to support asynchronous AF_LOCAL calls, 1959 * we'll need to figure out how to pass a namespace to 1960 * connect. 1961 */ 1962 rpc_exit(task, -ENOTCONN); 1963 return; 1964 } 1965 ret = xs_local_setup_socket(transport); 1966 if (ret && !RPC_IS_SOFTCONN(task)) 1967 msleep_interruptible(15000); 1968 } 1969 1970 #if IS_ENABLED(CONFIG_SUNRPC_SWAP) 1971 /* 1972 * Note that this should be called with XPRT_LOCKED held (or when we otherwise 1973 * know that we have exclusive access to the socket), to guard against 1974 * races with xs_reset_transport. 1975 */ 1976 static void xs_set_memalloc(struct rpc_xprt *xprt) 1977 { 1978 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, 1979 xprt); 1980 1981 /* 1982 * If there's no sock, then we have nothing to set. The 1983 * reconnecting process will get it for us. 1984 */ 1985 if (!transport->inet) 1986 return; 1987 if (atomic_read(&xprt->swapper)) 1988 sk_set_memalloc(transport->inet); 1989 } 1990 1991 /** 1992 * xs_enable_swap - Tag this transport as being used for swap. 1993 * @xprt: transport to tag 1994 * 1995 * Take a reference to this transport on behalf of the rpc_clnt, and 1996 * optionally mark it for swapping if it wasn't already. 1997 */ 1998 static int 1999 xs_enable_swap(struct rpc_xprt *xprt) 2000 { 2001 struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt); 2002 2003 if (atomic_inc_return(&xprt->swapper) != 1) 2004 return 0; 2005 if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE)) 2006 return -ERESTARTSYS; 2007 if (xs->inet) 2008 sk_set_memalloc(xs->inet); 2009 xprt_release_xprt(xprt, NULL); 2010 return 0; 2011 } 2012 2013 /** 2014 * xs_disable_swap - Untag this transport as being used for swap. 2015 * @xprt: transport to tag 2016 * 2017 * Drop a "swapper" reference to this xprt on behalf of the rpc_clnt. If the 2018 * swapper refcount goes to 0, untag the socket as a memalloc socket. 2019 */ 2020 static void 2021 xs_disable_swap(struct rpc_xprt *xprt) 2022 { 2023 struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt); 2024 2025 if (!atomic_dec_and_test(&xprt->swapper)) 2026 return; 2027 if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE)) 2028 return; 2029 if (xs->inet) 2030 sk_clear_memalloc(xs->inet); 2031 xprt_release_xprt(xprt, NULL); 2032 } 2033 #else 2034 static void xs_set_memalloc(struct rpc_xprt *xprt) 2035 { 2036 } 2037 2038 static int 2039 xs_enable_swap(struct rpc_xprt *xprt) 2040 { 2041 return -EINVAL; 2042 } 2043 2044 static void 2045 xs_disable_swap(struct rpc_xprt *xprt) 2046 { 2047 } 2048 #endif 2049 2050 static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock) 2051 { 2052 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); 2053 2054 if (!transport->inet) { 2055 struct sock *sk = sock->sk; 2056 2057 write_lock_bh(&sk->sk_callback_lock); 2058 2059 xs_save_old_callbacks(transport, sk); 2060 2061 sk->sk_user_data = xprt; 2062 sk->sk_data_ready = xs_udp_data_ready; 2063 sk->sk_write_space = xs_udp_write_space; 2064 sk->sk_allocation = GFP_NOIO; 2065 2066 xprt_set_connected(xprt); 2067 2068 /* Reset to new socket */ 2069 transport->sock = sock; 2070 transport->inet = sk; 2071 2072 xs_set_memalloc(xprt); 2073 2074 write_unlock_bh(&sk->sk_callback_lock); 2075 } 2076 xs_udp_do_set_buffer_size(xprt); 2077 } 2078 2079 static void xs_udp_setup_socket(struct work_struct *work) 2080 { 2081 struct sock_xprt *transport = 2082 container_of(work, struct sock_xprt, connect_worker.work); 2083 struct rpc_xprt *xprt = &transport->xprt; 2084 struct socket *sock = transport->sock; 2085 int status = -EIO; 2086 2087 sock = xs_create_sock(xprt, transport, 2088 xs_addr(xprt)->sa_family, SOCK_DGRAM, 2089 IPPROTO_UDP, false); 2090 if (IS_ERR(sock)) 2091 goto out; 2092 2093 dprintk("RPC: worker connecting xprt %p via %s to " 2094 "%s (port %s)\n", xprt, 2095 xprt->address_strings[RPC_DISPLAY_PROTO], 2096 xprt->address_strings[RPC_DISPLAY_ADDR], 2097 xprt->address_strings[RPC_DISPLAY_PORT]); 2098 2099 xs_udp_finish_connecting(xprt, sock); 2100 trace_rpc_socket_connect(xprt, sock, 0); 2101 status = 0; 2102 out: 2103 xprt_unlock_connect(xprt, transport); 2104 xprt_clear_connecting(xprt); 2105 xprt_wake_pending_tasks(xprt, status); 2106 } 2107 2108 /** 2109 * xs_tcp_shutdown - gracefully shut down a TCP socket 2110 * @xprt: transport 2111 * 