1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * linux/net/sunrpc/xprtsock.c 4 * 5 * Client-side transport implementation for sockets. 6 * 7 * TCP callback races fixes (C) 1998 Red Hat 8 * TCP send fixes (C) 1998 Red Hat 9 * TCP NFS related read + write fixes 10 * (C) 1999 Dave Airlie, University of Limerick, Ireland <airlied@linux.ie> 11 * 12 * Rewrite of larges part of the code in order to stabilize TCP stuff. 13 * Fix behaviour when socket buffer is full. 14 * (C) 1999 Trond Myklebust <trond.myklebust@fys.uio.no> 15 * 16 * IP socket transport implementation, (C) 2005 Chuck Lever <cel@netapp.com> 17 * 18 * IPv6 support contributed by Gilles Quillard, Bull Open Source, 2005. 19 * <gilles.quillard@bull.net> 20 */ 21 22 #include <linux/types.h> 23 #include <linux/string.h> 24 #include <linux/slab.h> 25 #include <linux/module.h> 26 #include <linux/capability.h> 27 #include <linux/pagemap.h> 28 #include <linux/errno.h> 29 #include <linux/socket.h> 30 #include <linux/in.h> 31 #include <linux/net.h> 32 #include <linux/mm.h> 33 #include <linux/un.h> 34 #include <linux/udp.h> 35 #include <linux/tcp.h> 36 #include <linux/sunrpc/clnt.h> 37 #include <linux/sunrpc/addr.h> 38 #include <linux/sunrpc/sched.h> 39 #include <linux/sunrpc/svcsock.h> 40 #include <linux/sunrpc/xprtsock.h> 41 #include <linux/file.h> 42 #ifdef CONFIG_SUNRPC_BACKCHANNEL 43 #include <linux/sunrpc/bc_xprt.h> 44 #endif 45 46 #include <net/sock.h> 47 #include <net/checksum.h> 48 #include <net/udp.h> 49 #include <net/tcp.h> 50 #include <linux/bvec.h> 51 #include <linux/highmem.h> 52 #include <linux/uio.h> 53 #include <linux/sched/mm.h> 54 55 #include <trace/events/sunrpc.h> 56 57 #include "socklib.h" 58 #include "sunrpc.h" 59 60 static void xs_close(struct rpc_xprt *xprt); 61 static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt, 62 struct socket *sock); 63 64 /* 65 * xprtsock tunables 66 */ 67 static unsigned int xprt_udp_slot_table_entries = RPC_DEF_SLOT_TABLE; 68 static unsigned int xprt_tcp_slot_table_entries = RPC_MIN_SLOT_TABLE; 69 static unsigned int xprt_max_tcp_slot_table_entries = RPC_MAX_SLOT_TABLE; 70 71 static unsigned int xprt_min_resvport = RPC_DEF_MIN_RESVPORT; 72 static unsigned int xprt_max_resvport = RPC_DEF_MAX_RESVPORT; 73 74 #define XS_TCP_LINGER_TO (15U * HZ) 75 static unsigned int xs_tcp_fin_timeout __read_mostly = XS_TCP_LINGER_TO; 76 77 /* 78 * We can register our own files under /proc/sys/sunrpc by 79 * calling register_sysctl_table() again. The files in that 80 * directory become the union of all files registered there. 81 * 82 * We simply need to make sure that we don't collide with 83 * someone else's file names! 84 */ 85 86 static unsigned int min_slot_table_size = RPC_MIN_SLOT_TABLE; 87 static unsigned int max_slot_table_size = RPC_MAX_SLOT_TABLE; 88 static unsigned int max_tcp_slot_table_limit = RPC_MAX_SLOT_TABLE_LIMIT; 89 static unsigned int xprt_min_resvport_limit = RPC_MIN_RESVPORT; 90 static unsigned int xprt_max_resvport_limit = RPC_MAX_RESVPORT; 91 92 static struct ctl_table_header *sunrpc_table_header; 93 94 /* 95 * FIXME: changing the UDP slot table size should also resize the UDP 96 * socket buffers for existing UDP transports 97 */ 98 static struct ctl_table xs_tunables_table[] = { 99 { 100 .procname = "udp_slot_table_entries", 101 .data = &xprt_udp_slot_table_entries, 102 .maxlen = sizeof(unsigned int), 103 .mode = 0644, 104 .proc_handler = proc_dointvec_minmax, 105 .extra1 = &min_slot_table_size, 106 .extra2 = &max_slot_table_size 107 }, 108 { 109 .procname = "tcp_slot_table_entries", 110 .data = &xprt_tcp_slot_table_entries, 111 .maxlen = sizeof(unsigned int), 112 .mode = 0644, 113 .proc_handler = proc_dointvec_minmax, 114 .extra1 = &min_slot_table_size, 115 .extra2 = &max_slot_table_size 116 }, 117 { 118 .procname = "tcp_max_slot_table_entries", 119 .data = &xprt_max_tcp_slot_table_entries, 120 .maxlen = sizeof(unsigned int), 121 .mode = 0644, 122 .proc_handler = proc_dointvec_minmax, 123 .extra1 = &min_slot_table_size, 124 .extra2 = &max_tcp_slot_table_limit 125 }, 126 { 127 .procname = "min_resvport", 128 .data = &xprt_min_resvport, 129 .maxlen = sizeof(unsigned int), 130 .mode = 0644, 131 .proc_handler = proc_dointvec_minmax, 132 .extra1 = &xprt_min_resvport_limit, 133 .extra2 = &xprt_max_resvport_limit 134 }, 135 { 136 .procname = "max_resvport", 137 .data = &xprt_max_resvport, 138 .maxlen = sizeof(unsigned int), 139 .mode = 0644, 140 .proc_handler = proc_dointvec_minmax, 141 .extra1 = &xprt_min_resvport_limit, 142 .extra2 = &xprt_max_resvport_limit 143 }, 144 { 145 .procname = "tcp_fin_timeout", 146 .data = &xs_tcp_fin_timeout, 147 .maxlen = sizeof(xs_tcp_fin_timeout), 148 .mode = 0644, 149 .proc_handler = proc_dointvec_jiffies, 150 }, 151 { }, 152 }; 153 154 static struct ctl_table sunrpc_table[] = { 155 { 156 .procname = "sunrpc", 157 .mode = 0555, 158 .child = xs_tunables_table 159 }, 160 { }, 161 }; 162 163 /* 164 * Wait duration for a reply from the RPC portmapper. 165 */ 166 #define XS_BIND_TO (60U * HZ) 167 168 /* 169 * Delay if a UDP socket connect error occurs. This is most likely some 170 * kind of resource problem on the local host. 171 */ 172 #define XS_UDP_REEST_TO (2U * HZ) 173 174 /* 175 * The reestablish timeout allows clients to delay for a bit before attempting 176 * to reconnect to a server that just dropped our connection. 177 * 178 * We implement an exponential backoff when trying to reestablish a TCP 179 * transport connection with the server. Some servers like to drop a TCP 180 * connection when they are overworked, so we start with a short timeout and 181 * increase over time if the server is down or not responding. 182 */ 183 #define XS_TCP_INIT_REEST_TO (3U * HZ) 184 185 /* 186 * TCP idle timeout; client drops the transport socket if it is idle 187 * for this long. Note that we also timeout UDP sockets to prevent 188 * holding port numbers when there is no RPC traffic. 189 */ 190 #define XS_IDLE_DISC_TO (5U * 60 * HZ) 191 192 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 193 # undef RPC_DEBUG_DATA 194 # define RPCDBG_FACILITY RPCDBG_TRANS 195 #endif 196 197 #ifdef RPC_DEBUG_DATA 198 static void xs_pktdump(char *msg, u32 *packet, unsigned int count) 199 { 200 u8 *buf = (u8 *) packet; 201 int j; 202 203 dprintk("RPC: %s\n", msg); 204 for (j = 0; j < count && j < 128; j += 4) { 205 if (!(j & 31)) { 206 if (j) 207 dprintk("\n"); 208 dprintk("0x%04x ", j); 209 } 210 dprintk("%02x%02x%02x%02x ", 211 buf[j], buf[j+1], buf[j+2], buf[j+3]); 212 } 213 dprintk("\n"); 214 } 215 #else 216 static inline void xs_pktdump(char *msg, u32 *packet, unsigned int count) 217 { 218 /* NOP */ 219 } 220 #endif 221 222 static inline struct rpc_xprt *xprt_from_sock(struct sock *sk) 223 { 224 return (struct rpc_xprt *) sk->sk_user_data; 225 } 226 227 static inline struct sockaddr *xs_addr(struct rpc_xprt *xprt) 228 { 229 return (struct sockaddr *) &xprt->addr; 230 } 231 232 static inline struct sockaddr_un *xs_addr_un(struct rpc_xprt *xprt) 233 { 234 return (struct sockaddr_un *) &xprt->addr; 235 } 236 237 static inline struct sockaddr_in *xs_addr_in(struct rpc_xprt *xprt) 238 { 239 return (struct sockaddr_in *) &xprt->addr; 240 } 241 242 static inline struct sockaddr_in6 *xs_addr_in6(struct rpc_xprt *xprt) 243 { 244 return (struct sockaddr_in6 *) &xprt->addr; 245 } 246 247 static void xs_format_common_peer_addresses(struct rpc_xprt *xprt) 248 { 249 struct sockaddr *sap = xs_addr(xprt); 250 struct sockaddr_in6 *sin6; 251 struct sockaddr_in *sin; 252 struct sockaddr_un *sun; 253 char buf[128]; 254 255 switch (sap->sa_family) { 256 case AF_LOCAL: 257 sun = xs_addr_un(xprt); 258 strlcpy(buf, sun->sun_path, sizeof(buf)); 259 xprt->address_strings[RPC_DISPLAY_ADDR] = 260 kstrdup(buf, GFP_KERNEL); 261 break; 262 case AF_INET: 263 (void)rpc_ntop(sap, buf, sizeof(buf)); 264 xprt->address_strings[RPC_DISPLAY_ADDR] = 265 kstrdup(buf, GFP_KERNEL); 266 sin = xs_addr_in(xprt); 267 snprintf(buf, sizeof(buf), "%08x", ntohl(sin->sin_addr.s_addr)); 268 break; 269 case AF_INET6: 270 (void)rpc_ntop(sap, buf, sizeof(buf)); 271 xprt->address_strings[RPC_DISPLAY_ADDR] = 272 kstrdup(buf, GFP_KERNEL); 273 sin6 = xs_addr_in6(xprt); 274 snprintf(buf, sizeof(buf), "%pi6", &sin6->sin6_addr); 275 break; 276 default: 277 BUG(); 278 } 279 280 xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = kstrdup(buf, GFP_KERNEL); 281 } 282 283 static void xs_format_common_peer_ports(struct rpc_xprt *xprt) 284 { 285 struct sockaddr *sap = xs_addr(xprt); 286 char buf[128]; 287 288 snprintf(buf, sizeof(buf), "%u", rpc_get_port(sap)); 289 xprt->address_strings[RPC_DISPLAY_PORT] = kstrdup(buf, GFP_KERNEL); 290 291 snprintf(buf, sizeof(buf), "%4hx", rpc_get_port(sap)); 292 xprt->address_strings[RPC_DISPLAY_HEX_PORT] = kstrdup(buf, GFP_KERNEL); 293 } 294 295 static void xs_format_peer_addresses(struct rpc_xprt *xprt, 296 const char *protocol, 297 const char *netid) 298 { 299 xprt->address_strings[RPC_DISPLAY_PROTO] = protocol; 300 xprt->address_strings[RPC_DISPLAY_NETID] = netid; 301 xs_format_common_peer_addresses(xprt); 302 xs_format_common_peer_ports(xprt); 303 } 304 305 static void xs_update_peer_port(struct rpc_xprt *xprt) 306 { 307 kfree(xprt->address_strings[RPC_DISPLAY_HEX_PORT]); 308 kfree(xprt->address_strings[RPC_DISPLAY_PORT]); 309 310 xs_format_common_peer_ports(xprt); 311 } 312 313 static void xs_free_peer_addresses(struct rpc_xprt *xprt) 314 { 315 unsigned int i; 316 317 for (i = 0; i < RPC_DISPLAY_MAX; i++) 318 switch (i) { 319 case RPC_DISPLAY_PROTO: 320 case RPC_DISPLAY_NETID: 321 continue; 322 default: 323 kfree(xprt->address_strings[i]); 324 } 325 } 326 327 static size_t 328 xs_alloc_sparse_pages(struct xdr_buf *buf, size_t want, gfp_t gfp) 329 { 330 size_t i,n; 331 332 if (!want || !(buf->flags & XDRBUF_SPARSE_PAGES)) 333 return want; 334 n = (buf->page_base + want + PAGE_SIZE - 1) >> PAGE_SHIFT; 335 for (i = 0; i < n; i++) { 336 if (buf->pages[i]) 337 continue; 338 buf->bvec[i].bv_page = buf->pages[i] = alloc_page(gfp); 339 if (!buf->pages[i]) { 340 i *= PAGE_SIZE; 341 return i > buf->page_base ? i - buf->page_base : 0; 342 } 343 } 344 return want; 345 } 346 347 static ssize_t 348 xs_sock_recvmsg(struct socket *sock, struct msghdr *msg, int flags, size_t seek) 349 { 350 ssize_t ret; 351 if (seek != 0) 352 iov_iter_advance(&msg->msg_iter, seek); 353 ret = sock_recvmsg(sock, msg, flags); 354 return ret > 0 ? ret + seek : ret; 355 } 356 357 static ssize_t 358 xs_read_kvec(struct socket *sock, struct msghdr *msg, int flags, 359 struct kvec *kvec, size_t count, size_t seek) 360 { 361 iov_iter_kvec(&msg->msg_iter, READ, kvec, 1, count); 362 return xs_sock_recvmsg(sock, msg, flags, seek); 363 } 364 365 static ssize_t 366 xs_read_bvec(struct socket *sock, struct msghdr *msg, int flags, 367 struct bio_vec *bvec, unsigned long nr, size_t count, 368 size_t seek) 369 { 370 iov_iter_bvec(&msg->msg_iter, READ, bvec, nr, count); 371 return xs_sock_recvmsg(sock, msg, flags, seek); 372 } 373 374 static ssize_t 375 xs_read_discard(struct socket *sock, struct msghdr *msg, int flags, 376 size_t count) 377 { 378 iov_iter_discard(&msg->msg_iter, READ, count); 379 return sock_recvmsg(sock, msg, flags); 380 } 381 382 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 383 static void 384 xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek) 385 { 386 struct bvec_iter bi = { 387 .bi_size = count, 388 }; 389 struct bio_vec bv; 390 391 bvec_iter_advance(bvec, &bi, seek & PAGE_MASK); 392 for_each_bvec(bv, bvec, bi, bi) 393 flush_dcache_page(bv.bv_page); 394 } 395 #else 396 static inline void 397 xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek) 398 { 399 } 400 #endif 401 402 static ssize_t 403 