1 /* 2 * linux/net/sunrpc/svc_xprt.c 3 * 4 * Author: Tom Tucker <tom@opengridcomputing.com> 5 */ 6 7 #include <linux/sched.h> 8 #include <linux/errno.h> 9 #include <linux/freezer.h> 10 #include <linux/kthread.h> 11 #include <linux/slab.h> 12 #include <net/sock.h> 13 #include <linux/sunrpc/stats.h> 14 #include <linux/sunrpc/svc_xprt.h> 15 #include <linux/sunrpc/svcsock.h> 16 #include <linux/sunrpc/xprt.h> 17 #include <linux/module.h> 18 19 #define RPCDBG_FACILITY RPCDBG_SVCXPRT 20 21 static struct svc_deferred_req *svc_deferred_dequeue(struct svc_xprt *xprt); 22 static int svc_deferred_recv(struct svc_rqst *rqstp); 23 static struct cache_deferred_req *svc_defer(struct cache_req *req); 24 static void svc_age_temp_xprts(unsigned long closure); 25 static void svc_delete_xprt(struct svc_xprt *xprt); 26 27 /* apparently the "standard" is that clients close 28 * idle connections after 5 minutes, servers after 29 * 6 minutes 30 * http://www.connectathon.org/talks96/nfstcp.pdf 31 */ 32 static int svc_conn_age_period = 6*60; 33 34 /* List of registered transport classes */ 35 static DEFINE_SPINLOCK(svc_xprt_class_lock); 36 static LIST_HEAD(svc_xprt_class_list); 37 38 /* SMP locking strategy: 39 * 40 * svc_pool->sp_lock protects most of the fields of that pool. 41 * svc_serv->sv_lock protects sv_tempsocks, sv_permsocks, sv_tmpcnt. 42 * when both need to be taken (rare), svc_serv->sv_lock is first. 43 * BKL protects svc_serv->sv_nrthread. 44 * svc_sock->sk_lock protects the svc_sock->sk_deferred list 45 * and the ->sk_info_authunix cache. 46 * 47 * The XPT_BUSY bit in xprt->xpt_flags prevents a transport being 48 * enqueued multiply. During normal transport processing this bit 49 * is set by svc_xprt_enqueue and cleared by svc_xprt_received. 50 * Providers should not manipulate this bit directly. 51 * 52 * Some flags can be set to certain values at any time 53 * providing that certain rules are followed: 54 * 55 * XPT_CONN, XPT_DATA: 56 * - Can be set or cleared at any time. 57 * - After a set, svc_xprt_enqueue must be called to enqueue 58 * the transport for processing. 59 * - After a clear, the transport must be read/accepted. 60 * If this succeeds, it must be set again. 61 * XPT_CLOSE: 62 * - Can set at any time. It is never cleared. 63 * XPT_DEAD: 64 * - Can only be set while XPT_BUSY is held which ensures 65 * that no other thread will be using the transport or will 66 * try to set XPT_DEAD. 67 */ 68 69 int svc_reg_xprt_class(struct svc_xprt_class *xcl) 70 { 71 struct svc_xprt_class *cl; 72 int res = -EEXIST; 73 74 dprintk("svc: Adding svc transport class '%s'\n", xcl->xcl_name); 75 76 INIT_LIST_HEAD(&xcl->xcl_list); 77 spin_lock(&svc_xprt_class_lock); 78 /* Make sure there isn't already a class with the same name */ 79 list_for_each_entry(cl, &svc_xprt_class_list, xcl_list) { 80 if (strcmp(xcl->xcl_name, cl->xcl_name) == 0) 81 goto out; 82 } 83 list_add_tail(&xcl->xcl_list, &svc_xprt_class_list); 84 res = 0; 85 out: 86 spin_unlock(&svc_xprt_class_lock); 87 return res; 88 } 89 EXPORT_SYMBOL_GPL(svc_reg_xprt_class); 90 91 void svc_unreg_xprt_class(struct svc_xprt_class *xcl) 92 { 93 dprintk("svc: Removing svc transport class '%s'\n", xcl->xcl_name); 94 spin_lock(&svc_xprt_class_lock); 95 list_del_init(&xcl->xcl_list); 96 spin_unlock(&svc_xprt_class_lock); 97 } 98 EXPORT_SYMBOL_GPL(svc_unreg_xprt_class); 99 100 /* 101 * Format the transport list for printing 102 */ 103 int svc_print_xprts(char *buf, int maxlen) 104 { 105 struct svc_xprt_class *xcl; 106 char tmpstr[80]; 107 int len = 0; 108 buf[0] = '\0'; 109 110 spin_lock(&svc_xprt_class_lock); 111 list_for_each_entry(xcl, &svc_xprt_class_list, xcl_list) { 112 int slen; 113 114 sprintf(tmpstr, "%s %d\n", xcl->xcl_name, xcl->xcl_max_payload); 115 slen = strlen(tmpstr); 116 if (len + slen > maxlen) 117 break; 118 len += slen; 119 strcat(buf, tmpstr); 120 } 121 spin_unlock(&svc_xprt_class_lock); 122 123 return len; 124 } 125 126 static void svc_xprt_free(struct kref *kref) 127 { 128 struct svc_xprt *xprt = 129 container_of(kref, struct svc_xprt, xpt_ref); 130 struct module *owner = xprt->xpt_class->xcl_owner; 131 if (test_bit(XPT_CACHE_AUTH, &xprt->xpt_flags)) 132 svcauth_unix_info_release(xprt); 133 put_net(xprt->xpt_net); 134 /* See comment on corresponding get in xs_setup_bc_tcp(): */ 135 if (xprt->xpt_bc_xprt) 136 xprt_put(xprt->xpt_bc_xprt); 137 xprt->xpt_ops->xpo_free(xprt); 138 module_put(owner); 139 } 140 141 void svc_xprt_put(struct svc_xprt *xprt) 142 { 143 kref_put(&xprt->xpt_ref, svc_xprt_free); 144 } 145 EXPORT_SYMBOL_GPL(svc_xprt_put); 146 147 /* 148 * Called by transport drivers to initialize the transport independent 149 * portion of the transport instance. 