2112 * Initiates a graceful shutdown of the TCP socket by calling the 2113 * equivalent of shutdown(SHUT_RDWR); 2114 */ 2115 static void xs_tcp_shutdown(struct rpc_xprt *xprt) 2116 { 2117 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); 2118 struct socket *sock = transport->sock; 2119 2120 if (sock == NULL) 2121 return; 2122 if (xprt_connected(xprt)) { 2123 kernel_sock_shutdown(sock, SHUT_RDWR); 2124 trace_rpc_socket_shutdown(xprt, sock); 2125 } else 2126 xs_reset_transport(transport); 2127 } 2128 2129 static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock) 2130 { 2131 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); 2132 int ret = -ENOTCONN; 2133 2134 if (!transport->inet) { 2135 struct sock *sk = sock->sk; 2136 unsigned int keepidle = xprt->timeout->to_initval / HZ; 2137 unsigned int keepcnt = xprt->timeout->to_retries + 1; 2138 unsigned int opt_on = 1; 2139 unsigned int timeo; 2140 2141 /* TCP Keepalive options */ 2142 kernel_setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE, 2143 (char *)&opt_on, sizeof(opt_on)); 2144 kernel_setsockopt(sock, SOL_TCP, TCP_KEEPIDLE, 2145 (char *)&keepidle, sizeof(keepidle)); 2146 kernel_setsockopt(sock, SOL_TCP, TCP_KEEPINTVL, 2147 (char *)&keepidle, sizeof(keepidle)); 2148 kernel_setsockopt(sock, SOL_TCP, TCP_KEEPCNT, 2149 (char *)&keepcnt, sizeof(keepcnt)); 2150 2151 /* TCP user timeout (see RFC5482) */ 2152 timeo = jiffies_to_msecs(xprt->timeout->to_initval) * 2153 (xprt->timeout->to_retries + 1); 2154 kernel_setsockopt(sock, SOL_TCP, TCP_USER_TIMEOUT, 2155 (char *)&timeo, sizeof(timeo)); 2156 2157 write_lock_bh(&sk->sk_callback_lock); 2158 2159 xs_save_old_callbacks(transport, sk); 2160 2161 sk->sk_user_data = xprt; 2162 sk->sk_data_ready = xs_tcp_data_ready; 2163 sk->sk_state_change = xs_tcp_state_change; 2164 sk->sk_write_space = xs_tcp_write_space; 2165 sk->sk_error_report = xs_error_report; 2166 sk->sk_allocation = GFP_NOIO; 2167 2168 /* socket options */ 2169 sock_reset_flag(sk, SOCK_LINGER); 2170 tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF; 2171 2172 xprt_clear_connected(xprt); 2173 2174 /* Reset to new socket */ 2175 transport->sock = sock; 2176 transport->inet = sk; 2177 2178 write_unlock_bh(&sk->sk_callback_lock); 2179 } 2180 2181 if (!xprt_bound(xprt)) 2182 goto out; 2183 2184 xs_set_memalloc(xprt); 2185 2186 /* Tell the socket layer to start connecting... */ 2187 xprt->stat.connect_count++; 2188 xprt->stat.connect_start = jiffies; 2189 set_bit(XPRT_SOCK_CONNECTING, &transport->sock_state); 2190 ret = kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK); 2191 switch (ret) { 2192 case 0: 2193 xs_set_srcport(transport, sock); 2194 case -EINPROGRESS: 2195 /* SYN_SENT! */ 2196 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO) 2197 xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO; 2198 } 2199 out: 2200 return ret; 2201 } 2202 2203 /** 2204 * xs_tcp_setup_socket - create a TCP socket and connect to a remote endpoint 2205 * 2206 * Invoked by a work queue tasklet. 2207 */ 2208 static void xs_tcp_setup_socket(struct work_struct *work) 2209 { 2210 struct sock_xprt *transport = 2211 container_of(work, struct sock_xprt, connect_worker.work); 2212 struct socket *sock = transport->sock; 2213 struct rpc_xprt *xprt = &transport->xprt; 2214 int status = -EIO; 2215 2216 if (!sock) { 2217 sock = xs_create_sock(xprt, transport, 2218 xs_addr(xprt)->sa_family, SOCK_STREAM, 2219 IPPROTO_TCP, true); 2220 if (IS_ERR(sock)) { 2221 status = PTR_ERR(sock); 2222 goto out; 2223 } 2224 } 2225 2226 dprintk("RPC: worker connecting xprt %p via %s to " 2227 "%s (port %s)\n", xprt, 2228 xprt->address_strings[RPC_DISPLAY_PROTO], 2229 xprt->address_strings[RPC_DISPLAY_ADDR], 2230 xprt->address_strings[RPC_DISPLAY_PORT]); 2231 2232 status = xs_tcp_finish_connecting(xprt, sock); 2233 trace_rpc_socket_connect(xprt, sock, status); 2234 dprintk("RPC: %p connect status %d connected %d sock state %d\n", 2235 xprt, -status, xprt_connected(xprt), 2236 sock->sk->sk_state); 2237 switch (status) { 2238 default: 2239 printk("%s: connect returned unhandled error %d\n", 2240 __func__, status); 2241 case -EADDRNOTAVAIL: 2242 /* We're probably in TIME_WAIT. Get rid of existing socket, 2243 * and retry 2244 */ 2245 xs_tcp_force_close(xprt); 2246 break; 2247 case 