xs_read_xdr_buf(struct socket *sock, struct msghdr *msg, int flags, 404 struct xdr_buf *buf, size_t count, size_t seek, size_t *read) 405 { 406 size_t want, seek_init = seek, offset = 0; 407 ssize_t ret; 408 409 want = min_t(size_t, count, buf->head[0].iov_len); 410 if (seek < want) { 411 ret = xs_read_kvec(sock, msg, flags, &buf->head[0], want, seek); 412 if (ret <= 0) 413 goto sock_err; 414 offset += ret; 415 if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC)) 416 goto out; 417 if (ret != want) 418 goto out; 419 seek = 0; 420 } else { 421 seek -= want; 422 offset += want; 423 } 424 425 want = xs_alloc_sparse_pages(buf, 426 min_t(size_t, count - offset, buf->page_len), 427 GFP_KERNEL); 428 if (seek < want) { 429 ret = xs_read_bvec(sock, msg, flags, buf->bvec, 430 xdr_buf_pagecount(buf), 431 want + buf->page_base, 432 seek + buf->page_base); 433 if (ret <= 0) 434 goto sock_err; 435 xs_flush_bvec(buf->bvec, ret, seek + buf->page_base); 436 offset += ret - buf->page_base; 437 if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC)) 438 goto out; 439 if (ret != want) 440 goto out; 441 seek = 0; 442 } else { 443 seek -= want; 444 offset += want; 445 } 446 447 want = min_t(size_t, count - offset, buf->tail[0].iov_len); 448 if (seek < want) { 449 ret = xs_read_kvec(sock, msg, flags, &buf->tail[0], want, seek); 450 if (ret <= 0) 451 goto sock_err; 452 offset += ret; 453 if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC)) 454 goto out; 455 if (ret != want) 456 goto out; 457 } else if (offset < seek_init) 458 offset = seek_init; 459 ret = -EMSGSIZE; 460 out: 461 *read = offset - seek_init; 462 return ret; 463 sock_err: 464 offset += seek; 465 goto out; 466 } 467 468 static void 469 xs_read_header(struct sock_xprt *transport, struct xdr_buf *buf) 470 { 471 if (!transport->recv.copied) { 472 if (buf->head[0].iov_len >= transport->recv.offset) 473 memcpy(buf->head[0].iov_base, 474 &transport->recv.xid, 475 transport->recv.offset); 476 transport->recv.copied = transport->recv.offset; 477 } 478 } 479 480 static bool 481 xs_read_stream_request_done(struct sock_xprt *transport) 482 { 483 return transport->recv.fraghdr & cpu_to_be32(RPC_LAST_STREAM_FRAGMENT); 484 } 485 486 static void 487 xs_read_stream_check_eor(struct sock_xprt *transport, 488 struct msghdr *msg) 489 { 490 if (xs_read_stream_request_done(transport)) 491 msg->msg_flags |= MSG_EOR; 492 } 493 494 static ssize_t 495 xs_read_stream_request(struct sock_xprt *transport, struct msghdr *msg, 496 int flags, struct rpc_rqst *req) 497 { 498 struct xdr_buf *buf = &req->rq_private_buf; 499 size_t want, read; 500 ssize_t ret; 501 502 xs_read_header(transport, buf); 503 504 want = transport->recv.len - transport->recv.offset; 505 if (want != 0) { 506 ret = xs_read_xdr_buf(transport->sock, msg, flags, buf, 507 transport->recv.copied + want, 508 transport->recv.copied, 509 &read); 510 transport->recv.offset += read; 511 transport->recv.copied += read; 512 } 513 514 if (transport->recv.offset == transport->recv.len) 515 xs_read_stream_check_eor(transport, msg); 516 517 if (want == 0) 518 return 0; 519 520 switch (ret) { 521 default: 522 break; 523 case -EFAULT: 524 case -EMSGSIZE: 525 msg->msg_flags |= MSG_TRUNC; 526 return read; 527 case 0: 528 return -ESHUTDOWN; 529 } 530 return ret < 0 ? ret : read; 531 } 532 533 static size_t 534 xs_read_stream_headersize(bool isfrag) 535 { 536 if (isfrag) 537 return sizeof(__be32); 538 return 3 * sizeof(__be32); 539 } 540 541 static ssize_t 542 xs_read_stream_header(struct sock_xprt *transport, struct msghdr *msg, 543 int flags, size_t want, size_t seek) 544 { 545 struct kvec kvec = { 546 .iov_base = &transport->recv.fraghdr, 547 .iov_len = want, 548 }; 549 return xs_read_kvec(transport->sock, msg, flags, &kvec, want, seek); 550 } 551 552 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 553 static ssize_t 554 xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags) 555 { 556 struct rpc_xprt *xprt = &transport->xprt; 557 struct rpc_rqst *req; 558 ssize_t ret; 559 560 /* Look up and lock the request corresponding to the given XID */ 561 req = xprt_lookup_bc_request(xprt, transport->recv.xid); 562 if (!req) { 563 printk(KERN_WARNING "Callback slot table overflowed\n"); 564 return -ESHUTDOWN; 565 } 566 if (transport->recv.copied && !req->rq_private_buf.len) 567 return -ESHUTDOWN; 568 569 ret = xs_read_stream_request(transport, msg, flags, req); 570 if (msg->msg_flags & (MSG_EOR|MSG_TRUNC)) 571 xprt_complete_bc_request(req, transport->recv.copied); 572 else 573 req->rq_private_buf.len = transport->recv.copied; 574 575 return ret; 576 } 577 #else /* CONFIG_SUNRPC_BACKCHANNEL */ 578 static ssize_t 579 xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags) 580 { 581 return -ESHUTDOWN; 582 } 583 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 584 585 static ssize_t 586 xs_read_stream_reply(struct sock_xprt *transport, struct msghdr *msg, int flags) 587 { 588 struct rpc_xprt *xprt = &transport->xprt; 589 struct rpc_rqst *req; 590 ssize_t ret = 0; 591 592 /* Look up and lock the request corresponding to the given XID */ 593 spin_lock(&xprt->queue_lock); 594 req = xprt_lookup_rqst(xprt, transport->recv.xid); 595 if (!req || (transport->recv.copied && !req->rq_private_buf.len)) { 596 msg->msg_flags |= MSG_TRUNC; 597 goto out; 598 } 599 xprt_pin_rqst(req); 600 spin_unlock(&xprt->queue_lock); 601 602 ret = xs_read_stream_request(transport, msg, flags, req); 603 604 spin_lock(&xprt->queue_lock); 605 if (msg->msg_flags & (MSG_EOR|MSG_TRUNC)) 606 xprt_complete_rqst(req->rq_task, transport->recv.copied); 607 else 608 req->rq_private_buf.len = transport->recv.copied; 609 xprt_unpin_rqst(req); 610 out: 611 spin_unlock(&xprt->queue_lock); 612 return ret; 613 } 614 615 static ssize_t 616 xs_read_stream(struct sock_xprt *transport, int flags) 617 { 618 struct msghdr msg = { 0 }; 619 size_t want, read = 0; 620 ssize_t ret = 0; 621 622 if (transport->recv.len == 0) { 623 want = xs_read_stream_headersize(transport->recv.copied != 0); 624 ret = xs_read_stream_header(transport, &msg, flags, want, 625 transport->recv.offset); 626 if (ret <= 0) 627 goto out_err; 628 transport->recv.offset = ret; 629 if (transport->recv.offset != want) 630 return transport->recv.offset; 631 transport->recv.len = be32_to_cpu(transport->recv.fraghdr) & 632 RPC_FRAGMENT_SIZE_MASK; 633 transport->recv.offset -= sizeof(transport->recv.fraghdr); 634 read = ret; 635 } 636 637 switch (be32_to_cpu(transport->recv.calldir)) { 638 default: 639 msg.msg_flags |= MSG_TRUNC; 640 break; 641 case RPC_CALL: 642 ret = xs_read_stream_call(transport, &msg, flags); 643 break; 644 case RPC_REPLY: 645 ret = xs_read_stream_reply(transport, &msg, flags); 646 } 647 if (msg.msg_flags & MSG_TRUNC) { 648 transport->recv.calldir = cpu_to_be32(-1); 649 transport->recv.copied = -1; 650 } 651 if (ret < 0) 652 goto out_err; 653 read += ret; 654 if (transport->recv.offset < transport->recv.len) { 655 if (!(msg.msg_flags & MSG_TRUNC)) 656 return read; 657 msg.msg_flags = 0; 658 ret = xs_read_discard(transport->sock, &msg, flags, 659 transport->recv.len - transport->recv.offset); 660 if (ret <= 0) 661 goto out_err; 662 transport->recv.offset += ret; 663 read += ret; 664 if (transport->recv.offset != transport->recv.len) 665 return read; 666 } 667 if (xs_read_stream_request_done(transport)) { 668 trace_xs_stream_read_request(transport); 669 transport->recv.copied = 0; 670 } 671 transport->recv.offset = 0; 672 transport->recv.len = 0; 673 return read; 674 out_err: 675 return ret != 0 ? ret : -ESHUTDOWN; 676 } 677 678 static __poll_t xs_poll_socket(struct sock_xprt *transport) 679 { 680 return transport->sock->ops->poll(transport->file, transport->sock, 681 NULL); 682 } 683 684 static bool xs_poll_socket_readable(struct sock_xprt *transport) 685 { 686 __poll_t events = xs_poll_socket(transport); 687 688 return (events & (EPOLLIN | EPOLLRDNORM)) && !(events & EPOLLRDHUP); 689 } 690 691 static void xs_poll_check_readable(struct sock_xprt *transport) 692 { 693 694 clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state); 695 if (!xs_poll_socket_readable(transport)) 696 return; 697 if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state)) 698 queue_work(xprtiod_workqueue, &transport->recv_worker); 699 } 700 701 static void xs_stream_data_receive(struct sock_xprt *transport) 702 { 703 size_t read = 0; 704 ssize_t ret = 0; 705 706 mutex_lock(&transport->recv_mutex); 707 if (transport->sock == NULL) 708 goto out; 709 for (;;) { 710 ret = xs_read_stream(transport, MSG_DONTWAIT); 711 if (ret < 0) 712 break; 713 read += ret; 714 cond_resched(); 715 } 716 if (ret == -ESHUTDOWN) 717 kernel_sock_shutdown(transport->sock, SHUT_RDWR); 718 else 719 xs_poll_check_readable(transport); 720 out: 721 mutex_unlock(&transport->recv_mutex); 722 trace_xs_stream_read_data(&transport->xprt, ret, read); 723 } 724 725 static void xs_stream_data_receive_workfn(struct work_struct *work) 726 { 727 struct sock_xprt *transport = 728 container_of(work, struct sock_xprt, recv_worker); 729 unsigned int pflags = memalloc_nofs_save(); 730 731 xs_stream_data_receive(transport); 732 memalloc_nofs_restore(pflags); 733 } 734 735 static void 736 xs_stream_reset_connect(struct sock_xprt *transport) 737 { 738 transport->recv.offset = 0; 739 transport->recv.len = 0; 740 transport->recv.copied = 0; 741 transport->xmit.offset = 0; 742 } 743 744 static void 745 xs_stream_start_connect(struct sock_xprt *transport) 746 { 747 transport->xprt.stat.connect_count++; 748 transport->xprt.stat.connect_start = jiffies; 749 } 750 751 #define XS_SENDMSG_FLAGS (MSG_DONTWAIT | MSG_NOSIGNAL) 752 753 /** 754 * xs_nospace - handle transmit was incomplete 755 * @req: pointer to RPC request 756 * 757 */ 758 static int xs_nospace(struct rpc_rqst *req) 759 { 760 struct rpc_xprt *xprt = req->rq_xprt; 761 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); 762 struct sock *sk = transport->inet; 763 int ret = -EAGAIN; 764 765 trace_rpc_socket_nospace(req, transport); 766 767 /* Protect against races with write_space */ 768 spin_lock(&xprt->transport_lock); 769 770 /* Don't race with disconnect */ 771 if (xprt_connected(xprt)) { 772 /* wait for more buffer space */ 773 sk->sk_write_pending++; 774 xprt_wait_for_buffer_space(xprt); 775 } else 776 ret = -ENOTCONN; 777 778 spin_unlock(&xprt->transport_lock); 779 780 /* Race breaker in case memory is freed before above code is called */ 781 if (ret == -EAGAIN) { 782 struct socket_wq *wq; 783 784 rcu_read_lock(); 785 wq = rcu_dereference(sk->sk_wq); 786 set_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags); 787 rcu_read_unlock(); 788 789 sk->sk_write_space(sk); 790 } 791 return ret; 792 } 793 794 static void 795 xs_stream_prepare_request(struct rpc_rqst *req) 796 { 797 xdr_free_bvec(&req->rq_rcv_buf); 798 req->rq_task->tk_status = xdr_alloc_bvec(&req->rq_rcv_buf, GFP_KERNEL); 799 } 800 801 /* 802 * Determine if the previous message in the stream was aborted before it 803 * could complete transmission. 