150 */ 151 void svc_xprt_init(struct net *net, struct svc_xprt_class *xcl, 152 struct svc_xprt *xprt, struct svc_serv *serv) 153 { 154 memset(xprt, 0, sizeof(*xprt)); 155 xprt->xpt_class = xcl; 156 xprt->xpt_ops = xcl->xcl_ops; 157 kref_init(&xprt->xpt_ref); 158 xprt->xpt_server = serv; 159 INIT_LIST_HEAD(&xprt->xpt_list); 160 INIT_LIST_HEAD(&xprt->xpt_ready); 161 INIT_LIST_HEAD(&xprt->xpt_deferred); 162 INIT_LIST_HEAD(&xprt->xpt_users); 163 mutex_init(&xprt->xpt_mutex); 164 spin_lock_init(&xprt->xpt_lock); 165 set_bit(XPT_BUSY, &xprt->xpt_flags); 166 rpc_init_wait_queue(&xprt->xpt_bc_pending, "xpt_bc_pending"); 167 xprt->xpt_net = get_net(net); 168 } 169 EXPORT_SYMBOL_GPL(svc_xprt_init); 170 171 static struct svc_xprt *__svc_xpo_create(struct svc_xprt_class *xcl, 172 struct svc_serv *serv, 173 struct net *net, 174 const int family, 175 const unsigned short port, 176 int flags) 177 { 178 struct sockaddr_in sin = { 179 .sin_family = AF_INET, 180 .sin_addr.s_addr = htonl(INADDR_ANY), 181 .sin_port = htons(port), 182 }; 183 #if IS_ENABLED(CONFIG_IPV6) 184 struct sockaddr_in6 sin6 = { 185 .sin6_family = AF_INET6, 186 .sin6_addr = IN6ADDR_ANY_INIT, 187 .sin6_port = htons(port), 188 }; 189 #endif 190 struct sockaddr *sap; 191 size_t len; 192 193 switch (family) { 194 case PF_INET: 195 sap = (struct sockaddr *)&sin; 196 len = sizeof(sin); 197 break; 198 #if IS_ENABLED(CONFIG_IPV6) 199 case PF_INET6: 200 sap = (struct sockaddr *)&sin6; 201 len = sizeof(sin6); 202 break; 203 #endif 204 default: 205 return ERR_PTR(-EAFNOSUPPORT); 206 } 207 208 return xcl->xcl_ops->xpo_create(serv, net, sap, len, flags); 209 } 210 211 /* 212 * svc_xprt_received conditionally queues the transport for processing 213 * by another thread. The caller must hold the XPT_BUSY bit and must 214 * not thereafter touch transport data. 215 * 216 * Note: XPT_DATA only gets cleared when a read-attempt finds no (or 217 * insufficient) data. 218 */ 219 static void svc_xprt_received(struct svc_xprt *xprt) 220 { 221 WARN_ON_ONCE(!test_bit(XPT_BUSY, &xprt->xpt_flags)); 222 if (!test_bit(XPT_BUSY, &xprt->xpt_flags)) 223 return; 224 /* As soon as we clear busy, the xprt could be closed and 225 * 'put', so we need a reference to call svc_xprt_enqueue with: 226 */ 227 svc_xprt_get(xprt); 228 clear_bit(XPT_BUSY, &xprt->xpt_flags); 229 svc_xprt_enqueue(xprt); 230 svc_xprt_put(xprt); 231 } 232 233 void svc_add_new_perm_xprt(struct svc_serv *serv, struct svc_xprt *new) 234 { 235 clear_bit(XPT_TEMP, &new->xpt_flags); 236 spin_lock_bh(&serv->sv_lock); 237 list_add(&new->xpt_list, &serv->sv_permsocks); 238 spin_unlock_bh(&serv->sv_lock); 239 svc_xprt_received(new); 240 } 241 242 int svc_create_xprt(struct svc_serv *serv, const char *xprt_name, 243 struct net *net, const int family, 244 const unsigned short port, int flags) 245 { 246 struct svc_xprt_class *xcl; 247 248 dprintk("svc: creating transport %s[%d]\n", xprt_name, port); 249 spin_lock(&svc_xprt_class_lock); 250 list_for_each_entry(xcl, &svc_xprt_class_list, xcl_list) { 251 struct svc_xprt *newxprt; 252 unsigned short newport; 253 254 if (strcmp(xprt_name, xcl->xcl_name)) 255 continue; 256 257 if (!try_module_get(xcl->xcl_owner)) 258 goto err; 259 260 spin_unlock(&svc_xprt_class_lock); 261 newxprt = __svc_xpo_create(xcl, serv, net, family, port, flags); 262 if (IS_ERR(newxprt)) { 263 module_put(xcl->xcl_owner); 264 return PTR_ERR(newxprt); 265 } 266 svc_add_new_perm_xprt(serv, newxprt); 267 newport = svc_xprt_local_port(newxprt); 268 return newport; 269 } 270 err: 271 spin_unlock(&svc_xprt_class_lock); 272 dprintk("svc: transport %s not found\n", xprt_name); 273 274 /* This errno is exposed to user space. Provide a reasonable 275 * perror msg for a bad transport. */ 276 return -EPROTONOSUPPORT; 277 } 278 EXPORT_SYMBOL_GPL(svc_create_xprt); 279 280 /* 281 * Copy the local and remote xprt addresses to the rqstp structure 282 */ 283 void svc_xprt_copy_addrs(struct svc_rqst *rqstp, struct svc_xprt *xprt) 284 { 285 memcpy(&rqstp->rq_addr, &xprt->xpt_remote, xprt->xpt_remotelen); 286 rqstp->rq_addrlen = xprt->xpt_remotelen; 287 288 /* 289 * Destination address in request is needed for binding the 290 * source address in RPC replies/callbacks later. 