0: 2248 case -EINPROGRESS: 2249 case -EALREADY: 2250 xprt_unlock_connect(xprt, transport); 2251 return; 2252 case -EINVAL: 2253 /* Happens, for instance, if the user specified a link 2254 * local IPv6 address without a scope-id. 2255 */ 2256 case -ECONNREFUSED: 2257 case -ECONNRESET: 2258 case -ENETUNREACH: 2259 case -EADDRINUSE: 2260 case -ENOBUFS: 2261 /* retry with existing socket, after a delay */ 2262 xs_tcp_force_close(xprt); 2263 goto out; 2264 } 2265 status = -EAGAIN; 2266 out: 2267 xprt_unlock_connect(xprt, transport); 2268 xprt_clear_connecting(xprt); 2269 xprt_wake_pending_tasks(xprt, status); 2270 } 2271 2272 /** 2273 * xs_connect - connect a socket to a remote endpoint 2274 * @xprt: pointer to transport structure 2275 * @task: address of RPC task that manages state of connect request 2276 * 2277 * TCP: If the remote end dropped the connection, delay reconnecting. 2278 * 2279 * UDP socket connects are synchronous, but we use a work queue anyway 2280 * to guarantee that even unprivileged user processes can set up a 2281 * socket on a privileged port. 2282 * 2283 * If a UDP socket connect fails, the delay behavior here prevents 2284 * retry floods (hard mounts). 2285 */ 2286 static void xs_connect(struct rpc_xprt *xprt, struct rpc_task *task) 2287 { 2288 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); 2289 2290 WARN_ON_ONCE(!xprt_lock_connect(xprt, task, transport)); 2291 2292 if (transport->sock != NULL) { 2293 dprintk("RPC: xs_connect delayed xprt %p for %lu " 2294 "seconds\n", 2295 xprt, xprt->reestablish_timeout / HZ); 2296 2297 /* Start by resetting any existing state */ 2298 xs_reset_transport(transport); 2299 2300 queue_delayed_work(rpciod_workqueue, 2301 &transport->connect_worker, 2302 xprt->reestablish_timeout); 2303 xprt->reestablish_timeout <<= 1; 2304 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO) 2305 xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO; 2306 if (xprt->reestablish_timeout > XS_TCP_MAX_REEST_TO) 2307 xprt->reestablish_timeout = XS_TCP_MAX_REEST_TO; 2308 } else { 2309 dprintk("RPC: xs_connect scheduled xprt %p\n", xprt); 2310 queue_delayed_work(rpciod_workqueue, 2311 &transport->connect_worker, 0); 2312 } 2313 } 2314 2315 /** 2316 * xs_local_print_stats - display AF_LOCAL socket-specifc stats 2317 * @xprt: rpc_xprt struct containing statistics 2318 * @seq: output file 2319 * 2320 */ 2321 static void xs_local_print_stats(struct rpc_xprt *xprt, struct seq_file *seq) 2322 { 2323 long idle_time = 0; 2324 2325 if (xprt_connected(xprt)) 2326 idle_time = (long)(jiffies - xprt->last_used) / HZ; 2327 2328 seq_printf(seq, "\txprt:\tlocal %lu %lu %lu %ld %lu %lu %lu " 2329 "%llu %llu %lu %llu %llu\n", 2330 xprt->stat.bind_count, 2331 xprt->stat.connect_count, 2332 xprt->stat.connect_time, 2333 idle_time, 2334 xprt->stat.sends, 2335 xprt->stat.recvs, 2336 xprt->stat.bad_xids, 2337 xprt->stat.req_u, 2338 xprt->stat.bklog_u, 2339 xprt->stat.max_slots, 2340 xprt->stat.sending_u, 2341 xprt->stat.pending_u); 2342 } 2343 2344 /** 2345 * xs_udp_print_stats - display UDP socket-specifc stats 2346 * @xprt: rpc_xprt struct containing statistics 2347 * @seq: output file 2348 * 2349 */ 2350 static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq) 2351 { 2352 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); 2353 2354 seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %llu %llu " 2355 "%lu %llu %llu\n", 2356 transport->srcport, 2357 xprt->stat.bind_count, 2358 xprt->stat.sends, 2359 xprt->stat.recvs, 2360 xprt->stat.bad_xids, 2361 xprt->stat.req_u, 2362 xprt->stat.bklog_u, 2363 xprt->stat.max_slots, 2364 xprt->stat.sending_u, 2365 xprt->stat.pending_u); 2366 } 2367 2368 /** 2369 * xs_tcp_print_stats - display TCP socket-specifc stats 2370 * @xprt: rpc_xprt struct containing statistics 2371 * @seq: output file 2372 * 2373 */ 2374 static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq) 2375 { 2376 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); 2377 long idle_time = 0; 2378 2379 if (xprt_connected(xprt)) 2380 idle_time = (long)(jiffies - xprt->last_used) / HZ; 2381 2382 seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu " 2383 "%llu %llu %lu %llu %llu\n", 2384 transport->srcport, 2385 xprt->stat.bind_count, 2386 xprt->stat.connect_count, 2387 xprt->stat.connect_time, 2388 idle_time, 2389 xprt->stat.sends, 2390 xprt->stat.recvs, 2391 xprt->stat.bad_xids, 2392 xprt->stat.req_u, 2393 xprt->stat.bklog_u, 2394 xprt->stat.max_slots, 2395 xprt->stat.sending_u, 2396 xprt->stat.pending_u); 2397 } 2398 2399 /* 2400 * Allocate a bunch of pages for a scratch buffer for the rpc code. The reason 2401 * we allocate pages instead doing a kmalloc like rpc_malloc is because we want 2402 * to use the server side send routines. 