804 */ 805 static bool 806 xs_send_request_was_aborted(struct sock_xprt *transport, struct rpc_rqst *req) 807 { 808 return transport->xmit.offset != 0 && req->rq_bytes_sent == 0; 809 } 810 811 /* 812 * Return the stream record marker field for a record of length < 2^31-1 813 */ 814 static rpc_fraghdr 815 xs_stream_record_marker(struct xdr_buf *xdr) 816 { 817 if (!xdr->len) 818 return 0; 819 return cpu_to_be32(RPC_LAST_STREAM_FRAGMENT | (u32)xdr->len); 820 } 821 822 /** 823 * xs_local_send_request - write an RPC request to an AF_LOCAL socket 824 * @req: pointer to RPC request 825 * 826 * Return values: 827 * 0: The request has been sent 828 * EAGAIN: The socket was blocked, please call again later to 829 * complete the request 830 * ENOTCONN: Caller needs to invoke connect logic then call again 831 * other: Some other error occured, the request was not sent 832 */ 833 static int xs_local_send_request(struct rpc_rqst *req) 834 { 835 struct rpc_xprt *xprt = req->rq_xprt; 836 struct sock_xprt *transport = 837 container_of(xprt, struct sock_xprt, xprt); 838 struct xdr_buf *xdr = &req->rq_snd_buf; 839 rpc_fraghdr rm = xs_stream_record_marker(xdr); 840 unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen; 841 struct msghdr msg = { 842 .msg_flags = XS_SENDMSG_FLAGS, 843 }; 844 unsigned int sent; 845 int status; 846 847 /* Close the stream if the previous transmission was incomplete */ 848 if (xs_send_request_was_aborted(transport, req)) { 849 xs_close(xprt); 850 return -ENOTCONN; 851 } 852 853 xs_pktdump("packet data:", 854 req->rq_svec->iov_base, req->rq_svec->iov_len); 855 856 req->rq_xtime = ktime_get(); 857 status = xprt_sock_sendmsg(transport->sock, &msg, xdr, 858 transport->xmit.offset, rm, &sent); 859 dprintk("RPC: %s(%u) = %d\n", 860 __func__, xdr->len - transport->xmit.offset, status); 861 862 if (status == -EAGAIN && sock_writeable(transport->inet)) 863 status = -ENOBUFS; 864 865 if (likely(sent > 0) || status == 0) { 866 transport->xmit.offset += sent; 867 req->rq_bytes_sent = transport->xmit.offset; 868 if (likely(req->rq_bytes_sent >= msglen)) { 869 req->rq_xmit_bytes_sent += transport->xmit.offset; 870 transport->xmit.offset = 0; 871 return 0; 872 } 873 status = -EAGAIN; 874 } 875 876 switch (status) { 877 case -ENOBUFS: 878 break; 879 case -EAGAIN: 880 status = xs_nospace(req); 881 break; 882 default: 883 dprintk("RPC: sendmsg returned unrecognized error %d\n", 884 -status); 885 fallthrough; 886 case -EPIPE: 887 xs_close(xprt); 888 status = -ENOTCONN; 889 } 890 891 return status; 892 } 893 894 /** 895 * xs_udp_send_request - write an RPC request to a UDP socket 896 * @req: pointer to RPC request 897 * 898 * Return values: 899 * 0: The request has been sent 900 * EAGAIN: The socket was blocked, please call again later to 901 * complete the request 902 * ENOTCONN: Caller needs to invoke connect logic then call again 903 * other: Some other error occurred, the request was not sent 904 */ 905 static int xs_udp_send_request(struct rpc_rqst *req) 906 { 907 struct rpc_xprt *xprt = req->rq_xprt; 908 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); 909 struct xdr_buf *xdr = &req->rq_snd_buf; 910 struct msghdr msg = { 911 .msg_name = xs_addr(xprt), 912 .msg_namelen = xprt->addrlen, 913 .msg_flags = XS_SENDMSG_FLAGS, 914 }; 915 unsigned int sent; 916 int status; 917 918 xs_pktdump("packet data:", 919 req->rq_svec->iov_base, 920 req->rq_svec->iov_len); 921 922 if (!xprt_bound(xprt)) 923 return -ENOTCONN; 924 925 if (!xprt_request_get_cong(xprt, req)) 926 return -EBADSLT; 927 928 req->rq_xtime = ktime_get(); 929 status = xprt_sock_sendmsg(transport->sock, &msg, xdr, 0, 0, &sent); 930 931 dprintk("RPC: xs_udp_send_request(%u) = %d\n", 932 xdr->len, status); 933 934 /* firewall is blocking us, don't return -EAGAIN or we end up looping */ 935 if (status == -EPERM) 936 goto process_status; 937 938 if (status == -EAGAIN && sock_writeable(transport->inet)) 939 status = -ENOBUFS; 940 941 if (sent > 0 || status == 0) { 942 req->rq_xmit_bytes_sent += sent; 943 if (sent >= req->rq_slen) 944 return 0; 945 /* Still some bytes left; set up for a retry later. */ 946 status = -EAGAIN; 947 } 948 949 process_status: 950 switch (status) { 951 case -ENOTSOCK: 952 status = -ENOTCONN; 953 /* Should we call xs_close() here? */ 954 break; 955 case -EAGAIN: 956 status = xs_nospace(req); 957 break; 958 case -ENETUNREACH: 959 case -ENOBUFS: 960 case -EPIPE: 961 case -ECONNREFUSED: 962 case -EPERM: 963 /* When the server has died, an ICMP port unreachable message 964 * prompts ECONNREFUSED. */ 965 break; 966 default: 967 dprintk("RPC: sendmsg returned unrecognized error %d\n", 968 -status); 969 } 970 971 return status; 972 } 973 974 /** 975 * xs_tcp_send_request - write an RPC request to a TCP socket 976 * @req: pointer to RPC request 977 * 978 * Return values: 979 * 0: The request has been sent 980 * EAGAIN: The socket was blocked, please call again later to 981 * complete the request 982 * ENOTCONN: Caller needs to invoke connect logic then call again 983 * other: Some other error occurred, the request was not sent 984 * 985 * XXX: In the case of soft timeouts, should we eventually give up 986 * if sendmsg is not able to make progress? 987 */ 988 static int xs_tcp_send_request(struct rpc_rqst *req) 989 { 990 struct rpc_xprt *xprt = req->rq_xprt; 991 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); 992 struct xdr_buf *xdr = &req->rq_snd_buf; 993 rpc_fraghdr rm = xs_stream_record_marker(xdr); 994 unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen; 995 struct msghdr msg = { 996 .msg_flags = XS_SENDMSG_FLAGS, 997 }; 998 bool vm_wait = false; 999 unsigned int sent; 1000 int status; 1001 1002 /* Close the stream if the previous transmission was incomplete */ 1003 if (xs_send_request_was_aborted(transport, req)) { 1004 if (transport->sock != NULL) 1005 kernel_sock_shutdown(transport->sock, SHUT_RDWR); 1006 return -ENOTCONN; 1007 } 1008 1009 xs_pktdump("packet data:", 1010 req->rq_svec->iov_base, 1011 req->rq_svec->iov_len); 1012 1013 if (test_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state)) 1014 xs_tcp_set_socket_timeouts(xprt, transport->sock); 1015 1016 /* Continue transmitting the packet/record. We must be careful 1017 * to cope with writespace callbacks arriving _after_ we have 1018 * called sendmsg(). */ 1019 req->rq_xtime = ktime_get(); 1020 while (1) { 1021 status = xprt_sock_sendmsg(transport->sock, &msg, xdr, 1022 transport->xmit.offset, rm, &sent); 1023 1024 dprintk("RPC: xs_tcp_send_request(%u) = %d\n", 1025 xdr->len - transport->xmit.offset, status); 1026 1027 /* If we've sent the entire packet, immediately 1028 * reset the count of bytes sent. */ 1029 transport->xmit.offset += sent; 1030 req->rq_bytes_sent = transport->xmit.offset; 1031 if (likely(req->rq_bytes_sent >= msglen)) { 1032 req->rq_xmit_bytes_sent += transport->xmit.offset; 1033 transport->xmit.offset = 0; 1034 return 0; 1035 } 1036 1037 WARN_ON_ONCE(sent == 0 && status == 0); 1038 1039 if (status == -EAGAIN ) { 1040 /* 1041 * Return EAGAIN if we're sure we're hitting the 1042 * socket send buffer limits. 1043 */ 1044 if (test_bit(SOCK_NOSPACE, &transport->sock->flags)) 1045 break; 1046 /* 1047 * Did we hit a memory allocation failure? 1048 */ 1049 if (sent == 0) { 1050 status = -ENOBUFS; 1051 if (vm_wait) 1052 break; 1053 /* Retry, knowing now that we're below the 1054 * socket send buffer limit 1055 */ 1056 vm_wait = true; 1057 } 1058 continue; 1059 } 1060 if (status < 0) 1061 break; 1062 vm_wait = false; 1063 } 1064 1065 switch (status) { 1066 case -ENOTSOCK: 1067 status = -ENOTCONN; 1068 /* Should we call xs_close() here? */ 1069 break; 1070 case -EAGAIN: 1071 status = xs_nospace(req); 1072 break; 1073 case -ECONNRESET: 1074 case -ECONNREFUSED: 1075 case -ENOTCONN: 1076 case -EADDRINUSE: 1077 case -ENOBUFS: 1078 case -EPIPE: 1079 break; 1080 default: 1081 dprintk("RPC: sendmsg returned unrecognized error %d\n", 1082 -status); 1083 } 1084 1085 return status; 1086 } 1087 1088 static void xs_save_old_callbacks(struct sock_xprt *transport, struct sock *sk) 1089 { 1090 transport->old_data_ready = sk->sk_data_ready; 1091 transport->old_state_change = sk->sk_state_change; 1092 transport->old_write_space = sk->sk_write_space; 1093 transport->old_error_report = sk->sk_error_report; 1094 } 1095 1096 static void xs_restore_old_callbacks(struct sock_xprt *transport, struct sock *sk) 1097 { 1098 sk->sk_data_ready = transport->old_data_ready; 1099 sk->sk_state_change = transport->old_state_change; 1100 sk->sk_write_space = transport->old_write_space; 1101 sk->sk_error_report = transport->old_error_report; 1102 } 1103 1104 static void xs_sock_reset_state_flags(struct rpc_xprt *xprt) 1105 { 1106 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); 1107 1108 clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state); 1109 clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state); 1110 clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state); 1111 clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state); 1112 } 1113 1114 static void xs_run_error_worker(struct sock_xprt *transport, unsigned int nr) 1115 { 1116 set_bit(nr, &transport->sock_state); 1117 queue_work(xprtiod_workqueue, &transport->error_worker); 1118 } 1119 1120 static void xs_sock_reset_connection_flags(struct rpc_xprt *xprt) 1121 { 1122 smp_mb__before_atomic(); 1123 clear_bit(XPRT_CLOSE_WAIT, &xprt->state); 1124 clear_bit(XPRT_CLOSING, &xprt->state); 1125 xs_sock_reset_state_flags(xprt); 1126 smp_mb__after_atomic(); 1127 } 1128 1129 /** 1130 * xs_error_report - callback to handle TCP socket state errors 1131 * @sk: socket 1132 * 1133 * Note: we don't call sock_error() since there may be a rpc_task 1134 * using the socket, and so we don't want to clear sk->sk_err. 1135 */ 1136 static void xs_error_report(struct sock *sk) 1137 { 1138 struct sock_xprt *transport; 1139 struct rpc_xprt *xprt; 1140 1141 read_lock_bh(&sk->sk_callback_lock); 1142 if (!(xprt = xprt_from_sock(sk))) 1143 goto out; 1144 1145 transport = container_of(xprt, struct sock_xprt, xprt); 1146 transport->xprt_err = -sk->sk_err; 1147 if (transport->xprt_err == 0) 1148 goto out; 1149 dprintk("RPC: xs_error_report client %p, error=%d...\n", 1150 xprt, -transport->xprt_err); 1151 trace_rpc_socket_error(xprt, sk->sk_socket, transport->xprt_err); 1152 1153 /* barrier ensures xprt_err is set before XPRT_SOCK_WAKE_ERROR */ 1154 smp_mb__before_atomic(); 1155 xs_run_error_worker(transport, XPRT_SOCK_WAKE_ERROR); 1156 out: 1157 read_unlock_bh(&sk->sk_callback_lock); 1158 } 1159 1160 static void xs_reset_transport(struct sock_xprt *transport) 1161 { 1162 struct socket *sock = transport->sock; 1163 struct sock *sk = transport->inet; 1164 struct rpc_xprt *xprt = &transport->xprt; 1165 struct file *filp = transport->file; 1166 1167 if (sk == NULL) 1168 return; 1169 1170 if (atomic_read(&transport->xprt.swapper)) 1171 sk_clear_memalloc(sk); 1172 1173 kernel_sock_shutdown(sock, SHUT_RDWR); 1174 1175 mutex_lock(&transport->recv_mutex); 1176 write_lock_bh(&sk->sk_callback_lock); 1177 transport->inet = NULL; 1178 transport->sock = NULL; 1179 transport->file = NULL; 1180 1181 sk->sk_user_data = NULL; 1182 1183 xs_restore_old_callbacks(transport, sk); 1184 xprt_clear_connected(xprt); 1185 write_unlock_bh(&sk->sk_callback_lock); 1186 xs_sock_reset_connection_flags(xprt); 1187 /* Reset stream record info */ 1188 xs_stream_reset_connect(transport); 1189 mutex_unlock(&transport->recv_mutex); 1190 1191 trace_rpc_socket_close(xprt, sock); 1192 fput(filp); 1193 1194 xprt_disconnect_done(xprt); 1195 } 1196 1197 /** 1198 * xs_close - close a socket 1199 * @xprt: transport 1200 * 1201 * This is used when all requests are complete; ie, no DRC state remains 1202 * on the server we want to save. 1203 * 1204 * The caller _must_ be holding XPRT_LOCKED in order to avoid issues with 1205 * xs_reset_transport() zeroing the socket from underneath a writer. 