291 */ 292 memcpy(&rqstp->rq_daddr, &xprt->xpt_local, xprt->xpt_locallen); 293 rqstp->rq_daddrlen = xprt->xpt_locallen; 294 } 295 EXPORT_SYMBOL_GPL(svc_xprt_copy_addrs); 296 297 /** 298 * svc_print_addr - Format rq_addr field for printing 299 * @rqstp: svc_rqst struct containing address to print 300 * @buf: target buffer for formatted address 301 * @len: length of target buffer 302 * 303 */ 304 char *svc_print_addr(struct svc_rqst *rqstp, char *buf, size_t len) 305 { 306 return __svc_print_addr(svc_addr(rqstp), buf, len); 307 } 308 EXPORT_SYMBOL_GPL(svc_print_addr); 309 310 /* 311 * Queue up an idle server thread. Must have pool->sp_lock held. 312 * Note: this is really a stack rather than a queue, so that we only 313 * use as many different threads as we need, and the rest don't pollute 314 * the cache. 315 */ 316 static void svc_thread_enqueue(struct svc_pool *pool, struct svc_rqst *rqstp) 317 { 318 list_add(&rqstp->rq_list, &pool->sp_threads); 319 } 320 321 /* 322 * Dequeue an nfsd thread. Must have pool->sp_lock held. 323 */ 324 static void svc_thread_dequeue(struct svc_pool *pool, struct svc_rqst *rqstp) 325 { 326 list_del(&rqstp->rq_list); 327 } 328 329 static bool svc_xprt_has_something_to_do(struct svc_xprt *xprt) 330 { 331 if (xprt->xpt_flags & ((1<<XPT_CONN)|(1<<XPT_CLOSE))) 332 return true; 333 if (xprt->xpt_flags & ((1<<XPT_DATA)|(1<<XPT_DEFERRED))) 334 return xprt->xpt_ops->xpo_has_wspace(xprt); 335 return false; 336 } 337 338 /* 339 * Queue up a transport with data pending. If there are idle nfsd 340 * processes, wake 'em up. 341 * 342 */ 343 void svc_xprt_enqueue(struct svc_xprt *xprt) 344 { 345 struct svc_pool *pool; 346 struct svc_rqst *rqstp; 347 int cpu; 348 349 if (!svc_xprt_has_something_to_do(xprt)) 350 return; 351 352 cpu = get_cpu(); 353 pool = svc_pool_for_cpu(xprt->xpt_server, cpu); 354 put_cpu(); 355 356 spin_lock_bh(&pool->sp_lock); 357 358 if (!list_empty(&pool->sp_threads) && 359 !list_empty(&pool->sp_sockets)) 360 printk(KERN_ERR 361 "svc_xprt_enqueue: " 362 "threads and transports both waiting??\n"); 363 364 pool->sp_stats.packets++; 365 366 /* Mark transport as busy. It will remain in this state until 367 * the provider calls svc_xprt_received. We update XPT_BUSY 368 * atomically because it also guards against trying to enqueue 369 * the transport twice. 370 */ 371 if (test_and_set_bit(XPT_BUSY, &xprt->xpt_flags)) { 372 /* Don't enqueue transport while already enqueued */ 373 dprintk("svc: transport %p busy, not enqueued\n", xprt); 374 goto out_unlock; 375 } 376 377 if (!list_empty(&pool->sp_threads)) { 378 rqstp = list_entry(pool->sp_threads.next, 379 struct svc_rqst, 380 rq_list); 381 dprintk("svc: transport %p served by daemon %p\n", 382 xprt, rqstp); 383 svc_thread_dequeue(pool, rqstp); 384 if (rqstp->rq_xprt) 385 printk(KERN_ERR 386 "svc_xprt_enqueue: server %p, rq_xprt=%p!\n", 387 rqstp, rqstp->rq_xprt); 388 rqstp->rq_xprt = xprt; 389 svc_xprt_get(xprt); 390 pool->sp_stats.threads_woken++; 391 wake_up(&rqstp->rq_wait); 392 } else { 393 dprintk("svc: transport %p put into queue\n", xprt); 394 list_add_tail(&xprt->xpt_ready, &pool->sp_sockets); 395 pool->sp_stats.sockets_queued++; 396 } 397 398 out_unlock: 399 spin_unlock_bh(&pool->sp_lock); 400 } 401 EXPORT_SYMBOL_GPL(svc_xprt_enqueue); 402 403 /* 404 * Dequeue the first transport. Must be called with the pool->sp_lock held. 405 */ 406 static struct svc_xprt *svc_xprt_dequeue(struct svc_pool *pool) 407 { 408 struct svc_xprt *xprt; 409 410 if (list_empty(&pool->sp_sockets)) 411 return NULL; 412 413 xprt = list_entry(pool->sp_sockets.next, 414 struct svc_xprt, xpt_ready); 415 list_del_init(&xprt->xpt_ready); 416 417 dprintk("svc: transport %p dequeued, inuse=%d\n", 418 xprt, atomic_read(&xprt->xpt_ref.refcount)); 419 420 return xprt; 421 } 422 423 /** 424 * svc_reserve - change the space reserved for the reply to a request. 425 * @rqstp: The request in question 426 * @space: new max space to reserve 427 * 428 * Each request reserves some space on the output queue of the transport 429 * to make sure the reply fits. This function reduces that reserved 430 * space to be the amount of space used already, plus @space. 