2403 */ 2404 static void *bc_malloc(struct rpc_task *task, size_t size) 2405 { 2406 struct page *page; 2407 struct rpc_buffer *buf; 2408 2409 WARN_ON_ONCE(size > PAGE_SIZE - sizeof(struct rpc_buffer)); 2410 if (size > PAGE_SIZE - sizeof(struct rpc_buffer)) 2411 return NULL; 2412 2413 page = alloc_page(GFP_KERNEL); 2414 if (!page) 2415 return NULL; 2416 2417 buf = page_address(page); 2418 buf->len = PAGE_SIZE; 2419 2420 return buf->data; 2421 } 2422 2423 /* 2424 * Free the space allocated in the bc_alloc routine 2425 */ 2426 static void bc_free(void *buffer) 2427 { 2428 struct rpc_buffer *buf; 2429 2430 if (!buffer) 2431 return; 2432 2433 buf = container_of(buffer, struct rpc_buffer, data); 2434 free_page((unsigned long)buf); 2435 } 2436 2437 /* 2438 * Use the svc_sock to send the callback. Must be called with svsk->sk_mutex 2439 * held. Borrows heavily from svc_tcp_sendto and xs_tcp_send_request. 2440 */ 2441 static int bc_sendto(struct rpc_rqst *req) 2442 { 2443 int len; 2444 struct xdr_buf *xbufp = &req->rq_snd_buf; 2445 struct rpc_xprt *xprt = req->rq_xprt; 2446 struct sock_xprt *transport = 2447 container_of(xprt, struct sock_xprt, xprt); 2448 struct socket *sock = transport->sock; 2449 unsigned long headoff; 2450 unsigned long tailoff; 2451 2452 xs_encode_stream_record_marker(xbufp); 2453 2454 tailoff = (unsigned long)xbufp->tail[0].iov_base & ~PAGE_MASK; 2455 headoff = (unsigned long)xbufp->head[0].iov_base & ~PAGE_MASK; 2456 len = svc_send_common(sock, xbufp, 2457 virt_to_page(xbufp->head[0].iov_base), headoff, 2458 xbufp->tail[0].iov_base, tailoff); 2459 2460 if (len != xbufp->len) { 2461 printk(KERN_NOTICE "Error sending entire callback!\n"); 2462 len = -EAGAIN; 2463 } 2464 2465 return len; 2466 } 2467 2468 /* 2469 * The send routine. Borrows from svc_send 2470 */ 2471 static int bc_send_request(struct rpc_task *task) 2472 { 2473 struct rpc_rqst *req = task->tk_rqstp; 2474 struct svc_xprt *xprt; 2475 u32 len; 2476 2477 dprintk("sending request with xid: %08x\n", ntohl(req->rq_xid)); 2478 /* 2479 * Get the server socket associated with this callback xprt 2480 */ 2481 xprt = req->rq_xprt->bc_xprt; 2482 2483 /* 2484 * Grab the mutex to serialize data as the connection is shared 2485 * with the fore channel 2486 */ 2487 if (!mutex_trylock(&xprt->xpt_mutex)) { 2488 rpc_sleep_on(&xprt->xpt_bc_pending, task, NULL); 2489 if (!mutex_trylock(&xprt->xpt_mutex)) 2490 return -EAGAIN; 2491 rpc_wake_up_queued_task(&xprt->xpt_bc_pending, task); 2492 } 2493 if (test_bit(XPT_DEAD, &xprt->xpt_flags)) 2494 len = -ENOTCONN; 2495 else 2496 len = bc_sendto(req); 2497 mutex_unlock(&xprt->xpt_mutex); 2498 2499 if (len > 0) 2500 len = 0; 2501 2502 return len; 2503 } 2504 2505 /* 2506 * The close routine. Since this is client initiated, we do nothing 2507 */ 2508 2509 static void bc_close(struct rpc_xprt *xprt) 2510 { 2511 } 2512 2513 /* 2514 * The xprt destroy routine. Again, because this connection is client 2515 * initiated, we do nothing 2516 */ 2517 2518 static void bc_destroy(struct rpc_xprt *xprt) 2519 { 2520 dprintk("RPC: bc_destroy xprt %p\n", xprt); 2521 2522 xs_xprt_free(xprt); 2523 module_put(THIS_MODULE); 2524 } 2525 2526 static struct rpc_xprt_ops xs_local_ops = { 2527 .reserve_xprt = xprt_reserve_xprt, 2528 .release_xprt = xs_tcp_release_xprt, 2529 .alloc_slot = xprt_alloc_slot, 2530 .rpcbind = xs_local_rpcbind, 2531 .set_port = xs_local_set_port, 2532 .connect = xs_local_connect, 2533 .buf_alloc = rpc_malloc, 2534 .buf_free = rpc_free, 2535 .send_request = xs_local_send_request, 2536 .set_retrans_timeout = xprt_set_retrans_timeout_def, 2537 .close = xs_close, 2538 .destroy = xs_destroy, 2539 .print_stats = xs_local_print_stats, 2540 .enable_swap = xs_enable_swap, 2541 .disable_swap = xs_disable_swap, 2542 }; 2543 2544 static struct rpc_xprt_ops xs_udp_ops = { 2545 .set_buffer_size = xs_udp_set_buffer_size, 2546 .reserve_xprt = xprt_reserve_xprt_cong, 2547 .release_xprt = xprt_release_xprt_cong, 2548 .alloc_slot = xprt_alloc_slot, 2549 .rpcbind = rpcb_getport_async, 2550 .set_port = xs_set_port, 2551 .connect = xs_connect, 2552 .buf_alloc = rpc_malloc, 2553 .buf_free = rpc_free, 2554 .send_request = xs_udp_send_request, 2555 .set_retrans_timeout = xprt_set_retrans_timeout_rtt, 2556 .timer = xs_udp_timer, 2557 .release_request = xprt_release_rqst_cong, 2558 .close = xs_close, 2559 .destroy = xs_destroy, 2560 .print_stats = xs_udp_print_stats, 2561 .enable_swap = xs_enable_swap, 2562 .disable_swap = xs_disable_swap, 2563 .inject_disconnect = xs_inject_disconnect, 2564 }; 2565 2566 static struct rpc_xprt_ops xs_tcp_ops = { 2567 .reserve_xprt = xprt_reserve_xprt, 2568 .release_xprt = xs_tcp_release_xprt, 2569 .alloc_slot = xprt_lock_and_alloc_slot, 2570 .rpcbind = rpcb_getport_async, 2571 .set_port = xs_set_port, 2572 .connect = xs_connect, 2573 .buf_alloc = rpc_malloc, 2574 .buf_free = rpc_free, 2575 .send_request = xs_tcp_send_request, 2576 .set_retrans_timeout = xprt_set_retrans_timeout_def, 2577 .close = xs_tcp_shutdown, 2578 .destroy = xs_destroy, 2579 .print_stats = xs_tcp_print_stats, 2580 .enable_swap = xs_enable_swap, 2581 .disable_swap = xs_disable_swap, 2582 .inject_disconnect = xs_inject_disconnect, 2583 }; 2584 2585 /* 2586 * The rpc_xprt_ops for the server backchannel 2587 */ 2588 2589 static struct rpc_xprt_ops bc_tcp_ops = { 2590 .reserve_xprt = xprt_reserve_xprt, 2591 .release_xprt = xprt_release_xprt, 2592 .alloc_slot = xprt_alloc_slot, 2593 .buf_alloc = bc_malloc, 2594 .buf_free = bc_free, 2595 .send_request = bc_send_request, 2596 .set_retrans_timeout = xprt_set_retrans_timeout_def, 2597 .close = bc_close, 2598 .destroy = bc_destroy, 2599 .print_stats = xs_tcp_print_stats, 2600 .enable_swap = xs_enable_swap, 2601 .disable_swap = xs_disable_swap, 2602 .inject_disconnect = xs_inject_disconnect, 2603 }; 2604 2605 static int xs_init_anyaddr(const int family, struct sockaddr *sap) 2606 { 2607 static const struct sockaddr_in sin = { 2608 .sin_family = AF_INET, 2609 .sin_addr.s_addr = htonl(INADDR_ANY), 2610 }; 2611 static const struct sockaddr_in6 sin6 = { 2612 .sin6_family = AF_INET6, 2613 .sin6_addr = IN6ADDR_ANY_INIT, 2614 }; 2615 2616 switch (family) { 2617 case AF_LOCAL: 2618 break; 2619 case AF_INET: 2620 memcpy(sap, &sin, sizeof(sin)); 2621 break; 2622 case AF_INET6: 2623 memcpy(sap, &sin6, sizeof(sin6)); 2624 break; 2625 default: 2626 dprintk("RPC: %s: Bad address family\n", __func__); 2627 return -EAFNOSUPPORT; 2628 } 2629 return 0; 2630 } 2631 2632 static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args, 2633 unsigned int slot_table_size, 2634 unsigned int max_slot_table_size) 2635 { 2636 struct rpc_xprt *xprt; 2637 struct sock_xprt *new; 2638 2639 if (args->addrlen > sizeof(xprt->addr)) { 2640 dprintk("RPC: xs_setup_xprt: address too large\n"); 2641 return ERR_PTR(-EBADF); 2642 } 2643 2644 xprt = xprt_alloc(args->net, sizeof(*new), slot_table_size, 2645 max_slot_table_size); 2646 if (xprt == NULL) { 2647 dprintk("RPC: xs_setup_xprt: couldn't allocate " 2648 "rpc_xprt\n"); 2649 return ERR_PTR(-ENOMEM); 2650 } 2651 2652 new = container_of(xprt, struct sock_xprt, xprt); 2653 memcpy(&xprt->addr, args->dstaddr, args->addrlen); 2654 xprt->addrlen = args->addrlen; 2655 if (args->srcaddr) 2656 memcpy(&new->srcaddr, args->srcaddr, args->addrlen); 2657 else { 2658 int err; 2659 err = xs_init_anyaddr(args->dstaddr->sa_family, 2660 (struct sockaddr *)&new->srcaddr); 2661 if (err != 0) { 2662 xprt_free(xprt); 2663 return ERR_PTR(err); 2664 } 2665 } 2666 2667 return xprt; 2668 } 2669 2670 static const struct rpc_timeout xs_local_default_timeout = { 2671 .to_initval = 10 * HZ, 2672 .to_maxval = 10 * HZ, 2673 .to_retries = 2, 2674 }; 2675 2676 /** 2677 * xs_setup_local - Set up transport to use an AF_LOCAL socket 2678 * @args: rpc transport creation arguments 2679 * 2680 * AF_LOCAL is a "tpi_cots_ord" transport, just like TCP 2681 */ 2682 static struct rpc_xprt *xs_setup_local(struct xprt_create *args) 2683 { 2684 struct sockaddr_un *sun = (struct sockaddr_un *)args->dstaddr; 2685 struct sock_xprt *transport; 2686 struct rpc_xprt *xprt; 2687 struct