1206 */ 1207 static void xs_close(struct rpc_xprt *xprt) 1208 { 1209 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); 1210 1211 dprintk("RPC: xs_close xprt %p\n", xprt); 1212 1213 xs_reset_transport(transport); 1214 xprt->reestablish_timeout = 0; 1215 } 1216 1217 static void xs_inject_disconnect(struct rpc_xprt *xprt) 1218 { 1219 dprintk("RPC: injecting transport disconnect on xprt=%p\n", 1220 xprt); 1221 xprt_disconnect_done(xprt); 1222 } 1223 1224 static void xs_xprt_free(struct rpc_xprt *xprt) 1225 { 1226 xs_free_peer_addresses(xprt); 1227 xprt_free(xprt); 1228 } 1229 1230 /** 1231 * xs_destroy - prepare to shutdown a transport 1232 * @xprt: doomed transport 1233 * 1234 */ 1235 static void xs_destroy(struct rpc_xprt *xprt) 1236 { 1237 struct sock_xprt *transport = container_of(xprt, 1238 struct sock_xprt, xprt); 1239 dprintk("RPC: xs_destroy xprt %p\n", xprt); 1240 1241 cancel_delayed_work_sync(&transport->connect_worker); 1242 xs_close(xprt); 1243 cancel_work_sync(&transport->recv_worker); 1244 cancel_work_sync(&transport->error_worker); 1245 xs_xprt_free(xprt); 1246 module_put(THIS_MODULE); 1247 } 1248 1249 /** 1250 * xs_udp_data_read_skb - receive callback for UDP sockets 1251 * @xprt: transport 1252 * @sk: socket 1253 * @skb: skbuff 1254 * 1255 */ 1256 static void xs_udp_data_read_skb(struct rpc_xprt *xprt, 1257 struct sock *sk, 1258 struct sk_buff *skb) 1259 { 1260 struct rpc_task *task; 1261 struct rpc_rqst *rovr; 1262 int repsize, copied; 1263 u32 _xid; 1264 __be32 *xp; 1265 1266 repsize = skb->len; 1267 if (repsize < 4) { 1268 dprintk("RPC: impossible RPC reply size %d!\n", repsize); 1269 return; 1270 } 1271 1272 /* Copy the XID from the skb... */ 1273 xp = skb_header_pointer(skb, 0, sizeof(_xid), &_xid); 1274 if (xp == NULL) 1275 return; 1276 1277 /* Look up and lock the request corresponding to the given XID */ 1278 spin_lock(&xprt->queue_lock); 1279 rovr = xprt_lookup_rqst(xprt, *xp); 1280 if (!rovr) 1281 goto out_unlock; 1282 xprt_pin_rqst(rovr); 1283 xprt_update_rtt(rovr->rq_task); 1284 spin_unlock(&xprt->queue_lock); 1285 task = rovr->rq_task; 1286 1287 if ((copied = rovr->rq_private_buf.buflen) > repsize) 1288 copied = repsize; 1289 1290 /* Suck it into the iovec, verify checksum if not done by hw. */ 1291 if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb)) { 1292 spin_lock(&xprt->queue_lock); 1293 __UDPX_INC_STATS(sk, UDP_MIB_INERRORS); 1294 goto out_unpin; 1295 } 1296 1297 1298 spin_lock(&xprt->transport_lock); 1299 xprt_adjust_cwnd(xprt, task, copied); 1300 spin_unlock(&xprt->transport_lock); 1301 spin_lock(&xprt->queue_lock); 1302 xprt_complete_rqst(task, copied); 1303 __UDPX_INC_STATS(sk, UDP_MIB_INDATAGRAMS); 1304 out_unpin: 1305 xprt_unpin_rqst(rovr); 1306 out_unlock: 1307 spin_unlock(&xprt->queue_lock); 1308 } 1309 1310 static void xs_udp_data_receive(struct sock_xprt *transport) 1311 { 1312 struct sk_buff *skb; 1313 struct sock *sk; 1314 int err; 1315 1316 mutex_lock(&transport->recv_mutex); 1317 sk = transport->inet; 1318 if (sk == NULL) 1319 goto out; 1320 for (;;) { 1321 skb = skb_recv_udp(sk, 0, 1, &err); 1322 if (skb == NULL) 1323 break; 1324 xs_udp_data_read_skb(&transport->xprt, sk, skb); 1325 consume_skb(skb); 1326 cond_resched(); 1327 } 1328 xs_poll_check_readable(transport); 1329 out: 1330 mutex_unlock(&transport->recv_mutex); 1331 } 1332 1333 static void xs_udp_data_receive_workfn(struct work_struct *work) 1334 { 1335 struct sock_xprt *transport = 1336 container_of(work, struct sock_xprt, recv_worker); 1337 unsigned int pflags = memalloc_nofs_save(); 1338 1339 xs_udp_data_receive(transport); 1340 memalloc_nofs_restore(pflags); 1341 } 1342 1343 /** 1344 * xs_data_ready - "data ready" callback for UDP sockets 1345 * @sk: socket with data to read 1346 * 1347 */ 1348 static void xs_data_ready(struct sock *sk) 1349 { 1350 struct rpc_xprt *xprt; 1351 1352 read_lock_bh(&sk->sk_callback_lock); 1353 dprintk("RPC: xs_data_ready...\n"); 1354 xprt = xprt_from_sock(sk); 1355 if (xprt != NULL) { 1356 struct sock_xprt *transport = container_of(xprt, 1357 struct sock_xprt, xprt); 1358 transport->old_data_ready(sk); 1359 /* Any data means we had a useful conversation, so 1360 * then we don't need to delay the next reconnect 1361 */ 1362 if (xprt->reestablish_timeout) 1363 xprt->reestablish_timeout = 0; 1364 if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state)) 1365 queue_work(xprtiod_workqueue, &transport->recv_worker); 1366 } 1367 read_unlock_bh(&sk->sk_callback_lock); 1368 } 1369 1370 /* 1371 * Helper function to force a TCP close if the server is sending 1372 * junk and/or it has put us in CLOSE_WAIT 1373 */ 1374 static void xs_tcp_force_close(struct rpc_xprt *xprt) 1375 { 1376 xprt_force_disconnect(xprt); 1377 } 1378 1379 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 1380 static size_t xs_tcp_bc_maxpayload(struct rpc_xprt *xprt) 1381 { 1382 return PAGE_SIZE; 1383 } 1384 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 1385 1386 /** 1387 * xs_tcp_state_change - callback to handle TCP socket state changes 1388 * @sk: socket whose state has changed 1389 * 1390 */ 1391 static void xs_tcp_state_change(struct sock *sk) 1392 { 1393 struct rpc_xprt *xprt; 1394 struct sock_xprt *transport; 1395 1396 read_lock_bh(&sk->sk_callback_lock); 1397 if (!(xprt = xprt_from_sock(sk))) 1398 goto out; 1399 dprintk("RPC: xs_tcp_state_change client %p...\n", xprt); 1400 dprintk("RPC: state %x conn %d dead %d zapped %d sk_shutdown %d\n", 1401 sk->sk_state, xprt_connected(xprt), 1402 sock_flag(sk, SOCK_DEAD), 1403 sock_flag(sk, SOCK_ZAPPED), 1404 sk->sk_shutdown); 1405 1406 transport = container_of(xprt, struct sock_xprt, xprt); 1407 trace_rpc_socket_state_change(xprt, sk->sk_socket); 1408 switch (sk->sk_state) { 1409 case TCP_ESTABLISHED: 1410 if (!xprt_test_and_set_connected(xprt)) { 1411 xprt->connect_cookie++; 1412 clear_bit(XPRT_SOCK_CONNECTING, &transport->sock_state); 1413 xprt_clear_connecting(xprt); 1414 1415 xprt->stat.connect_count++; 1416 xprt->stat.connect_time += (long)jiffies - 1417 xprt->stat.connect_start; 1418 xs_run_error_worker(transport, XPRT_SOCK_WAKE_PENDING); 1419 } 1420 break; 1421 case TCP_FIN_WAIT1: 1422 /* The client initiated a shutdown of the socket */ 1423 xprt->connect_cookie++; 1424 xprt->reestablish_timeout = 0; 1425 set_bit(XPRT_CLOSING, &xprt->state); 1426 smp_mb__before_atomic(); 1427 clear_bit(XPRT_CONNECTED, &xprt->state); 1428 clear_bit(XPRT_CLOSE_WAIT, &xprt->state); 1429 smp_mb__after_atomic(); 1430 break; 1431 case TCP_CLOSE_WAIT: 1432 /* The server initiated a shutdown of the socket */ 1433 xprt->connect_cookie++; 1434 clear_bit(XPRT_CONNECTED, &xprt->state); 1435 xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT); 1436 fallthrough; 1437 case TCP_CLOSING: 1438 /* 1439 * If the server closed down the connection, make sure that 1440 * we back off before reconnecting 1441 */ 1442 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO) 1443 xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO; 1444 break; 1445 case TCP_LAST_ACK: 1446 set_bit(XPRT_CLOSING, &xprt->state); 1447 smp_mb__before_atomic(); 1448 clear_bit(XPRT_CONNECTED, &xprt->state); 1449 smp_mb__after_atomic(); 1450 break; 1451 case TCP_CLOSE: 1452 if (test_and_clear_bit(XPRT_SOCK_CONNECTING, 1453 &transport->sock_state)) 1454 xprt_clear_connecting(xprt); 1455 clear_bit(XPRT_CLOSING, &xprt->state); 1456 /* Trigger the socket release */ 1457 xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT); 1458 } 1459 out: 1460 read_unlock_bh(&sk->sk_callback_lock); 1461 } 1462 1463 static void xs_write_space(struct sock *sk) 1464 { 1465 struct socket_wq *wq; 1466 struct sock_xprt *transport; 1467 struct rpc_xprt *xprt; 1468 1469 if (!sk->sk_socket) 1470 return; 1471 clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 1472 1473 if (unlikely(!(xprt = xprt_from_sock(sk)))) 1474 return; 1475 transport = container_of(xprt, struct sock_xprt, xprt); 1476 rcu_read_lock(); 1477 wq = rcu_dereference(sk->sk_wq); 1478 if (!wq || test_and_clear_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags) == 0) 1479 goto out; 1480 1481 xs_run_error_worker(transport, XPRT_SOCK_WAKE_WRITE); 1482 sk->sk_write_pending--; 1483 out: 1484 rcu_read_unlock(); 1485 } 1486 1487 /** 1488 * xs_udp_write_space - callback invoked when socket buffer space 1489 * becomes available 1490 * @sk: socket whose state has changed 1491 * 1492 * Called when more output buffer space is available for this socket. 1493 * We try not to wake our writers until they can make "significant" 1494 * progress, otherwise we'll waste resources thrashing kernel_sendmsg 1495 * with a bunch of small requests. 1496 */ 1497 static void xs_udp_write_space(struct sock *sk) 1498 { 1499 read_lock_bh(&sk->sk_callback_lock); 1500 1501 /* from net/core/sock.c:sock_def_write_space */ 1502 if (sock_writeable(sk)) 1503 xs_write_space(sk); 1504 1505 read_unlock_bh(&sk->sk_callback_lock); 1506 } 1507 1508 /** 1509 * xs_tcp_write_space - callback invoked when socket buffer space 1510 * becomes available 1511 * @sk: socket whose state has changed 1512 * 1513 * Called when more output buffer space is available for this socket. 1514 * We try not to wake our writers until they can make "significant" 1515 * progress, otherwise we'll waste resources thrashing kernel_sendmsg 1516 * with a bunch of small requests. 1517 */ 1518 static void xs_tcp_write_space(struct sock *sk) 1519 { 1520 read_lock_bh(&sk->sk_callback_lock); 1521 1522 /* from net/core/stream.c:sk_stream_write_space */ 1523 if (sk_stream_is_writeable(sk)) 1524 xs_write_space(sk); 1525 1526 read_unlock_bh(&sk->sk_callback_lock); 1527 } 1528 1529 static void xs_udp_do_set_buffer_size(struct rpc_xprt *xprt) 1530 { 1531 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); 1532 struct sock *sk = transport->inet; 1533 1534 if (transport->rcvsize) { 1535 sk->sk_userlocks |= SOCK_RCVBUF_LOCK; 1536 sk->sk_rcvbuf = transport->rcvsize * xprt->max_reqs * 2; 1537 } 1538 if (transport->sndsize) { 1539 sk->sk_userlocks |= SOCK_SNDBUF_LOCK; 1540 sk->sk_sndbuf = transport->sndsize * xprt->max_reqs * 2; 1541 sk->sk_write_space(sk); 1542 } 1543 } 1544 1545 /** 1546 * xs_udp_set_buffer_size - set send and receive limits 1547 * @xprt: generic transport 1548 * @sndsize: requested size of send buffer, in bytes 1549 * @rcvsize: requested size of receive buffer, in bytes 1550 * 1551 * Set socket send and receive buffer size limits. 1552 */ 1553 static void xs_udp_set_buffer_size(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize) 1554 { 1555 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); 1556 1557 transport->sndsize = 0; 1558 if (sndsize) 1559 transport->sndsize = sndsize + 1024; 1560 transport->rcvsize = 0; 1561 if (rcvsize) 1562 transport->rcvsize = rcvsize + 1024; 1563 1564 xs_udp_do_set_buffer_size(xprt); 1565 } 1566 1567 /** 1568 * xs_udp_timer - called when a retransmit timeout occurs on a UDP transport 1569 * @xprt: controlling transport 1570 * @task: task that timed out 1571 * 1572 * Adjust the congestion window after a retransmit timeout has occurred. 