431 * 432 */ 433 void svc_reserve(struct svc_rqst *rqstp, int space) 434 { 435 space += rqstp->rq_res.head[0].iov_len; 436 437 if (space < rqstp->rq_reserved) { 438 struct svc_xprt *xprt = rqstp->rq_xprt; 439 atomic_sub((rqstp->rq_reserved - space), &xprt->xpt_reserved); 440 rqstp->rq_reserved = space; 441 442 svc_xprt_enqueue(xprt); 443 } 444 } 445 EXPORT_SYMBOL_GPL(svc_reserve); 446 447 static void svc_xprt_release(struct svc_rqst *rqstp) 448 { 449 struct svc_xprt *xprt = rqstp->rq_xprt; 450 451 rqstp->rq_xprt->xpt_ops->xpo_release_rqst(rqstp); 452 453 kfree(rqstp->rq_deferred); 454 rqstp->rq_deferred = NULL; 455 456 svc_free_res_pages(rqstp); 457 rqstp->rq_res.page_len = 0; 458 rqstp->rq_res.page_base = 0; 459 460 /* Reset response buffer and release 461 * the reservation. 462 * But first, check that enough space was reserved 463 * for the reply, otherwise we have a bug! 464 */ 465 if ((rqstp->rq_res.len) > rqstp->rq_reserved) 466 printk(KERN_ERR "RPC request reserved %d but used %d\n", 467 rqstp->rq_reserved, 468 rqstp->rq_res.len); 469 470 rqstp->rq_res.head[0].iov_len = 0; 471 svc_reserve(rqstp, 0); 472 rqstp->rq_xprt = NULL; 473 474 svc_xprt_put(xprt); 475 } 476 477 /* 478 * External function to wake up a server waiting for data 479 * This really only makes sense for services like lockd 480 * which have exactly one thread anyway. 481 */ 482 void svc_wake_up(struct svc_serv *serv) 483 { 484 struct svc_rqst *rqstp; 485 unsigned int i; 486 struct svc_pool *pool; 487 488 for (i = 0; i < serv->sv_nrpools; i++) { 489 pool = &serv->sv_pools[i]; 490 491 spin_lock_bh(&pool->sp_lock); 492 if (!list_empty(&pool->sp_threads)) { 493 rqstp = list_entry(pool->sp_threads.next, 494 struct svc_rqst, 495 rq_list); 496 dprintk("svc: daemon %p woken up.\n", rqstp); 497 /* 498 svc_thread_dequeue(pool, rqstp); 499 rqstp->rq_xprt = NULL; 500 */ 501 wake_up(&rqstp->rq_wait); 502 } else 503 pool->sp_task_pending = 1; 504 spin_unlock_bh(&pool->sp_lock); 505 } 506 } 507 EXPORT_SYMBOL_GPL(svc_wake_up); 508 509 int svc_port_is_privileged(struct sockaddr *sin) 510 { 511 switch (sin->sa_family) { 512 case AF_INET: 513 return ntohs(((struct sockaddr_in *)sin)->sin_port) 514 < PROT_SOCK; 515 case AF_INET6: 516 return ntohs(((struct sockaddr_in6 *)sin)->sin6_port) 517 < PROT_SOCK; 518 default: 519 return 0; 520 } 521 } 522 523 /* 524 * Make sure that we don't have too many active connections. If we have, 525 * something must be dropped. It's not clear what will happen if we allow 526 * "too many" connections, but when dealing with network-facing software, 527 * we have to code defensively. Here we do that by imposing hard limits. 528 * 529 * There's no point in trying to do random drop here for DoS 530 * prevention. The NFS clients does 1 reconnect in 15 seconds. An 531 * attacker can easily beat that. 532 * 533 * The only somewhat efficient mechanism would be if drop old 534 * connections from the same IP first. But right now we don't even 535 * record the client IP in svc_sock. 536 * 537 * single-threaded services that expect a lot of clients will probably 538 * need to set sv_maxconn to override the default value which is based 539 * on the number of threads 540 */ 541 static void svc_check_conn_limits(struct svc_serv *serv) 542 { 543 unsigned int limit = serv->sv_maxconn ? serv->sv_maxconn : 544 (serv->sv_nrthreads+3) * 20; 545 546 if (serv->sv_tmpcnt > limit) { 547 struct svc_xprt *xprt = NULL; 548 spin_lock_bh(&serv->sv_lock); 549 if (!list_empty(&serv->sv_tempsocks)) { 550 /* Try to help the admin */ 551 net_notice_ratelimited("%s: too many open connections, consider increasing the %s\n", 552 serv->sv_name, serv->sv_maxconn ? 553 "max number of connections" : 554 "number of threads"); 555 /* 556 * Always select the oldest connection. It's not fair, 557 * but so is life 558 */ 559 xprt = list_entry(serv->sv_tempsocks.prev, 560 struct svc_xprt, 561 xpt_list); 562 set_bit(XPT_CLOSE, &xprt->xpt_flags); 563 svc_xprt_get(xprt); 564 } 565 spin_unlock_bh(&serv->sv_lock); 566 567 if (xprt) { 568 svc_xprt_enqueue(xprt); 569 svc_xprt_put(xprt); 570 } 571 } 572 } 573 574 int svc_alloc_arg(struct svc_rqst *rqstp) 575 { 576 struct svc_serv *serv = rqstp->rq_server; 577 struct xdr_buf *arg; 578 int pages; 579 int i; 580 581 /* now allocate needed pages. If we get a failure, sleep briefly */ 582 pages = (serv->sv_max_mesg + PAGE_SIZE) / PAGE_SIZE; 583 WARN_ON_ONCE(pages >= RPCSVC_MAXPAGES); 584 if (pages >= RPCSVC_MAXPAGES) 585 /* use as many pages as possible */ 586 pages = RPCSVC_MAXPAGES - 1; 587 