rpc_xprt *ret; 2688 2689 xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries, 2690 xprt_max_tcp_slot_table_entries); 2691 if (IS_ERR(xprt)) 2692 return xprt; 2693 transport = container_of(xprt, struct sock_xprt, xprt); 2694 2695 xprt->prot = 0; 2696 xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32); 2697 xprt->max_payload = RPC_MAX_FRAGMENT_SIZE; 2698 2699 xprt->bind_timeout = XS_BIND_TO; 2700 xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO; 2701 xprt->idle_timeout = XS_IDLE_DISC_TO; 2702 2703 xprt->ops = &xs_local_ops; 2704 xprt->timeout = &xs_local_default_timeout; 2705 2706 INIT_DELAYED_WORK(&transport->connect_worker, 2707 xs_dummy_setup_socket); 2708 2709 switch (sun->sun_family) { 2710 case AF_LOCAL: 2711 if (sun->sun_path[0] != '/') { 2712 dprintk("RPC: bad AF_LOCAL address: %s\n", 2713 sun->sun_path); 2714 ret = ERR_PTR(-EINVAL); 2715 goto out_err; 2716 } 2717 xprt_set_bound(xprt); 2718 xs_format_peer_addresses(xprt, "local", RPCBIND_NETID_LOCAL); 2719 ret = ERR_PTR(xs_local_setup_socket(transport)); 2720 if (ret) 2721 goto out_err; 2722 break; 2723 default: 2724 ret = ERR_PTR(-EAFNOSUPPORT); 2725 goto out_err; 2726 } 2727 2728 dprintk("RPC: set up xprt to %s via AF_LOCAL\n", 2729 xprt->address_strings[RPC_DISPLAY_ADDR]); 2730 2731 if (try_module_get(THIS_MODULE)) 2732 return xprt; 2733 ret = ERR_PTR(-EINVAL); 2734 out_err: 2735 xs_xprt_free(xprt); 2736 return ret; 2737 } 2738 2739 static const struct rpc_timeout xs_udp_default_timeout = { 2740 .to_initval = 5 * HZ, 2741 .to_maxval = 30 * HZ, 2742 .to_increment = 5 * HZ, 2743 .to_retries = 5, 2744 }; 2745 2746 /** 2747 * xs_setup_udp - Set up transport to use a UDP socket 2748 * @args: rpc transport creation arguments 2749 * 2750 */ 2751 static struct rpc_xprt *xs_setup_udp(struct xprt_create *args) 2752 { 2753 struct sockaddr *addr = args->dstaddr; 2754 struct rpc_xprt *xprt; 2755 struct sock_xprt *transport; 2756 struct rpc_xprt *ret; 2757 2758 xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries, 2759 xprt_udp_slot_table_entries); 2760 if (IS_ERR(xprt)) 2761 return xprt; 2762 transport = container_of(xprt, struct sock_xprt, xprt); 2763 2764 xprt->prot = IPPROTO_UDP; 2765 xprt->tsh_size = 0; 2766 /* XXX: header size can vary due to auth type, IPv6, etc. */ 2767 xprt->max_payload = (1U << 16) - (MAX_HEADER << 3); 2768 2769 xprt->bind_timeout = XS_BIND_TO; 2770 xprt->reestablish_timeout = XS_UDP_REEST_TO; 2771 xprt->idle_timeout = XS_IDLE_DISC_TO; 2772 2773 xprt->ops = &xs_udp_ops; 2774 2775 xprt->timeout = &xs_udp_default_timeout; 2776 2777 switch (addr->sa_family) { 2778 case AF_INET: 2779 if (((struct sockaddr_in *)addr)->sin_port != htons(0)) 2780 xprt_set_bound(xprt); 2781 2782 INIT_DELAYED_WORK(&transport->connect_worker, 2783 xs_udp_setup_socket); 2784 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP); 2785 break; 2786 case AF_INET6: 2787 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0)) 2788 xprt_set_bound(xprt); 2789 2790 INIT_DELAYED_WORK(&transport->connect_worker, 2791 xs_udp_setup_socket); 2792 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP6); 2793 break; 2794 default: 2795 ret = ERR_PTR(-EAFNOSUPPORT); 2796 goto out_err; 2797 } 2798 2799 if (xprt_bound(xprt)) 2800 dprintk("RPC: set up xprt to %s (port %s) via %s\n", 2801 xprt->address_strings[RPC_DISPLAY_ADDR], 2802 xprt->address_strings[RPC_DISPLAY_PORT], 2803 xprt->address_strings[RPC_DISPLAY_PROTO]); 2804 else 2805 dprintk("RPC: set up xprt to %s (autobind) via %s\n", 2806 xprt->address_strings[RPC_DISPLAY_ADDR], 2807 xprt->address_strings[RPC_DISPLAY_PROTO]); 2808 2809 if (try_module_get(THIS_MODULE)) 2810 return xprt; 2811 ret = ERR_PTR(-EINVAL); 2812 out_err: 2813 xs_xprt_free(xprt); 2814 return ret; 2815 } 2816 2817 static const struct rpc_timeout xs_tcp_default_timeout = { 2818 .to_initval = 60 * HZ, 2819 .to_maxval = 60 * HZ, 2820 .to_retries = 2, 2821 }; 2822 2823 /** 2824 * xs_setup_tcp - Set up transport to use a TCP socket 2825 * @args: rpc transport creation arguments 2826 * 2827 */ 2828 static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args) 2829 { 2830 struct sockaddr *addr = args->dstaddr; 2831 struct rpc_xprt *xprt; 2832 struct sock_xprt *transport; 2833 struct rpc_xprt *ret; 2834 unsigned int max_slot_table_size = xprt_max_tcp_slot_table_entries; 2835 2836 if (args->flags & XPRT_CREATE_INFINITE_SLOTS) 2837 max_slot_table_size = RPC_MAX_SLOT_TABLE_LIMIT; 2838 2839 xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries, 2840 max_slot_table_size); 2841 if (IS_ERR(xprt)) 2842 return xprt; 2843 transport = container_of(xprt, struct sock_xprt, xprt); 2844 2845 xprt->prot = IPPROTO_TCP; 2846 xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32); 2847 xprt->max_payload = RPC_MAX_FRAGMENT_SIZE; 2848 2849 xprt->bind_timeout = XS_BIND_TO; 2850 xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO; 2851 xprt->idle_timeout = XS_IDLE_DISC_TO; 2852 2853 xprt->ops = &xs_tcp_ops; 2854 xprt->timeout = &xs_tcp_default_timeout; 2855 2856 switch (addr->sa_family) { 2857 case AF_INET: 2858 if (((struct sockaddr_in *)addr)->sin_port != htons(0)) 2859 xprt_set_bound(xprt); 2860 2861 INIT_DELAYED_WORK(&transport->connect_worker, 2862 xs_tcp_setup_socket); 2863 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP); 2864 break; 2865 case AF_INET6: 2866 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0)) 2867 xprt_set_bound(xprt); 2868 2869 INIT_DELAYED_WORK(&transport->connect_worker, 2870 xs_tcp_setup_socket); 2871 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6); 2872 break; 2873 default: 2874 ret = ERR_PTR(-EAFNOSUPPORT); 2875 goto out_err; 2876 } 2877 2878 if (xprt_bound(xprt)) 2879 dprintk("RPC: set up xprt to %s (port %s) via %s\n", 2880 xprt->address_strings[RPC_DISPLAY_ADDR], 2881 xprt->address_strings[RPC_DISPLAY_PORT], 2882 xprt->address_strings[RPC_DISPLAY_PROTO]); 2883 else 2884 dprintk("RPC: set up xprt to %s (autobind) via %s\n", 2885 xprt->address_strings[RPC_DISPLAY_ADDR], 2886 xprt->address_strings[RPC_DISPLAY_PROTO]); 2887 2888 if (try_module_get(THIS_MODULE)) 2889 return xprt; 2890 ret = ERR_PTR(-EINVAL); 2891 out_err: 2892 xs_xprt_free(xprt); 2893 return ret; 2894 } 2895 2896 /** 2897 * xs_setup_bc_tcp - Set up transport to use a TCP backchannel socket 2898 * @args: rpc transport creation arguments 2899 * 2900 */ 2901 static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args) 2902 { 2903 struct sockaddr *addr = args->dstaddr; 2904 struct rpc_xprt *xprt; 2905 struct sock_xprt *transport; 2906 struct svc_sock *bc_sock; 2907 struct rpc_xprt *ret; 2908 2909 xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries, 2910 xprt_tcp_slot_table_entries); 2911 if (IS_ERR(xprt)) 2912 return xprt; 2913 transport = container_of(xprt, struct sock_xprt, xprt); 2914 2915 xprt->prot = IPPROTO_TCP; 2916 xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32); 2917 xprt->max_payload = RPC_MAX_FRAGMENT_SIZE; 2918 xprt->timeout = &xs_tcp_default_timeout; 2919 2920 /* backchannel */ 2921 xprt_set_bound(xprt); 2922 xprt->bind_timeout = 0; 2923 xprt->reestablish_timeout = 0; 2924 xprt->idle_timeout = 0; 2925 2926 xprt->ops = &bc_tcp_ops; 2927 2928 switch (addr->sa_family) { 2929 case AF_INET: 2930 xs_format_peer_addresses(xprt, "tcp", 2931 RPCBIND_NETID_TCP); 2932 break; 2933 case AF_INET6: 2934 xs_format_peer_addresses(xprt, "tcp", 2935 RPCBIND_NETID_TCP6); 2936 break; 2937 default: 2938 ret = ERR_PTR(-EAFNOSUPPORT); 2939 goto out_err; 2940 } 2941 2942 dprintk("RPC: set up xprt to %s (port %s) via %s\n", 2943 xprt->address_strings[RPC_DISPLAY_ADDR], 2944 xprt->address_strings[RPC_DISPLAY_PORT], 2945 xprt->address_strings[RPC_DISPLAY_PROTO]); 2946 2947 /* 2948 * Once we've associated a backchannel xprt with a connection, 2949 * we want to keep it around as long as the connection lasts, 2950 * in case we need to start using it for a backchannel again; 2951 * this reference won't be dropped until bc_xprt is destroyed. 