1573 */ 1574 static void xs_udp_timer(struct rpc_xprt *xprt, struct rpc_task *task) 1575 { 1576 spin_lock(&xprt->transport_lock); 1577 xprt_adjust_cwnd(xprt, task, -ETIMEDOUT); 1578 spin_unlock(&xprt->transport_lock); 1579 } 1580 1581 static int xs_get_random_port(void) 1582 { 1583 unsigned short min = xprt_min_resvport, max = xprt_max_resvport; 1584 unsigned short range; 1585 unsigned short rand; 1586 1587 if (max < min) 1588 return -EADDRINUSE; 1589 range = max - min + 1; 1590 rand = (unsigned short) prandom_u32() % range; 1591 return rand + min; 1592 } 1593 1594 static unsigned short xs_sock_getport(struct socket *sock) 1595 { 1596 struct sockaddr_storage buf; 1597 unsigned short port = 0; 1598 1599 if (kernel_getsockname(sock, (struct sockaddr *)&buf) < 0) 1600 goto out; 1601 switch (buf.ss_family) { 1602 case AF_INET6: 1603 port = ntohs(((struct sockaddr_in6 *)&buf)->sin6_port); 1604 break; 1605 case AF_INET: 1606 port = ntohs(((struct sockaddr_in *)&buf)->sin_port); 1607 } 1608 out: 1609 return port; 1610 } 1611 1612 /** 1613 * xs_set_port - reset the port number in the remote endpoint address 1614 * @xprt: generic transport 1615 * @port: new port number 1616 * 1617 */ 1618 static void xs_set_port(struct rpc_xprt *xprt, unsigned short port) 1619 { 1620 dprintk("RPC: setting port for xprt %p to %u\n", xprt, port); 1621 1622 rpc_set_port(xs_addr(xprt), port); 1623 xs_update_peer_port(xprt); 1624 } 1625 1626 static void xs_set_srcport(struct sock_xprt *transport, struct socket *sock) 1627 { 1628 if (transport->srcport == 0 && transport->xprt.reuseport) 1629 transport->srcport = xs_sock_getport(sock); 1630 } 1631 1632 static int xs_get_srcport(struct sock_xprt *transport) 1633 { 1634 int port = transport->srcport; 1635 1636 if (port == 0 && transport->xprt.resvport) 1637 port = xs_get_random_port(); 1638 return port; 1639 } 1640 1641 static unsigned short xs_next_srcport(struct sock_xprt *transport, unsigned short port) 1642 { 1643 if (transport->srcport != 0) 1644 transport->srcport = 0; 1645 if (!transport->xprt.resvport) 1646 return 0; 1647 if (port <= xprt_min_resvport || port > xprt_max_resvport) 1648 return xprt_max_resvport; 1649 return --port; 1650 } 1651 static int xs_bind(struct sock_xprt *transport, struct socket *sock) 1652 { 1653 struct sockaddr_storage myaddr; 1654 int err, nloop = 0; 1655 int port = xs_get_srcport(transport); 1656 unsigned short last; 1657 1658 /* 1659 * If we are asking for any ephemeral port (i.e. port == 0 && 1660 * transport->xprt.resvport == 0), don't bind. Let the local 1661 * port selection happen implicitly when the socket is used 1662 * (for example at connect time). 1663 * 1664 * This ensures that we can continue to establish TCP 1665 * connections even when all local ephemeral ports are already 1666 * a part of some TCP connection. This makes no difference 1667 * for UDP sockets, but also doens't harm them. 1668 * 1669 * If we're asking for any reserved port (i.e. port == 0 && 1670 * transport->xprt.resvport == 1) xs_get_srcport above will 1671 * ensure that port is non-zero and we will bind as needed. 1672 */ 1673 if (port <= 0) 1674 return port; 1675 1676 memcpy(&myaddr, &transport->srcaddr, transport->xprt.addrlen); 1677 do { 1678 rpc_set_port((struct sockaddr *)&myaddr, port); 1679 err = kernel_bind(sock, (struct sockaddr *)&myaddr, 1680 transport->xprt.addrlen); 1681 if (err == 0) { 1682 transport->srcport = port; 1683 break; 1684 } 1685 last = port; 1686 port = xs_next_srcport(transport, port); 1687 if (port > last) 1688 nloop++; 1689 } while (err == -EADDRINUSE && nloop != 2); 1690 1691 if (myaddr.ss_family == AF_INET) 1692 dprintk("RPC: %s %pI4:%u: %s (%d)\n", __func__, 1693 &((struct sockaddr_in *)&myaddr)->sin_addr, 1694 port, err ? "failed" : "ok", err); 1695 else 1696 dprintk("RPC: %s %pI6:%u: %s (%d)\n", __func__, 1697 &((struct sockaddr_in6 *)&myaddr)->sin6_addr, 1698 port, err ? "failed" : "ok", err); 1699 return err; 1700 } 1701 1702 /* 1703 * We don't support autobind on AF_LOCAL sockets 1704 */ 1705 static void xs_local_rpcbind(struct rpc_task *task) 1706 { 1707 xprt_set_bound(task->tk_xprt); 1708 } 1709 1710 static void xs_local_set_port(struct rpc_xprt *xprt, unsigned short port) 1711 { 1712 } 1713 1714 #ifdef CONFIG_DEBUG_LOCK_ALLOC 1715 static struct lock_class_key xs_key[2]; 1716 static struct lock_class_key xs_slock_key[2]; 1717 1718 static inline void xs_reclassify_socketu(struct socket *sock) 1719 { 1720 struct sock *sk = sock->sk; 1721 1722 sock_lock_init_class_and_name(sk, "slock-AF_LOCAL-RPC", 1723 &xs_slock_key[1], "sk_lock-AF_LOCAL-RPC", &xs_key[1]); 1724 } 1725 1726 static inline void xs_reclassify_socket4(struct socket *sock) 1727 { 1728 struct sock *sk = sock->sk; 1729 1730 sock_lock_init_class_and_name(sk, "slock-AF_INET-RPC", 1731 &xs_slock_key[0], "sk_lock-AF_INET-RPC", &xs_key[0]); 1732 } 1733 1734 static inline void xs_reclassify_socket6(struct socket *sock) 1735 { 1736 struct sock *sk = sock->sk; 1737 1738 sock_lock_init_class_and_name(sk, "slock-AF_INET6-RPC", 1739 &xs_slock_key[1], "sk_lock-AF_INET6-RPC", &xs_key[1]); 1740 } 1741 1742 static inline void xs_reclassify_socket(int family, struct socket *sock) 1743 { 1744 if (WARN_ON_ONCE(!sock_allow_reclassification(sock->sk))) 1745 return; 1746 1747 switch (family) { 1748 case AF_LOCAL: 1749 xs_reclassify_socketu(sock); 1750 break; 1751 case AF_INET: 1752 xs_reclassify_socket4(sock); 1753 break; 1754 case AF_INET6: 1755 xs_reclassify_socket6(sock); 1756 break; 1757 } 1758 } 1759 #else 1760 static inline void xs_reclassify_socket(int family, struct socket *sock) 1761 { 1762 } 1763 #endif 1764 1765 static void xs_dummy_setup_socket(struct work_struct *work) 1766 { 1767 } 1768 1769 static struct socket *xs_create_sock(struct rpc_xprt *xprt, 1770 struct sock_xprt *transport, int family, int type, 1771 int protocol, bool reuseport) 1772 { 1773 struct file *filp; 1774 struct socket *sock; 1775 int err; 1776 1777 err = __sock_create(xprt->xprt_net, family, type, protocol, &sock, 1); 1778 if (err < 0) { 1779 dprintk("RPC: can't create %d transport socket (%d).\n", 1780 protocol, -err); 1781 goto out; 1782 } 1783 xs_reclassify_socket(family, sock); 1784 1785 if (reuseport) 1786 sock_set_reuseport(sock->sk); 1787 1788 err = xs_bind(transport, sock); 1789 if (err) { 1790 sock_release(sock); 1791 goto out; 1792 } 1793 1794 filp = sock_alloc_file(sock, O_NONBLOCK, NULL); 1795 if (IS_ERR(filp)) 1796 return ERR_CAST(filp); 1797 transport->file = filp; 1798 1799 return sock; 1800 out: 1801 return ERR_PTR(err); 1802 } 1803 1804 static int xs_local_finish_connecting(struct rpc_xprt *xprt, 1805 struct socket *sock) 1806 { 1807 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, 1808 xprt); 1809 1810 if (!transport->inet) { 1811 struct sock *sk = sock->sk; 1812 1813 write_lock_bh(&sk->sk_callback_lock); 1814 1815 xs_save_old_callbacks(transport, sk); 1816 1817 sk->sk_user_data = xprt; 1818 sk->sk_data_ready = xs_data_ready; 1819 sk->sk_write_space = xs_udp_write_space; 1820 sock_set_flag(sk, SOCK_FASYNC); 1821 sk->sk_error_report = xs_error_report; 1822 1823 xprt_clear_connected(xprt); 1824 1825 /* Reset to new socket */ 1826 transport->sock = sock; 1827 transport->inet = sk; 1828 1829 write_unlock_bh(&sk->sk_callback_lock); 1830 } 1831 1832 xs_stream_start_connect(transport); 1833 1834 return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0); 1835 } 1836 1837 /** 1838 * xs_local_setup_socket - create AF_LOCAL socket, connect to a local endpoint 1839 * @transport: socket transport to connect 1840 */ 1841 static int xs_local_setup_socket(struct sock_xprt *transport) 1842 { 1843 struct rpc_xprt *xprt = &transport->xprt; 1844 struct file *filp; 1845 struct socket *sock; 1846 int status; 1847 1848 status = __sock_create(xprt->xprt_net, AF_LOCAL, 1849 SOCK_STREAM, 0, &sock, 1); 1850 if (status < 0) { 1851 dprintk("RPC: can't create AF_LOCAL " 1852 "transport socket (%d).\n", -status); 1853 goto out; 1854 } 1855 xs_reclassify_socket(AF_LOCAL, sock); 1856 1857 filp = sock_alloc_file(sock, O_NONBLOCK, NULL); 1858 if (IS_ERR(filp)) { 1859 status = PTR_ERR(filp); 1860 goto out; 1861 } 1862 transport->file = filp; 1863 1864 dprintk("RPC: worker connecting xprt %p via AF_LOCAL to %s\n", 1865 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]); 1866 1867 status = xs_local_finish_connecting(xprt, sock); 1868 trace_rpc_socket_connect(xprt, sock, status); 1869 switch (status) { 1870 case 0: 1871 dprintk("RPC: xprt %p connected to %s\n", 1872 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]); 1873 xprt->stat.connect_count++; 1874 xprt->stat.connect_time += (long)jiffies - 1875 xprt->stat.connect_start; 1876 xprt_set_connected(xprt); 1877 case -ENOBUFS: 1878 break; 1879 case -ENOENT: 1880 dprintk("RPC: xprt %p: socket %s does not exist\n", 1881 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]); 1882 break; 1883 case -ECONNREFUSED: 1884 dprintk("RPC: xprt %p: connection refused for %s\n", 1885 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]); 1886 break; 1887 default: 1888 printk(KERN_ERR "%s: unhandled error (%d) connecting to %s\n", 1889 __func__, -status, 1890 xprt->address_strings[RPC_DISPLAY_ADDR]); 1891 } 1892 1893 out: 1894 xprt_clear_connecting(xprt); 1895 xprt_wake_pending_tasks(xprt, status); 1896 return status; 1897 } 1898 1899 static void xs_local_connect(struct rpc_xprt *xprt, struct rpc_task *task) 1900 { 1901 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); 1902 int ret; 1903 1904 if (RPC_IS_ASYNC(task)) { 1905 /* 1906 * We want the AF_LOCAL connect to be resolved in the 1907 * filesystem namespace of the process making the rpc 1908 * call. Thus we connect synchronously. 1909 * 1910 * If we want to support asynchronous AF_LOCAL calls, 1911 * we'll need to figure out how to pass a namespace to 1912 * connect. 1913 */ 1914 task->tk_rpc_status = -ENOTCONN; 1915 rpc_exit(task, -ENOTCONN); 1916 return; 1917 } 1918 ret = xs_local_setup_socket(transport); 1919 if (ret && !RPC_IS_SOFTCONN(task)) 1920 msleep_interruptible(15000); 1921 } 1922 1923 #if IS_ENABLED(CONFIG_SUNRPC_SWAP) 1924 /* 1925 * Note that this should be called with XPRT_LOCKED held (or when we otherwise 1926 * know that we have exclusive access to the socket), to guard against 1927 * races with xs_reset_transport. 1928 */ 1929 static void xs_set_memalloc(struct rpc_xprt *xprt) 1930 { 1931 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, 1932 xprt); 1933 1934 /* 1935 * If there's no sock, then we have nothing to set. The 1936 * reconnecting process will get it for us. 1937 */ 1938 if (!transport->inet) 1939 return; 1940 if (atomic_read(&xprt->swapper)) 1941 sk_set_memalloc(transport->inet); 1942 } 1943 1944 /** 1945 * xs_enable_swap - Tag this transport as being used for swap. 1946 * @xprt: transport to tag 1947 * 1948 * Take a reference to this transport on behalf of the rpc_clnt, and 1949 * optionally mark it for swapping if it wasn't already. 1950 */ 1951 static int 1952 xs_enable_swap(struct rpc_xprt *xprt) 1953 { 1954 struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt); 1955 1956 if (atomic_inc_return(&xprt->swapper) != 1) 1957 return 0; 1958 if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE)) 1959 return -ERESTARTSYS; 1960 if (xs->inet) 1961 sk_set_memalloc(xs->inet); 1962 xprt_release_xprt(xprt, NULL); 1963 return 0; 1964 } 1965 1966 /** 1967 * xs_disable_swap - Untag this transport as being used for swap. 1968 * @xprt: transport to tag 1969 * 1970 * Drop a "swapper" reference to this xprt on behalf of the rpc_clnt. If the 1971 * swapper refcount goes to 0, untag the socket as a memalloc socket. 