for (i = 0; i < pages ; i++) 588 while (rqstp->rq_pages[i] == NULL) { 589 struct page *p = alloc_page(GFP_KERNEL); 590 if (!p) { 591 set_current_state(TASK_INTERRUPTIBLE); 592 if (signalled() || kthread_should_stop()) { 593 set_current_state(TASK_RUNNING); 594 return -EINTR; 595 } 596 schedule_timeout(msecs_to_jiffies(500)); 597 } 598 rqstp->rq_pages[i] = p; 599 } 600 rqstp->rq_pages[i++] = NULL; /* this might be seen in nfs_read_actor */ 601 602 /* Make arg->head point to first page and arg->pages point to rest */ 603 arg = &rqstp->rq_arg; 604 arg->head[0].iov_base = page_address(rqstp->rq_pages[0]); 605 arg->head[0].iov_len = PAGE_SIZE; 606 arg->pages = rqstp->rq_pages + 1; 607 arg->page_base = 0; 608 /* save at least one page for response */ 609 arg->page_len = (pages-2)*PAGE_SIZE; 610 arg->len = (pages-1)*PAGE_SIZE; 611 arg->tail[0].iov_len = 0; 612 return 0; 613 } 614 615 struct svc_xprt *svc_get_next_xprt(struct svc_rqst *rqstp, long timeout) 616 { 617 struct svc_xprt *xprt; 618 struct svc_pool *pool = rqstp->rq_pool; 619 DECLARE_WAITQUEUE(wait, current); 620 long time_left; 621 622 /* Normally we will wait up to 5 seconds for any required 623 * cache information to be provided. 624 */ 625 rqstp->rq_chandle.thread_wait = 5*HZ; 626 627 spin_lock_bh(&pool->sp_lock); 628 xprt = svc_xprt_dequeue(pool); 629 if (xprt) { 630 rqstp->rq_xprt = xprt; 631 svc_xprt_get(xprt); 632 633 /* As there is a shortage of threads and this request 634 * had to be queued, don't allow the thread to wait so 635 * long for cache updates. 636 */ 637 rqstp->rq_chandle.thread_wait = 1*HZ; 638 pool->sp_task_pending = 0; 639 } else { 640 if (pool->sp_task_pending) { 641 pool->sp_task_pending = 0; 642 spin_unlock_bh(&pool->sp_lock); 643 return ERR_PTR(-EAGAIN); 644 } 645 /* No data pending. Go to sleep */ 646 svc_thread_enqueue(pool, rqstp); 647 648 /* 649 * We have to be able to interrupt this wait 650 * to bring down the daemons ... 651 */ 652 set_current_state(TASK_INTERRUPTIBLE); 653 654 /* 655 * checking kthread_should_stop() here allows us to avoid 656 * locking and signalling when stopping kthreads that call 657 * svc_recv. If the thread has already been woken up, then 658 * we can exit here without sleeping. If not, then it 659 * it'll be woken up quickly during the schedule_timeout 660 */ 661 if (kthread_should_stop()) { 662 set_current_state(TASK_RUNNING); 663 spin_unlock_bh(&pool->sp_lock); 664 return ERR_PTR(-EINTR); 665 } 666 667 add_wait_queue(&rqstp->rq_wait, &wait); 668 spin_unlock_bh(&pool->sp_lock); 669 670 time_left = schedule_timeout(timeout); 671 672 try_to_freeze(); 673 674 spin_lock_bh(&pool->sp_lock); 675 remove_wait_queue(&rqstp->rq_wait, &wait); 676 if (!time_left) 677 pool->sp_stats.threads_timedout++; 678 679 xprt = rqstp->rq_xprt; 680 if (!xprt) { 681 svc_thread_dequeue(pool, rqstp); 682 spin_unlock_bh(&pool->sp_lock); 683 dprintk("svc: server %p, no data yet\n", rqstp); 684 if (signalled() || kthread_should_stop()) 685 return ERR_PTR(-EINTR); 686 else 687 return ERR_PTR(-EAGAIN); 688 } 689 } 690 spin_unlock_bh(&pool->sp_lock); 691 return xprt; 692 } 693 694 void svc_add_new_temp_xprt(struct svc_serv *serv, struct svc_xprt *newxpt) 695 { 696 spin_lock_bh(&serv->sv_lock); 697 set_bit(XPT_TEMP, &newxpt->xpt_flags); 698 list_add(&newxpt->xpt_list, &serv->sv_tempsocks); 699 serv->sv_tmpcnt++; 700 if (serv->sv_temptimer.function == NULL) { 701 /* setup timer to age temp transports */ 702 setup_timer(&serv->sv_temptimer, svc_age_temp_xprts, 703 (unsigned long)serv); 704 mod_timer(&serv->sv_temptimer, 705 jiffies + svc_conn_age_period * HZ); 706 } 707 spin_unlock_bh(&serv->sv_lock); 708 svc_xprt_received(newxpt); 709 } 710 711 static int svc_handle_xprt(struct svc_rqst *rqstp, struct svc_xprt *xprt) 712 { 713 struct svc_serv *serv = rqstp->rq_server; 714 int len = 0; 715 716 if (test_bit(XPT_CLOSE, &xprt->xpt_flags)) { 717 dprintk("svc_recv: found XPT_CLOSE\n"); 718 svc_delete_xprt(xprt); 719 /* Leave XPT_BUSY set on the dead xprt: */ 720 return 0; 721 } 722 if (test_bit(XPT_LISTENER, &xprt->xpt_flags)) { 723 struct svc_xprt *newxpt; 724 /* 725 * We know this module_get will succeed because the 726 * listener holds a reference too 727 */ 728 __module_get(xprt->xpt_class->xcl_owner); 729 svc_check_conn_limits(xprt->xpt_server); 730 newxpt = xprt->xpt_ops->xpo_accept(xprt); 731 if (newxpt) 732 svc_add_new_temp_xprt(serv, newxpt); 733 } else if (xprt->xpt_ops->xpo_has_wspace(xprt)) { 734 /* XPT_DATA|XPT_DEFERRED case: */ 735 dprintk("svc: server %p, pool %u, transport %p, inuse=%d\n", 736 rqstp, rqstp->rq_pool->sp_id, xprt, 737 atomic_read(&xprt->xpt_ref.refcount)); 738 rqstp->rq_deferred = svc_deferred_dequeue(xprt); 739 if (rqstp->rq_deferred) 740 len = svc_deferred_recv(rqstp); 741 else 742 len = xprt->xpt_ops->xpo_recvfrom(rqstp); 743 dprintk("svc: got len=%d\n", len); 744 rqstp->rq_reserved = serv->sv_max_mesg; 745 atomic_add(rqstp->rq_reserved, &xprt->xpt_reserved); 746 } 747 /* clear XPT_BUSY: */ 748 svc_xprt_received(xprt); 749 return len; 750 } 751 752 /* 753 * Receive the next request on any transport. This code is carefully 754 * organised not to touch any cachelines in the shared svc_serv 755 * structure, only cachelines in the local svc_pool. 756 */ 757 int svc_recv(struct svc_rqst *rqstp, long timeout) 758 { 759 struct svc_xprt *xprt = NULL; 760 struct svc_serv *serv = rqstp->rq_server; 761 int len, err; 762 763 dprintk("svc: server %p waiting for data (to = %ld)\n", 764 rqstp, timeout); 765 766 if (rqstp->rq_xprt) 767 printk(KERN_ERR 768 "svc_recv: service %p, transport not NULL!\n", 769 rqstp); 770 if (waitqueue_active(&rqstp->rq_wait)) 771 printk(KERN_ERR 772 "svc_recv: service %p, wait queue active!\n", 773 rqstp); 774 775 err = svc_alloc_arg(rqstp); 776 if (err) 777 return err; 778 779 try_to_freeze(); 780 cond_resched(); 781 if (signalled() || kthread_should_stop()) 782 return -EINTR; 783 784 xprt = svc_get_next_xprt(rqstp, timeout); 785 if (IS_ERR(xprt)) 786 return PTR_ERR(xprt); 787 788 len = svc_handle_xprt(rqstp, xprt); 789 790 /* No data, incomplete (TCP) read, or accept() */ 791 if (len <= 0) 792 goto out; 793 794 clear_bit(XPT_OLD, &xprt->xpt_flags); 795 796 rqstp->rq_secure = svc_port_is_privileged(svc_addr(rqstp)); 797 rqstp->rq_chandle.defer = svc_defer; 798 799 if (serv->sv_stats) 800 serv->sv_stats->netcnt++; 801 return len; 802 out: 803 rqstp->rq_res.len = 0; 804 svc_xprt_release(rqstp); 805 return -EAGAIN; 806 } 807 EXPORT_SYMBOL_GPL(svc_recv); 808 809 /* 810 * Drop request 811 */ 812 void svc_drop(struct svc_rqst *rqstp) 813 { 814 dprintk("svc: xprt %p dropped request\n", rqstp->rq_xprt); 815 svc_xprt_release(rqstp); 816 } 817 EXPORT_SYMBOL_GPL(svc_drop); 818 819 /* 820 * Return reply to client. 821 */ 822 int svc_send(struct svc_rqst *rqstp) 823 { 824 struct svc_xprt *xprt; 825 int len; 826 struct xdr_buf *xb; 827 828 xprt = rqstp->rq_xprt; 829 if (!xprt) 830 return -EFAULT; 831 832 /* release the receive skb before sending the reply */ 833 rqstp->rq_xprt->xpt_ops->xpo_release_rqst(rqstp); 834 835 /* calculate over-all length */ 836 xb = &rqstp->rq_res; 837 xb->len = xb->head[0].iov_len + 838 xb->page_len + 839 xb->tail[0].iov_len; 840 841 /* Grab mutex to serialize outgoing data. */ 842 mutex_lock(&xprt->xpt_mutex); 843 if (test_bit(XPT_DEAD, &xprt->xpt_flags) 844 || test_bit(XPT_CLOSE, &xprt->xpt_flags)) 845 len = -ENOTCONN; 846 else 847 len = xprt->xpt_ops->xpo_sendto(rqstp); 848 mutex_unlock(&xprt->xpt_mutex); 849 rpc_wake_up(&xprt->xpt_bc_pending); 850 svc_xprt_release(rqstp); 851 852 if (len == -ECONNREFUSED || len == -ENOTCONN || len == -EAGAIN) 853 return 0; 854 return len; 855 } 856 857 /* 858 * Timer function to close old temporary transports, using 859 * a mark-and-sweep algorithm. 860 */ 861 static void svc_age_temp_xprts(unsigned long closure) 862 { 863 struct svc_serv *serv = (struct svc_serv *)closure; 864 struct svc_xprt *xprt; 865 struct list_head *le, *next; 866 867 dprintk("svc_age_temp_xprts\n"); 868 869 if (!spin_trylock_bh(&serv->sv_lock)) { 870 /* busy, try again 1 sec later */ 871 dprintk("svc_age_temp_xprts: busy\n"); 872 mod_timer(&serv->sv_temptimer, jiffies + HZ); 873 return; 874 } 875 876 list_for_each_safe(le, next, &serv->sv_tempsocks) { 877 xprt = list_entry(le, struct svc_xprt, xpt_list); 878 879 /* First time through, just mark it OLD. Second time 880 * through, close it. */ 881 if (!test_and_set_bit(XPT_OLD, &xprt->xpt_flags)) 882 continue; 883 if (atomic_read(&xprt->xpt_ref.refcount) > 1 || 884 test_bit(XPT_BUSY, &xprt->xpt_flags)) 885 continue; 886 list_del_init(le); 887 set_bit(XPT_CLOSE, &xprt->xpt_flags); 888 set_bit(XPT_DETACHED, &xprt->xpt_flags); 889 dprintk("queuing xprt %p for closing\n", xprt); 890 891 /* a thread will dequeue and close it soon */ 892 svc_xprt_enqueue(xprt); 893 } 