2952 */ 2953 xprt_get(xprt); 2954 args->bc_xprt->xpt_bc_xprt = xprt; 2955 xprt->bc_xprt = args->bc_xprt; 2956 bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt); 2957 transport->sock = bc_sock->sk_sock; 2958 transport->inet = bc_sock->sk_sk; 2959 2960 /* 2961 * Since we don't want connections for the backchannel, we set 2962 * the xprt status to connected 2963 */ 2964 xprt_set_connected(xprt); 2965 2966 if (try_module_get(THIS_MODULE)) 2967 return xprt; 2968 2969 args->bc_xprt->xpt_bc_xprt = NULL; 2970 xprt_put(xprt); 2971 ret = ERR_PTR(-EINVAL); 2972 out_err: 2973 xs_xprt_free(xprt); 2974 return ret; 2975 } 2976 2977 static struct xprt_class xs_local_transport = { 2978 .list = LIST_HEAD_INIT(xs_local_transport.list), 2979 .name = "named UNIX socket", 2980 .owner = THIS_MODULE, 2981 .ident = XPRT_TRANSPORT_LOCAL, 2982 .setup = xs_setup_local, 2983 }; 2984 2985 static struct xprt_class xs_udp_transport = { 2986 .list = LIST_HEAD_INIT(xs_udp_transport.list), 2987 .name = "udp", 2988 .owner = THIS_MODULE, 2989 .ident = XPRT_TRANSPORT_UDP, 2990 .setup = xs_setup_udp, 2991 }; 2992 2993 static struct xprt_class xs_tcp_transport = { 2994 .list = LIST_HEAD_INIT(xs_tcp_transport.list), 2995 .name = "tcp", 2996 .owner = THIS_MODULE, 2997 .ident = XPRT_TRANSPORT_TCP, 2998 .setup = xs_setup_tcp, 2999 }; 3000 3001 static struct xprt_class xs_bc_tcp_transport = { 3002 .list = LIST_HEAD_INIT(xs_bc_tcp_transport.list), 3003 .name = "tcp NFSv4.1 backchannel", 3004 .owner = THIS_MODULE, 3005 .ident = XPRT_TRANSPORT_BC_TCP, 3006 .setup = xs_setup_bc_tcp, 3007 }; 3008 3009 /** 3010 * init_socket_xprt - set up xprtsock's sysctls, register with RPC client 3011 * 3012 */ 3013 int init_socket_xprt(void) 3014 { 3015 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 3016 if (!sunrpc_table_header) 3017 sunrpc_table_header = register_sysctl_table(sunrpc_table); 3018 #endif 3019 3020 xprt_register_transport(&xs_local_transport); 3021 xprt_register_transport(&xs_udp_transport); 3022 xprt_register_transport(&xs_tcp_transport); 3023 xprt_register_transport(&xs_bc_tcp_transport); 3024 3025 return 0; 3026 } 3027 3028 /** 3029 * cleanup_socket_xprt - remove xprtsock's sysctls, unregister 3030 * 3031 */ 3032 void cleanup_socket_xprt(void) 3033 { 3034 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 3035 if (sunrpc_table_header) { 3036 unregister_sysctl_table(sunrpc_table_header); 3037 sunrpc_table_header = NULL; 3038 } 3039 #endif 3040 3041 xprt_unregister_transport(&xs_local_transport); 3042 xprt_unregister_transport(&xs_udp_transport); 3043 xprt_unregister_transport(&xs_tcp_transport); 3044 xprt_unregister_transport(&xs_bc_tcp_transport); 3045 } 3046 3047 static int param_set_uint_minmax(const char *val, 3048 const struct kernel_param *kp, 3049 unsigned int min, unsigned int max) 3050 { 3051 unsigned int num; 3052 int ret; 3053 3054 if (!val) 3055 return -EINVAL; 3056 ret = kstrtouint(val, 0, &num); 3057 if (ret == -EINVAL || num < min || num > max) 3058 return -EINVAL; 3059 *((unsigned int *)kp->arg) = num; 3060 return 0; 3061 } 3062 3063 static int param_set_portnr(const char *val, const struct kernel_param *kp) 3064 { 3065 return param_set_uint_minmax(val, kp, 3066 RPC_MIN_RESVPORT, 3067 RPC_MAX_RESVPORT); 3068 } 3069 3070 static const struct kernel_param_ops param_ops_portnr = { 3071 .set = param_set_portnr, 3072 .get = param_get_uint, 3073 }; 3074 3075 #define param_check_portnr(name, p) \ 3076 __param_check(name, p, unsigned int); 3077 3078 module_param_named(min_resvport, xprt_min_resvport, portnr, 0644); 3079 module_param_named(max_resvport, xprt_max_resvport, portnr, 0644); 3080 3081 static int param_set_slot_table_size(const char *val, 3082 const struct kernel_param *kp) 3083 { 3084 return param_set_uint_minmax(val, kp, 3085 RPC_MIN_SLOT_TABLE, 3086 RPC_MAX_SLOT_TABLE); 3087 } 3088 3089 static const struct kernel_param_ops param_ops_slot_table_size = { 3090 .set = param_set_slot_table_size, 3091 .get = param_get_uint, 3092 }; 3093 3094 #define param_check_slot_table_size(name, p) \ 3095 __param_check(name, p, unsigned int); 3096 3097 static int param_set_max_slot_table_size(const char *val, 3098 const struct kernel_param *kp) 3099 { 3100 return param_set_uint_minmax(val, kp, 3101 RPC_MIN_SLOT_TABLE, 3102 RPC_MAX_SLOT_TABLE_LIMIT); 3103 } 3104 3105 static const struct kernel_param_ops param_ops_max_slot_table_size = { 3106 .set = param_set_max_slot_table_size, 3107 .get = param_get_uint, 3108 }; 3109 3110 #define param_check_max_slot_table_size(name, p) \ 3111 __param_check(name, p, unsigned int); 3112 3113 module_param_named(tcp_slot_table_entries, xprt_tcp_slot_table_entries, 3114 slot_table_size, 0644); 3115 module_param_named(tcp_max_slot_table_entries, xprt_max_tcp_slot_table_entries, 3116 max_slot_table_size, 0644); 3117 module_param_named(udp_slot_table_entries, xprt_udp_slot_table_entries, 3118 slot_table_size, 0644); 3119 3120