1972 */ 1973 static void 1974 xs_disable_swap(struct rpc_xprt *xprt) 1975 { 1976 struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt); 1977 1978 if (!atomic_dec_and_test(&xprt->swapper)) 1979 return; 1980 if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE)) 1981 return; 1982 if (xs->inet) 1983 sk_clear_memalloc(xs->inet); 1984 xprt_release_xprt(xprt, NULL); 1985 } 1986 #else 1987 static void xs_set_memalloc(struct rpc_xprt *xprt) 1988 { 1989 } 1990 1991 static int 1992 xs_enable_swap(struct rpc_xprt *xprt) 1993 { 1994 return -EINVAL; 1995 } 1996 1997 static void 1998 xs_disable_swap(struct rpc_xprt *xprt) 1999 { 2000 } 2001 #endif 2002 2003 static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock) 2004 { 2005 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); 2006 2007 if (!transport->inet) { 2008 struct sock *sk = sock->sk; 2009 2010 write_lock_bh(&sk->sk_callback_lock); 2011 2012 xs_save_old_callbacks(transport, sk); 2013 2014 sk->sk_user_data = xprt; 2015 sk->sk_data_ready = xs_data_ready; 2016 sk->sk_write_space = xs_udp_write_space; 2017 sock_set_flag(sk, SOCK_FASYNC); 2018 2019 xprt_set_connected(xprt); 2020 2021 /* Reset to new socket */ 2022 transport->sock = sock; 2023 transport->inet = sk; 2024 2025 xs_set_memalloc(xprt); 2026 2027 write_unlock_bh(&sk->sk_callback_lock); 2028 } 2029 xs_udp_do_set_buffer_size(xprt); 2030 2031 xprt->stat.connect_start = jiffies; 2032 } 2033 2034 static void xs_udp_setup_socket(struct work_struct *work) 2035 { 2036 struct sock_xprt *transport = 2037 container_of(work, struct sock_xprt, connect_worker.work); 2038 struct rpc_xprt *xprt = &transport->xprt; 2039 struct socket *sock; 2040 int status = -EIO; 2041 2042 sock = xs_create_sock(xprt, transport, 2043 xs_addr(xprt)->sa_family, SOCK_DGRAM, 2044 IPPROTO_UDP, false); 2045 if (IS_ERR(sock)) 2046 goto out; 2047 2048 dprintk("RPC: worker connecting xprt %p via %s to " 2049 "%s (port %s)\n", xprt, 2050 xprt->address_strings[RPC_DISPLAY_PROTO], 2051 xprt->address_strings[RPC_DISPLAY_ADDR], 2052 xprt->address_strings[RPC_DISPLAY_PORT]); 2053 2054 xs_udp_finish_connecting(xprt, sock); 2055 trace_rpc_socket_connect(xprt, sock, 0); 2056 status = 0; 2057 out: 2058 xprt_clear_connecting(xprt); 2059 xprt_unlock_connect(xprt, transport); 2060 xprt_wake_pending_tasks(xprt, status); 2061 } 2062 2063 /** 2064 * xs_tcp_shutdown - gracefully shut down a TCP socket 2065 * @xprt: transport 2066 * 2067 * Initiates a graceful shutdown of the TCP socket by calling the 2068 * equivalent of shutdown(SHUT_RDWR); 2069 */ 2070 static void xs_tcp_shutdown(struct rpc_xprt *xprt) 2071 { 2072 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); 2073 struct socket *sock = transport->sock; 2074 int skst = transport->inet ? transport->inet->sk_state : TCP_CLOSE; 2075 2076 if (sock == NULL) 2077 return; 2078 switch (skst) { 2079 default: 2080 kernel_sock_shutdown(sock, SHUT_RDWR); 2081 trace_rpc_socket_shutdown(xprt, sock); 2082 break; 2083 case TCP_CLOSE: 2084 case TCP_TIME_WAIT: 2085 xs_reset_transport(transport); 2086 } 2087 } 2088 2089 static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt, 2090 struct socket *sock) 2091 { 2092 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); 2093 unsigned int keepidle; 2094 unsigned int keepcnt; 2095 unsigned int timeo; 2096 2097 spin_lock(&xprt->transport_lock); 2098 keepidle = DIV_ROUND_UP(xprt->timeout->to_initval, HZ); 2099 keepcnt = xprt->timeout->to_retries + 1; 2100 timeo = jiffies_to_msecs(xprt->timeout->to_initval) * 2101 (xprt->timeout->to_retries + 1); 2102 clear_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state); 2103 spin_unlock(&xprt->transport_lock); 2104 2105 /* TCP Keepalive options */ 2106 sock_set_keepalive(sock->sk); 2107 tcp_sock_set_keepidle(sock->sk, keepidle); 2108 tcp_sock_set_keepintvl(sock->sk, keepidle); 2109 tcp_sock_set_keepcnt(sock->sk, keepcnt); 2110 2111 /* TCP user timeout (see RFC5482) */ 2112 tcp_sock_set_user_timeout(sock->sk, timeo); 2113 } 2114 2115 static void xs_tcp_set_connect_timeout(struct rpc_xprt *xprt, 2116 unsigned long connect_timeout, 2117 unsigned long reconnect_timeout) 2118 { 2119 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); 2120 struct rpc_timeout to; 2121 unsigned long initval; 2122 2123 spin_lock(&xprt->transport_lock); 2124 if (reconnect_timeout < xprt->max_reconnect_timeout) 2125 xprt->max_reconnect_timeout = reconnect_timeout; 2126 if (connect_timeout < xprt->connect_timeout) { 2127 memcpy(&to, xprt->timeout, sizeof(to)); 2128 initval = DIV_ROUND_UP(connect_timeout, to.to_retries + 1); 2129 /* Arbitrary lower limit */ 2130 if (initval < XS_TCP_INIT_REEST_TO << 1) 2131 initval = XS_TCP_INIT_REEST_TO << 1; 2132 to.to_initval = initval; 2133 to.to_maxval = initval; 2134 memcpy(&transport->tcp_timeout, &to, 2135 sizeof(transport->tcp_timeout)); 2136 xprt->timeout = &transport->tcp_timeout; 2137 xprt->connect_timeout = connect_timeout; 2138 } 2139 set_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state); 2140 spin_unlock(&xprt->transport_lock); 2141 } 2142 2143 static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock) 2144 { 2145 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); 2146 int ret = -ENOTCONN; 2147 2148 if (!transport->inet) { 2149 struct sock *sk = sock->sk; 2150 2151 /* Avoid temporary address, they are bad for long-lived 2152 * connections such as NFS mounts. 2153 * RFC4941, section 3.6 suggests that: 2154 * Individual applications, which have specific 2155 * knowledge about the normal duration of connections, 2156 * MAY override this as appropriate. 2157 */ 2158 if (xs_addr(xprt)->sa_family == PF_INET6) { 2159 ip6_sock_set_addr_preferences(sk, 2160 IPV6_PREFER_SRC_PUBLIC); 2161 } 2162 2163 xs_tcp_set_socket_timeouts(xprt, sock); 2164 2165 write_lock_bh(&sk->sk_callback_lock); 2166 2167 xs_save_old_callbacks(transport, sk); 2168 2169 sk->sk_user_data = xprt; 2170 sk->sk_data_ready = xs_data_ready; 2171 sk->sk_state_change = xs_tcp_state_change; 2172 sk->sk_write_space = xs_tcp_write_space; 2173 sock_set_flag(sk, SOCK_FASYNC); 2174 sk->sk_error_report = xs_error_report; 2175 2176 /* socket options */ 2177 sock_reset_flag(sk, SOCK_LINGER); 2178 tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF; 2179 2180 xprt_clear_connected(xprt); 2181 2182 /* Reset to new socket */ 2183 transport->sock = sock; 2184 transport->inet = sk; 2185 2186 write_unlock_bh(&sk->sk_callback_lock); 2187 } 2188 2189 if (!xprt_bound(xprt)) 2190 goto out; 2191 2192 xs_set_memalloc(xprt); 2193 2194 xs_stream_start_connect(transport); 2195 2196 /* Tell the socket layer to start connecting... */ 2197 set_bit(XPRT_SOCK_CONNECTING, &transport->sock_state); 2198 ret = kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK); 2199 switch (ret) { 2200 case 0: 2201 xs_set_srcport(transport, sock); 2202 fallthrough; 2203 case -EINPROGRESS: 2204 /* SYN_SENT! */ 2205 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO) 2206 xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO; 2207 break; 2208 case -EADDRNOTAVAIL: 2209 /* Source port number is unavailable. Try a new one! */ 2210 transport->srcport = 0; 2211 } 2212 out: 2213 return ret; 2214 } 2215 2216 /** 2217 * xs_tcp_setup_socket - create a TCP socket and connect to a remote endpoint 2218 * @work: queued work item 2219 * 2220 * Invoked by a work queue tasklet. 2221 */ 2222 static void xs_tcp_setup_socket(struct work_struct *work) 2223 { 2224 struct sock_xprt *transport = 2225 container_of(work, struct sock_xprt, connect_worker.work); 2226 struct socket *sock = transport->sock; 2227 struct rpc_xprt *xprt = &transport->xprt; 2228 int status = -EIO; 2229 2230 if (!sock) { 2231 sock = xs_create_sock(xprt, transport, 2232 xs_addr(xprt)->sa_family, SOCK_STREAM, 2233 IPPROTO_TCP, true); 2234 if (IS_ERR(sock)) { 2235 status = PTR_ERR(sock); 2236 goto out; 2237 } 2238 } 2239 2240 dprintk("RPC: worker connecting xprt %p via %s to " 2241 "%s (port %s)\n", xprt, 2242 xprt->address_strings[RPC_DISPLAY_PROTO], 2243 xprt->address_strings[RPC_DISPLAY_ADDR], 2244 xprt->address_strings[RPC_DISPLAY_PORT]); 2245 2246 status = xs_tcp_finish_connecting(xprt, sock); 2247 trace_rpc_socket_connect(xprt, sock, status); 2248 dprintk("RPC: %p connect status %d connected %d sock state %d\n", 2249 xprt, -status, xprt_connected(xprt), 2250 sock->sk->sk_state); 2251 switch (status) { 2252 default: 2253 printk("%s: connect returned unhandled error %d\n", 2254 __func__, status); 2255 fallthrough; 2256 case -EADDRNOTAVAIL: 2257 /* We're probably in TIME_WAIT. Get rid of existing socket, 2258 * and retry 2259 */ 2260 xs_tcp_force_close(xprt); 2261 break; 2262 case 0: 2263 case -EINPROGRESS: 2264 case -EALREADY: 2265 xprt_unlock_connect(xprt, transport); 2266 return; 2267 case -EINVAL: 2268 /* Happens, for instance, if the user specified a link 2269 * local IPv6 address without a scope-id. 2270 */ 2271 case -ECONNREFUSED: 2272 case -ECONNRESET: 2273 case -ENETDOWN: 2274 case -ENETUNREACH: 2275 case -EHOSTUNREACH: 2276 case -EADDRINUSE: 2277 case -ENOBUFS: 2278 /* 2279 * xs_tcp_force_close() wakes tasks with -EIO. 2280 * We need to wake them first to ensure the 2281 * correct error code. 2282 */ 2283 xprt_wake_pending_tasks(xprt, status); 2284 xs_tcp_force_close(xprt); 2285 goto out; 2286 } 2287 status = -EAGAIN; 2288 out: 2289 xprt_clear_connecting(xprt); 2290 xprt_unlock_connect(xprt, transport); 2291 xprt_wake_pending_tasks(xprt, status); 2292 } 2293 2294 /** 2295 * xs_connect - connect a socket to a remote endpoint 2296 * @xprt: pointer to transport structure 2297 * @task: address of RPC task that manages state of connect request 2298 * 2299 * TCP: If the remote end dropped the connection, delay reconnecting. 2300 * 2301 * UDP socket connects are synchronous, but we use a work queue anyway 2302 * to guarantee that even unprivileged user processes can set up a 2303 * socket on a privileged port. 2304 * 2305 * If a UDP socket connect fails, the delay behavior here prevents 2306 * retry floods (hard mounts). 2307 */ 2308 static void xs_connect(struct rpc_xprt *xprt, struct rpc_task *task) 2309 { 2310 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); 2311 unsigned long delay = 0; 2312 2313 WARN_ON_ONCE(!xprt_lock_connect(xprt, task, transport)); 2314 2315 if (transport->sock != NULL) { 2316 dprintk("RPC: xs_connect delayed xprt %p for %lu " 2317 "seconds\n", 2318 xprt, xprt->reestablish_timeout / HZ); 2319 2320 /* Start by resetting any existing state */ 2321 xs_reset_transport(transport); 2322 2323 delay = xprt_reconnect_delay(xprt); 2324 xprt_reconnect_backoff(xprt, XS_TCP_INIT_REEST_TO); 2325 2326 } else 2327 dprintk("RPC: xs_connect scheduled xprt %p\n", xprt); 2328 2329 queue_delayed_work(xprtiod_workqueue, 2330 &transport->connect_worker, 2331 delay); 2332 } 2333 2334 static void xs_wake_disconnect(struct sock_xprt *transport) 2335 { 2336 if (test_and_clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state)) 2337 xs_tcp_force_close(&transport->xprt); 2338 } 2339 2340 static void xs_wake_write(struct sock_xprt *transport) 2341 { 2342 if (test_and_clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state)) 2343 xprt_write_space(&transport->xprt); 2344 } 2345 2346 static void xs_wake_error(struct sock_xprt *transport) 2347 { 2348 int sockerr; 2349 2350 if (!test_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state)) 2351 return; 2352 mutex_lock(&transport->recv_mutex); 2353 if (transport->sock == NULL) 2354 goto out; 2355 if (!test_and_clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state)) 2356 goto out; 2357 sockerr = xchg(&transport->xprt_err, 0); 2358 if (sockerr < 0) 2359 xprt_wake_pending_tasks(&transport->xprt, sockerr); 2360 out: 2361 mutex_unlock(&transport->recv_mutex); 2362 } 2363 2364 static void xs_wake_pending(struct sock_xprt *transport) 2365 { 2366 if (test_and_clear_bit(XPRT_SOCK_WAKE_PENDING, &transport->sock_state)) 2367 xprt_wake_pending_tasks(&transport->xprt, -EAGAIN); 2368 } 2369 2370 static void xs_error_handle(struct work_struct *work) 2371 { 2372 struct sock_xprt *transport = container_of(work, 2373 struct sock_xprt, error_worker); 2374 2375 xs_wake_disconnect(transport); 2376 xs_wake_write(transport); 2377 xs_wake_error(transport); 2378 xs_wake_pending(transport); 2379 } 2380 2381 /** 2382 * xs_local_print_stats - display AF_LOCAL socket-specifc stats 2383 * @xprt: rpc_xprt struct containing statistics 2384 * @seq: output file 2385 * 2386 */ 2387 static void xs_local_print_stats(struct rpc_xprt *xprt, struct seq_file *seq) 2388 { 2389 long idle_time = 0; 2390 2391 if (xprt_connected(xprt)) 2392 idle_time = (long)(jiffies - xprt->last_used) / HZ; 2393 2394 seq_printf(seq, "\txprt:\tlocal %lu %lu %lu %ld %lu %lu %lu " 2395 "%llu %llu %lu %llu %llu\n", 2396 xprt->stat.bind_count, 2397 xprt->stat.connect_count, 2398 