894 spin_unlock_bh(&serv->sv_lock); 895 896 mod_timer(&serv->sv_temptimer, jiffies + svc_conn_age_period * HZ); 897 } 898 899 static void call_xpt_users(struct svc_xprt *xprt) 900 { 901 struct svc_xpt_user *u; 902 903 spin_lock(&xprt->xpt_lock); 904 while (!list_empty(&xprt->xpt_users)) { 905 u = list_first_entry(&xprt->xpt_users, struct svc_xpt_user, list); 906 list_del(&u->list); 907 u->callback(u); 908 } 909 spin_unlock(&xprt->xpt_lock); 910 } 911 912 /* 913 * Remove a dead transport 914 */ 915 static void svc_delete_xprt(struct svc_xprt *xprt) 916 { 917 struct svc_serv *serv = xprt->xpt_server; 918 struct svc_deferred_req *dr; 919 920 /* Only do this once */ 921 if (test_and_set_bit(XPT_DEAD, &xprt->xpt_flags)) 922 BUG(); 923 924 dprintk("svc: svc_delete_xprt(%p)\n", xprt); 925 xprt->xpt_ops->xpo_detach(xprt); 926 927 spin_lock_bh(&serv->sv_lock); 928 if (!test_and_set_bit(XPT_DETACHED, &xprt->xpt_flags)) 929 list_del_init(&xprt->xpt_list); 930 WARN_ON_ONCE(!list_empty(&xprt->xpt_ready)); 931 if (test_bit(XPT_TEMP, &xprt->xpt_flags)) 932 serv->sv_tmpcnt--; 933 spin_unlock_bh(&serv->sv_lock); 934 935 while ((dr = svc_deferred_dequeue(xprt)) != NULL) 936 kfree(dr); 937 938 call_xpt_users(xprt); 939 svc_xprt_put(xprt); 940 } 941 942 void svc_close_xprt(struct svc_xprt *xprt) 943 { 944 set_bit(XPT_CLOSE, &xprt->xpt_flags); 945 if (test_and_set_bit(XPT_BUSY, &xprt->xpt_flags)) 946 /* someone else will have to effect the close */ 947 return; 948 /* 949 * We expect svc_close_xprt() to work even when no threads are 950 * running (e.g., while configuring the server before starting 951 * any threads), so if the transport isn't busy, we delete 952 * it ourself: 953 */ 954 svc_delete_xprt(xprt); 955 } 956 EXPORT_SYMBOL_GPL(svc_close_xprt); 957 958 static int svc_close_list(struct svc_serv *serv, struct list_head *xprt_list, struct net *net) 959 { 960 struct svc_xprt *xprt; 961 int ret = 0; 962 963 spin_lock(&serv->sv_lock); 964 list_for_each_entry(xprt, xprt_list, xpt_list) { 965 if (xprt->xpt_net != net) 966 continue; 967 ret++; 968 set_bit(XPT_CLOSE, &xprt->xpt_flags); 969 svc_xprt_enqueue(xprt); 970 } 971 spin_unlock(&serv->sv_lock); 972 return ret; 973 } 974 975 static struct svc_xprt *svc_dequeue_net(struct svc_serv *serv, struct net *net) 976 { 977 struct svc_pool *pool; 978 struct svc_xprt *xprt; 979 struct svc_xprt *tmp; 980 int i; 981 982 for (i = 0; i < serv->sv_nrpools; i++) { 983 pool = &serv->sv_pools[i]; 984 985 spin_lock_bh(&pool->sp_lock); 986 list_for_each_entry_safe(xprt, tmp, &pool->sp_sockets, xpt_ready) { 987 if (xprt->xpt_net != net) 988 continue; 989 list_del_init(&xprt->xpt_ready); 990 spin_unlock_bh(&pool->sp_lock); 991 return xprt; 992 } 993 spin_unlock_bh(&pool->sp_lock); 994 } 995 return NULL; 996 } 997 998 static void svc_clean_up_xprts(struct svc_serv *serv, struct net *net) 999 { 1000 struct svc_xprt *xprt; 1001 1002 while ((xprt = svc_dequeue_net(serv, net))) { 1003 set_bit(XPT_CLOSE, &xprt->xpt_flags); 1004 svc_delete_xprt(xprt); 1005 } 1006 } 1007 1008 /* 1009 * Server threads may still be running (especially in the case where the 1010 * service is still running in other network namespaces). 1011 * 1012 * So we shut down sockets the same way we would on a running server, by 1013 * setting XPT_CLOSE, enqueuing, and letting a thread pick it up to do 1014 * the close. In the case there are no such other threads, 1015 * threads running, svc_clean_up_xprts() does a simple version of a 1016 * server's main event loop, and in the case where there are other 1017 * threads, we may need to wait a little while and then check again to 1018 * see if they're done. 1019 */ 1020 void svc_close_net(struct svc_serv *serv, struct net *net) 1021 { 1022 int delay = 0; 1023 1024 while (svc_close_list(serv, &serv->sv_permsocks, net) + 1025 svc_close_list(serv, &serv->sv_tempsocks, net)) { 1026 1027 svc_clean_up_xprts(serv, net); 1028 msleep(delay++); 1029 } 1030 } 1031 1032 /* 1033 * Handle defer and revisit of requests 1034 */ 1035 1036 static void svc_revisit(struct cache_deferred_req *dreq, int too_many) 1037 { 1038 struct svc_deferred_req *dr = 1039 container_of(dreq, struct svc_deferred_req, handle); 1040 struct svc_xprt *xprt = dr->xprt; 1041 1042 spin_lock(&xprt->xpt_lock); 1043 set_bit(XPT_DEFERRED, &xprt->xpt_flags); 1044 if (too_many || test_bit(XPT_DEAD, &xprt->xpt_flags)) { 1045 spin_unlock(&xprt->xpt_lock); 1046 dprintk("revisit canceled\n"); 1047 svc_xprt_put(xprt); 1048 kfree(dr); 1049 return; 1050 } 1051 dprintk("revisit queued\n"); 1052 dr->xprt = NULL; 1053 list_add(&dr->handle.recent, &xprt->xpt_deferred); 1054 spin_unlock(&xprt->xpt_lock); 1055 svc_xprt_enqueue(xprt); 1056 svc_xprt_put(xprt); 1057 } 1058 1059 /* 1060 * Save the request off for later processing. The request buffer looks 1061 * like this: 1062 * 1063 * <xprt-header><rpc-header><rpc-pagelist><rpc-tail> 1064 * 1065 * This code can only handle requests that consist of an xprt-header 1066 * and rpc-header. 