xprt->stat.connect_time / HZ, 2399 idle_time, 2400 xprt->stat.sends, 2401 xprt->stat.recvs, 2402 xprt->stat.bad_xids, 2403 xprt->stat.req_u, 2404 xprt->stat.bklog_u, 2405 xprt->stat.max_slots, 2406 xprt->stat.sending_u, 2407 xprt->stat.pending_u); 2408 } 2409 2410 /** 2411 * xs_udp_print_stats - display UDP socket-specifc stats 2412 * @xprt: rpc_xprt struct containing statistics 2413 * @seq: output file 2414 * 2415 */ 2416 static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq) 2417 { 2418 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); 2419 2420 seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %llu %llu " 2421 "%lu %llu %llu\n", 2422 transport->srcport, 2423 xprt->stat.bind_count, 2424 xprt->stat.sends, 2425 xprt->stat.recvs, 2426 xprt->stat.bad_xids, 2427 xprt->stat.req_u, 2428 xprt->stat.bklog_u, 2429 xprt->stat.max_slots, 2430 xprt->stat.sending_u, 2431 xprt->stat.pending_u); 2432 } 2433 2434 /** 2435 * xs_tcp_print_stats - display TCP socket-specifc stats 2436 * @xprt: rpc_xprt struct containing statistics 2437 * @seq: output file 2438 * 2439 */ 2440 static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq) 2441 { 2442 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); 2443 long idle_time = 0; 2444 2445 if (xprt_connected(xprt)) 2446 idle_time = (long)(jiffies - xprt->last_used) / HZ; 2447 2448 seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu " 2449 "%llu %llu %lu %llu %llu\n", 2450 transport->srcport, 2451 xprt->stat.bind_count, 2452 xprt->stat.connect_count, 2453 xprt->stat.connect_time / HZ, 2454 idle_time, 2455 xprt->stat.sends, 2456 xprt->stat.recvs, 2457 xprt->stat.bad_xids, 2458 xprt->stat.req_u, 2459 xprt->stat.bklog_u, 2460 xprt->stat.max_slots, 2461 xprt->stat.sending_u, 2462 xprt->stat.pending_u); 2463 } 2464 2465 /* 2466 * Allocate a bunch of pages for a scratch buffer for the rpc code. The reason 2467 * we allocate pages instead doing a kmalloc like rpc_malloc is because we want 2468 * to use the server side send routines. 2469 */ 2470 static int bc_malloc(struct rpc_task *task) 2471 { 2472 struct rpc_rqst *rqst = task->tk_rqstp; 2473 size_t size = rqst->rq_callsize; 2474 struct page *page; 2475 struct rpc_buffer *buf; 2476 2477 if (size > PAGE_SIZE - sizeof(struct rpc_buffer)) { 2478 WARN_ONCE(1, "xprtsock: large bc buffer request (size %zu)\n", 2479 size); 2480 return -EINVAL; 2481 } 2482 2483 page = alloc_page(GFP_KERNEL); 2484 if (!page) 2485 return -ENOMEM; 2486 2487 buf = page_address(page); 2488 buf->len = PAGE_SIZE; 2489 2490 rqst->rq_buffer = buf->data; 2491 rqst->rq_rbuffer = (char *)rqst->rq_buffer + rqst->rq_callsize; 2492 return 0; 2493 } 2494 2495 /* 2496 * Free the space allocated in the bc_alloc routine 2497 */ 2498 static void bc_free(struct rpc_task *task) 2499 { 2500 void *buffer = task->tk_rqstp->rq_buffer; 2501 struct rpc_buffer *buf; 2502 2503 buf = container_of(buffer, struct rpc_buffer, data); 2504 free_page((unsigned long)buf); 2505 } 2506 2507 static int bc_sendto(struct rpc_rqst *req) 2508 { 2509 struct xdr_buf *xdr = &req->rq_snd_buf; 2510 struct sock_xprt *transport = 2511 container_of(req->rq_xprt, struct sock_xprt, xprt); 2512 struct msghdr msg = { 2513 .msg_flags = 0, 2514 }; 2515 rpc_fraghdr marker = cpu_to_be32(RPC_LAST_STREAM_FRAGMENT | 2516 (u32)xdr->len); 2517 unsigned int sent = 0; 2518 int err; 2519 2520 req->rq_xtime = ktime_get(); 2521 err = xprt_sock_sendmsg(transport->sock, &msg, xdr, 0, marker, &sent); 2522 xdr_free_bvec(xdr); 2523 if (err < 0 || sent != (xdr->len + sizeof(marker))) 2524 return -EAGAIN; 2525 return sent; 2526 } 2527 2528 /** 2529 * bc_send_request - Send a backchannel Call on a TCP socket 2530 * @req: rpc_rqst containing Call message to be sent 2531 * 2532 * xpt_mutex ensures @rqstp's whole message is written to the socket 2533 * without interruption. 2534 * 2535 * Return values: 2536 * %0 if the message was sent successfully 2537 * %ENOTCONN if the message was not sent 2538 */ 2539 static int bc_send_request(struct rpc_rqst *req) 2540 { 2541 struct svc_xprt *xprt; 2542 int len; 2543 2544 /* 2545 * Get the server socket associated with this callback xprt 2546 */ 2547 xprt = req->rq_xprt->bc_xprt; 2548 2549 /* 2550 * Grab the mutex to serialize data as the connection is shared 2551 * with the fore channel 2552 */ 2553 mutex_lock(&xprt->xpt_mutex); 2554 if (test_bit(XPT_DEAD, &xprt->xpt_flags)) 2555 len = -ENOTCONN; 2556 else 2557 len = bc_sendto(req); 2558 mutex_unlock(&xprt->xpt_mutex); 2559 2560 if (len > 0) 2561 len = 0; 2562 2563 return len; 2564 } 2565 2566 /* 2567 * The close routine. Since this is client initiated, we do nothing 2568 */ 2569 2570 static void bc_close(struct rpc_xprt *xprt) 2571 { 2572 xprt_disconnect_done(xprt); 2573 } 2574 2575 /* 2576 * The xprt destroy routine. Again, because this connection is client 2577 * initiated, we do nothing 2578 */ 2579 2580 static void bc_destroy(struct rpc_xprt *xprt) 2581 { 2582 dprintk("RPC: bc_destroy xprt %p\n", xprt); 2583 2584 xs_xprt_free(xprt); 2585 module_put(THIS_MODULE); 2586 } 2587 2588 static const struct rpc_xprt_ops xs_local_ops = { 2589 .reserve_xprt = xprt_reserve_xprt, 2590 .release_xprt = xprt_release_xprt, 2591 .alloc_slot = xprt_alloc_slot, 2592 .free_slot = xprt_free_slot, 2593 .rpcbind = xs_local_rpcbind, 2594 .set_port = xs_local_set_port, 2595 .connect = xs_local_connect, 2596 .buf_alloc = rpc_malloc, 2597 .buf_free = rpc_free, 2598 .prepare_request = xs_stream_prepare_request, 2599 .send_request = xs_local_send_request, 2600 .wait_for_reply_request = xprt_wait_for_reply_request_def, 2601 .close = xs_close, 2602 .destroy = xs_destroy, 2603 .print_stats = xs_local_print_stats, 2604 .enable_swap = xs_enable_swap, 2605 .disable_swap = xs_disable_swap, 2606 }; 2607 2608 static const struct rpc_xprt_ops xs_udp_ops = { 2609 .set_buffer_size = xs_udp_set_buffer_size, 2610 .reserve_xprt = xprt_reserve_xprt_cong, 2611 .release_xprt = xprt_release_xprt_cong, 2612 .alloc_slot = xprt_alloc_slot, 2613 .free_slot = xprt_free_slot, 2614 .rpcbind = rpcb_getport_async, 2615 .set_port = xs_set_port, 2616 .connect = xs_connect, 2617 .buf_alloc = rpc_malloc, 2618 .buf_free = rpc_free, 2619 .send_request = xs_udp_send_request, 2620 .wait_for_reply_request = xprt_wait_for_reply_request_rtt, 2621 .timer = xs_udp_timer, 2622 .release_request = xprt_release_rqst_cong, 2623 .close = xs_close, 2624 .destroy = xs_destroy, 2625 .print_stats = xs_udp_print_stats, 2626 .enable_swap = xs_enable_swap, 2627 .disable_swap = xs_disable_swap, 2628 .inject_disconnect = xs_inject_disconnect, 2629 }; 2630 2631 static const struct rpc_xprt_ops xs_tcp_ops = { 2632 .reserve_xprt = xprt_reserve_xprt, 2633 .release_xprt = xprt_release_xprt, 2634 .alloc_slot = xprt_alloc_slot, 2635 .free_slot = xprt_free_slot, 2636 .rpcbind = rpcb_getport_async, 2637 .set_port = xs_set_port, 2638 .connect = xs_connect, 2639 .buf_alloc = rpc_malloc, 2640 .buf_free = rpc_free, 2641 .prepare_request = xs_stream_prepare_request, 2642 .send_request = xs_tcp_send_request, 2643 .wait_for_reply_request = xprt_wait_for_reply_request_def, 2644 .close = xs_tcp_shutdown, 2645 .destroy = xs_destroy, 2646 .set_connect_timeout = xs_tcp_set_connect_timeout, 2647 .print_stats = xs_tcp_print_stats, 2648 .enable_swap = xs_enable_swap, 2649 .disable_swap = xs_disable_swap, 2650 .inject_disconnect = xs_inject_disconnect, 2651 #ifdef CONFIG_SUNRPC_BACKCHANNEL 2652 .bc_setup = xprt_setup_bc, 2653 .bc_maxpayload = xs_tcp_bc_maxpayload, 2654 .bc_num_slots = xprt_bc_max_slots, 2655 .bc_free_rqst = xprt_free_bc_rqst, 2656 .bc_destroy = xprt_destroy_bc, 2657 #endif 2658 }; 2659 2660 /* 2661 * The rpc_xprt_ops for the server backchannel 2662 */ 2663 2664 static const struct rpc_xprt_ops bc_tcp_ops = { 2665 .reserve_xprt = xprt_reserve_xprt, 2666 .release_xprt = xprt_release_xprt, 2667 .alloc_slot = xprt_alloc_slot, 2668 .free_slot = xprt_free_slot, 2669 .buf_alloc = bc_malloc, 2670 .buf_free = bc_free, 2671 .send_request = bc_send_request, 2672 .wait_for_reply_request = xprt_wait_for_reply_request_def, 2673 .close = bc_close, 2674 .destroy = bc_destroy, 2675 .print_stats = xs_tcp_print_stats, 2676 .enable_swap = xs_enable_swap, 2677 .disable_swap = xs_disable_swap, 2678 .inject_disconnect = xs_inject_disconnect, 2679 }; 2680 2681 static int xs_init_anyaddr(const int family, struct sockaddr *sap) 2682 { 2683 static const struct sockaddr_in sin = { 2684 .sin_family = AF_INET, 2685 .sin_addr.s_addr = htonl(INADDR_ANY), 2686 }; 2687 static const struct sockaddr_in6 sin6 = { 2688 .sin6_family = AF_INET6, 2689 .sin6_addr = IN6ADDR_ANY_INIT, 2690 }; 2691 2692 switch (family) { 2693 case AF_LOCAL: 2694 break; 2695 case AF_INET: 2696 memcpy(sap, &sin, sizeof(sin)); 2697 break; 2698 case AF_INET6: 2699 memcpy(sap, &sin6, sizeof(sin6)); 2700 break; 2701 default: 2702 dprintk("RPC: %s: Bad address family\n", __func__); 2703 return -EAFNOSUPPORT; 2704 } 2705 return 0; 2706 } 2707 2708 static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args, 2709 unsigned int slot_table_size, 2710 unsigned int max_slot_table_size) 2711 { 2712 struct rpc_xprt *xprt; 2713 struct sock_xprt *new; 2714 2715 if (args->addrlen > sizeof(xprt->addr)) { 2716 dprintk("RPC: xs_setup_xprt: address too large\n"); 2717 return ERR_PTR(-EBADF); 2718 } 2719 2720 xprt = xprt_alloc(args->net, sizeof(*new), slot_table_size, 2721 max_slot_table_size); 2722 if (xprt == NULL) { 2723 dprintk("RPC: xs_setup_xprt: couldn't allocate " 2724 "rpc_xprt\n"); 2725 return ERR_PTR(-ENOMEM); 2726 } 2727 2728 new = container_of(xprt, struct sock_xprt, xprt); 2729 mutex_init(&new->recv_mutex); 2730 memcpy(&xprt->addr, args->dstaddr, args->addrlen); 2731 xprt->addrlen = args->addrlen; 2732 if (args->srcaddr) 2733 memcpy(&new->srcaddr, args->srcaddr, args->addrlen); 2734 else { 2735 int err; 2736 err = xs_init_anyaddr(args->dstaddr->sa_family, 2737 (struct sockaddr *)&new->srcaddr); 2738 if (err != 0) { 2739 xprt_free(xprt); 2740 return ERR_PTR(err); 2741 } 2742 } 2743 2744 return xprt; 2745 } 2746 2747 static const struct rpc_timeout xs_local_default_timeout = { 2748 .to_initval = 10 * HZ, 2749 .to_maxval = 10 * HZ, 2750 .to_retries = 2, 2751 }; 2752 2753 /** 2754 * xs_setup_local - Set up transport to use an AF_LOCAL socket 2755 * @args: rpc transport creation arguments 2756 * 2757 * AF_LOCAL is a "tpi_cots_ord" transport, just like TCP 2758 */ 2759 static struct rpc_xprt *xs_setup_local(struct xprt_create *args) 2760 { 2761 struct sockaddr_un *sun = (struct sockaddr_un *)args->dstaddr; 2762 struct sock_xprt *transport; 2763 struct rpc_xprt *xprt; 2764 struct rpc_xprt *ret; 2765 2766 xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries, 2767 xprt_max_tcp_slot_table_entries); 2768 if (IS_ERR(xprt)) 2769 return xprt; 2770 transport = container_of(xprt, struct sock_xprt, xprt); 2771 2772 xprt->prot = 0; 2773 xprt->max_payload = RPC_MAX_FRAGMENT_SIZE; 2774 2775 xprt->bind_timeout = XS_BIND_TO; 2776 xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO; 2777 xprt->idle_timeout = XS_IDLE_DISC_TO; 2778 2779 xprt->ops = &xs_local_ops; 2780 xprt->timeout = &xs_local_default_timeout; 2781 2782 INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn); 2783 INIT_WORK(&transport->error_worker, xs_error_handle); 2784 INIT_DELAYED_WORK(&transport->connect_worker, xs_dummy_setup_socket); 2785 2786 switch (sun->sun_family) { 2787 case AF_LOCAL: 2788 if (sun->sun_path[0] != '/') { 2789 dprintk("RPC: bad AF_LOCAL address: %s\n", 2790 sun->sun_path); 2791 ret = ERR_PTR(-EINVAL); 2792 goto out_err; 2793 } 2794 xprt_set_bound(xprt); 2795 xs_format_peer_addresses(xprt, "local", RPCBIND_NETID_LOCAL); 2796 ret = ERR_PTR(xs_local_setup_socket(transport)); 2797 if (ret) 2798 goto out_err; 2799 break; 2800 default: 2801 ret = ERR_PTR(-EAFNOSUPPORT); 2802 goto out_err; 2803 } 2804 2805 dprintk("RPC: set up xprt to %s via AF_LOCAL\n", 2806 xprt->address_strings[RPC_DISPLAY_ADDR]); 2807 2808 if (try_module_get(THIS_MODULE)) 2809 return xprt; 2810 ret = ERR_PTR(-EINVAL); 2811 out_err: 2812 xs_xprt_free(xprt); 2813 return ret; 2814 } 2815 2816 static const struct rpc_timeout xs_udp_default_timeout = { 2817 .to_initval = 5 * HZ, 2818 .to_maxval = 30 * HZ, 2819 .to_increment = 5 * HZ, 2820 .to_retries = 5, 2821 }; 2822 2823 /** 2824 * xs_setup_udp - Set up transport to use a UDP socket 2825 * @args: rpc transport creation arguments 2826 * 2827 */ 2828 static struct rpc_xprt *xs_setup_udp(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 2835 xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries, 2836 xprt_udp_slot_table_entries); 2837 if (IS_ERR(xprt)) 2838 return xprt; 2839 transport = container_of(xprt, struct sock_xprt, xprt); 2840 2841 xprt->prot = IPPROTO_UDP; 2842 /* XXX: header size can vary due to auth type, IPv6, etc. */ 2843 xprt->max_payload = (1U << 16) - (MAX_HEADER << 3); 2844 2845 xprt->bind_timeout = XS_BIND_TO; 2846 xprt->reestablish_timeout = XS_UDP_REEST_TO; 2847 xprt->idle_timeout = XS_IDLE_DISC_TO; 2848 2849 xprt->ops = &xs_udp_ops; 2850 2851 xprt->timeout = &xs_udp_default_timeout; 2852 2853 INIT_WORK(&transport->recv_worker, xs_udp_data_receive_workfn); 2854 INIT_WORK(&transport->error_worker, xs_error_handle); 2855 INIT_DELAYED_WORK(&transport->connect_worker, xs_udp_setup_socket); 2856 2857 switch (addr->sa_family) { 2858 case AF_INET: 2859 if (((struct sockaddr_in *)addr)->sin_port != htons(0)) 2860 xprt_set_bound(xprt); 2861 2862 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP); 2863 break; 2864 case AF_INET6: 2865 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0)) 2866 xprt_set_bound(xprt); 2867 2868 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP6); 2869 break; 2870 default: 2871 ret = ERR_PTR(-EAFNOSUPPORT); 2872 goto out_err; 2873 } 2874 2875 if (xprt_bound(xprt)) 2876 dprintk("RPC: set up xprt to %s (port %s) via %s\n", 2877 xprt->address_strings[RPC_DISPLAY_ADDR], 2878 xprt->address_strings[RPC_DISPLAY_PORT], 2879 xprt->address_strings[RPC_DISPLAY_PROTO]); 2880 else 2881 dprintk("RPC: set up xprt to %s (autobind) via %s\n", 2882 xprt->address_strings[RPC_DISPLAY_ADDR], 2883 xprt->address_strings[RPC_DISPLAY_PROTO]); 2884 2885 if (try_module_get(THIS_MODULE)) 2886 return xprt; 2887 ret = ERR_PTR(-EINVAL); 2888 out_err: 2889 xs_xprt_free(xprt); 2890 return ret; 2891 } 2892 2893 static const struct rpc_timeout xs_tcp_default_timeout = { 2894 .to_initval = 60 * HZ, 2895 .to_maxval = 60 * HZ, 2896 .to_retries = 2, 2897 }; 2898 2899 /** 2900 * xs_setup_tcp - Set up transport to use a TCP socket 2901 * @args: rpc transport creation arguments 2902 * 2903 */ 2904 static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args) 2905 { 2906 struct sockaddr *addr = args->dstaddr; 2907 struct rpc_xprt *xprt; 2908 struct sock_xprt *transport; 2909 struct rpc_xprt *ret; 2910 unsigned int max_slot_table_size = xprt_max_tcp_slot_table_entries; 2911 2912 if (args->flags & XPRT_CREATE_INFINITE_SLOTS) 2913 max_slot_table_size = RPC_MAX_SLOT_TABLE_LIMIT; 2914 2915 xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries, 2916 max_slot_table_size); 2917 if (IS_ERR(xprt)) 2918 return xprt; 2919 transport = container_of(xprt, struct sock_xprt, xprt); 2920 2921 xprt->prot = IPPROTO_TCP; 2922 xprt->max_payload = RPC_MAX_FRAGMENT_SIZE; 2923 2924 xprt->bind_timeout = XS_BIND_TO; 2925 xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO; 2926 xprt->idle_timeout = XS_IDLE_DISC_TO; 2927 2928 xprt->ops = &xs_tcp_ops; 2929 xprt->timeout = &xs_tcp_default_timeout; 2930 2931 xprt->max_reconnect_timeout = xprt->timeout->to_maxval; 2932 xprt->connect_timeout = xprt->timeout->to_initval * 2933 (xprt->timeout->to_retries + 1); 2934 2935 INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn); 2936 INIT_WORK(&transport->error_worker, xs_error_handle); 2937 INIT_DELAYED_WORK(&transport->connect_worker, xs_tcp_setup_socket); 2938 2939 switch (addr->sa_family) { 2940 case AF_INET: 2941 if (((struct sockaddr_in *)addr)->sin_port != htons(0)) 2942 xprt_set_bound(xprt); 2943 2944 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP); 2945 break; 2946 case AF_INET6: 2947 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0)) 2948 xprt_set_bound(xprt); 2949 2950 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6); 2951 break; 2952 default: 2953 ret = ERR_PTR(-EAFNOSUPPORT); 2954 goto out_err; 2955 } 2956 2957 if (xprt_bound(xprt)) 2958 dprintk("RPC: set up xprt to %s (port %s) via %s\n", 2959 xprt->address_strings[RPC_DISPLAY_ADDR], 2960 xprt->address_strings[RPC_DISPLAY_PORT], 2961 xprt->address_strings[RPC_DISPLAY_PROTO]); 2962 else 2963 dprintk("RPC: set up xprt to %s (autobind) via %s\n", 2964 xprt->address_strings[RPC_DISPLAY_ADDR], 2965 xprt->address_strings[RPC_DISPLAY_PROTO]); 2966 2967 if (try_module_get(THIS_MODULE)) 2968 return xprt; 2969 ret = ERR_PTR(-EINVAL); 2970 out_err: 2971 xs_xprt_free(xprt); 2972 return ret; 2973 } 2974 2975 /** 2976 * xs_setup_bc_tcp - Set up transport to use a TCP backchannel socket 2977 * @args: rpc transport creation arguments 2978 * 2979 */ 2980 static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args) 2981 { 2982 struct sockaddr *addr = args->dstaddr; 2983 struct rpc_xprt *xprt; 2984 struct sock_xprt *transport; 2985 struct svc_sock *bc_sock; 2986 struct rpc_xprt *ret; 2987 2988 xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries, 2989 xprt_tcp_slot_table_entries); 2990 if (IS_ERR(xprt)) 2991 return xprt; 2992 transport = container_of(xprt, struct sock_xprt, xprt); 2993 2994 xprt->prot = IPPROTO_TCP; 2995 xprt->max_payload = RPC_MAX_FRAGMENT_SIZE; 2996 xprt->timeout = &xs_tcp_default_timeout; 2997 2998 /* backchannel */ 2999 xprt_set_bound(xprt); 3000 xprt->bind_timeout = 0; 3001 xprt->reestablish_timeout = 0; 3002 xprt->idle_timeout = 0; 3003 3004 xprt->ops = &bc_tcp_ops; 3005 3006 switch (addr->sa_family) { 3007 case AF_INET: 3008 xs_format_peer_addresses(xprt, "tcp", 3009 RPCBIND_NETID_TCP); 3010 break; 3011 case AF_INET6: 3012 xs_format_peer_addresses(xprt, "tcp", 3013 RPCBIND_NETID_TCP6); 3014 break; 3015 default: 3016 ret = ERR_PTR(-EAFNOSUPPORT); 3017 goto out_err; 3018 } 3019 3020 dprintk("RPC: set up xprt to %s (port %s) via %s\n", 3021 xprt->address_strings[RPC_DISPLAY_ADDR], 3022 xprt->address_strings[RPC_DISPLAY_PORT], 3023 xprt->address_strings[RPC_DISPLAY_PROTO]); 3024 3025 /* 3026 * Once we've associated a backchannel xprt with a connection, 3027 * we want to keep it around as long as the connection lasts, 3028 * in case we need to start using it for a backchannel again; 3029 * this reference won't be dropped until bc_xprt is destroyed. 3030 */ 3031 xprt_get(xprt); 3032 args->bc_xprt->xpt_bc_xprt = xprt; 3033 xprt->bc_xprt = args->bc_xprt; 3034 bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt); 3035 transport->sock = bc_sock->sk_sock; 3036 transport->inet = bc_sock->sk_sk; 3037 3038 /* 3039 * Since we don't want connections for the backchannel, we set 3040 * the xprt status to connected 3041 */ 3042 xprt_set_connected(xprt); 3043 3044 if (try_module_get(THIS_MODULE)) 3045 return xprt; 3046 3047 args->bc_xprt->xpt_bc_xprt = NULL; 3048 args->bc_xprt->xpt_bc_xps = NULL; 3049 xprt_put(xprt); 3050 ret = ERR_PTR(-EINVAL); 3051 out_err: 3052 xs_xprt_free(xprt); 3053 return ret; 3054 } 3055 3056 static struct xprt_class xs_local_transport = { 3057 .list = LIST_HEAD_INIT(xs_local_transport.list), 3058 .name = "named UNIX socket", 3059 .owner = THIS_MODULE, 3060 .ident = XPRT_TRANSPORT_LOCAL, 3061 .setup = xs_setup_local, 3062 }; 3063 3064 static struct xprt_class xs_udp_transport = { 3065 .list = LIST_HEAD_INIT(xs_udp_transport.list), 3066 .name = "udp", 3067 .owner = THIS_MODULE, 3068 .ident = XPRT_TRANSPORT_UDP, 3069 .setup = xs_setup_udp, 3070 }; 3071 3072 static struct xprt_class xs_tcp_transport = { 3073 .list = LIST_HEAD_INIT(xs_tcp_transport.list), 3074 .name = "tcp", 3075 .owner = THIS_MODULE, 3076 .ident = XPRT_TRANSPORT_TCP, 3077 .setup = xs_setup_tcp, 3078 }; 3079 3080 static struct xprt_class xs_bc_tcp_transport = { 3081 .list = LIST_HEAD_INIT(xs_bc_tcp_transport.list), 3082 .name = "tcp NFSv4.1 backchannel", 3083 .owner = THIS_MODULE, 3084 .ident = XPRT_TRANSPORT_BC_TCP, 3085 .setup = xs_setup_bc_tcp, 3086 }; 3087 3088 /** 3089 * init_socket_xprt - set up xprtsock's sysctls, register with RPC client 3090 * 3091 */ 3092 int init_socket_xprt(void) 3093 { 3094 if (!sunrpc_table_header) 3095 sunrpc_table_header = register_sysctl_table(sunrpc_table); 3096 3097 xprt_register_transport(&xs_local_transport); 3098 xprt_register_transport(&xs_udp_transport); 3099 xprt_register_transport(&xs_tcp_transport); 3100 xprt_register_transport(&xs_bc_tcp_transport); 3101 3102 return 0; 3103 } 3104 3105 /** 3106 * cleanup_socket_xprt - remove xprtsock's sysctls, unregister 3107 * 3108 */ 3109 void cleanup_socket_xprt(void) 3110 { 3111 if (sunrpc_table_header) { 3112 unregister_sysctl_table(sunrpc_table_header); 3113 sunrpc_table_header = NULL; 3114 } 3115 3116 xprt_unregister_transport(&xs_local_transport); 3117 xprt_unregister_transport(&xs_udp_transport); 3118 xprt_unregister_transport(&xs_tcp_transport); 3119 xprt_unregister_transport(&xs_bc_tcp_transport); 3120 } 3121 3122 static int param_set_uint_minmax(const char *val, 3123 const struct kernel_param *kp, 3124 unsigned int min, unsigned int max) 3125 { 3126 unsigned int num; 3127 int ret; 3128 3129 if (!val) 3130 return -EINVAL; 3131 ret = kstrtouint(val, 0, &num); 3132 if (ret) 3133 return ret; 3134 if (num < min || num > max) 3135 return -EINVAL; 3136 *((unsigned int *)kp->arg) = num; 3137 return 0; 3138 } 3139 3140 static int param_set_portnr(const char *val, const struct kernel_param *kp) 3141 { 3142 return param_set_uint_minmax(val, kp, 3143 RPC_MIN_RESVPORT, 3144 RPC_MAX_RESVPORT); 3145 } 3146 3147 static const struct kernel_param_ops param_ops_portnr = { 3148 .set = param_set_portnr, 3149 .get = param_get_uint, 3150 }; 3151 3152 #define param_check_portnr(name, p) \ 3153 __param_check(name, p, unsigned int); 3154 3155 module_param_named(min_resvport, xprt_min_resvport, portnr, 0644); 3156 module_param_named(max_resvport, xprt_max_resvport, portnr, 0644); 3157 3158 static int param_set_slot_table_size(const char *val, 3159 const struct kernel_param *kp) 3160 { 3161 return param_set_uint_minmax(val, kp, 3162 RPC_MIN_SLOT_TABLE, 3163 RPC_MAX_SLOT_TABLE); 3164 } 3165 3166 static const struct kernel_param_ops param_ops_slot_table_size = { 3167 .set = param_set_slot_table_size, 3168 .get = param_get_uint, 3169 }; 3170 3171 #define param_check_slot_table_size(name, p) \ 3172 __param_check(name, p, unsigned int); 3173 3174 static int param_set_max_slot_table_size(const char *val, 3175 const struct kernel_param *kp) 3176 { 3177 return param_set_uint_minmax(val, kp, 3178 RPC_MIN_SLOT_TABLE, 3179 RPC_MAX_SLOT_TABLE_LIMIT); 3180 } 3181 3182 static const struct kernel_param_ops param_ops_max_slot_table_size = { 3183 .set = param_set_max_slot_table_size, 3184 .get = param_get_uint, 3185 }; 3186 3187 #define param_check_max_slot_table_size(name, p) \ 3188 __param_check(name, p, unsigned int); 3189 3190 module_param_named(tcp_slot_table_entries, xprt_tcp_slot_table_entries, 3191 slot_table_size, 0644); 3192 module_param_named(tcp_max_slot_table_entries, xprt_max_tcp_slot_table_entries, 3193 max_slot_table_size, 0644); 3194 module_param_named(udp_slot_table_entries, xprt_udp_slot_table_entries, 3195 slot_table_size, 0644); 3196