1067 */ 1068 static struct cache_deferred_req *svc_defer(struct cache_req *req) 1069 { 1070 struct svc_rqst *rqstp = container_of(req, struct svc_rqst, rq_chandle); 1071 struct svc_deferred_req *dr; 1072 1073 if (rqstp->rq_arg.page_len || !rqstp->rq_usedeferral) 1074 return NULL; /* if more than a page, give up FIXME */ 1075 if (rqstp->rq_deferred) { 1076 dr = rqstp->rq_deferred; 1077 rqstp->rq_deferred = NULL; 1078 } else { 1079 size_t skip; 1080 size_t size; 1081 /* FIXME maybe discard if size too large */ 1082 size = sizeof(struct svc_deferred_req) + rqstp->rq_arg.len; 1083 dr = kmalloc(size, GFP_KERNEL); 1084 if (dr == NULL) 1085 return NULL; 1086 1087 dr->handle.owner = rqstp->rq_server; 1088 dr->prot = rqstp->rq_prot; 1089 memcpy(&dr->addr, &rqstp->rq_addr, rqstp->rq_addrlen); 1090 dr->addrlen = rqstp->rq_addrlen; 1091 dr->daddr = rqstp->rq_daddr; 1092 dr->argslen = rqstp->rq_arg.len >> 2; 1093 dr->xprt_hlen = rqstp->rq_xprt_hlen; 1094 1095 /* back up head to the start of the buffer and copy */ 1096 skip = rqstp->rq_arg.len - rqstp->rq_arg.head[0].iov_len; 1097 memcpy(dr->args, rqstp->rq_arg.head[0].iov_base - skip, 1098 dr->argslen << 2); 1099 } 1100 svc_xprt_get(rqstp->rq_xprt); 1101 dr->xprt = rqstp->rq_xprt; 1102 rqstp->rq_dropme = true; 1103 1104 dr->handle.revisit = svc_revisit; 1105 return &dr->handle; 1106 } 1107 1108 /* 1109 * recv data from a deferred request into an active one 1110 */ 1111 static int svc_deferred_recv(struct svc_rqst *rqstp) 1112 { 1113 struct svc_deferred_req *dr = rqstp->rq_deferred; 1114 1115 /* setup iov_base past transport header */ 1116 rqstp->rq_arg.head[0].iov_base = dr->args + (dr->xprt_hlen>>2); 1117 /* The iov_len does not include the transport header bytes */ 1118 rqstp->rq_arg.head[0].iov_len = (dr->argslen<<2) - dr->xprt_hlen; 1119 rqstp->rq_arg.page_len = 0; 1120 /* The rq_arg.len includes the transport header bytes */ 1121 rqstp->rq_arg.len = dr->argslen<<2; 1122 rqstp->rq_prot = dr->prot; 1123 memcpy(&rqstp->rq_addr, &dr->addr, dr->addrlen); 1124 rqstp->rq_addrlen = dr->addrlen; 1125 /* Save off transport header len in case we get deferred again */ 1126 rqstp->rq_xprt_hlen = dr->xprt_hlen; 1127 rqstp->rq_daddr = dr->daddr; 1128 rqstp->rq_respages = rqstp->rq_pages; 1129 return (dr->argslen<<2) - dr->xprt_hlen; 1130 } 1131 1132 1133 static struct svc_deferred_req *svc_deferred_dequeue(struct svc_xprt *xprt) 1134 { 1135 struct svc_deferred_req *dr = NULL; 1136 1137 if (!test_bit(XPT_DEFERRED, &xprt->xpt_flags)) 1138 return NULL; 1139 spin_lock(&xprt->xpt_lock); 1140 if (!list_empty(&xprt->xpt_deferred)) { 1141 dr = list_entry(xprt->xpt_deferred.next, 1142 struct svc_deferred_req, 1143 handle.recent); 1144 list_del_init(&dr->handle.recent); 1145 } else 1146 clear_bit(XPT_DEFERRED, &xprt->xpt_flags); 1147 spin_unlock(&xprt->xpt_lock); 1148 return dr; 1149 } 1150 1151 /** 1152 * svc_find_xprt - find an RPC transport instance 1153 * @serv: pointer to svc_serv to search 1154 * @xcl_name: C string containing transport's class name 1155 * @net: owner net pointer 1156 * @af: Address family of transport's local address 1157 * @port: transport's IP port number 1158 * 1159 * Return the transport instance pointer for the endpoint accepting 1160 * connections/peer traffic from the specified transport class, 1161 * address family and port. 1162 * 1163 * Specifying 0 for the address family or port is effectively a 1164 * wild-card, and will result in matching the first transport in the 1165 * service's list that has a matching class name. 1166 */ 1167 struct svc_xprt *svc_find_xprt(struct svc_serv *serv, const char *xcl_name, 1168 struct net *net, const sa_family_t af, 1169 const unsigned short port) 1170 { 1171 struct svc_xprt *xprt; 1172 struct svc_xprt *found = NULL; 1173 1174 /* Sanity check the args */ 1175 if (serv == NULL || xcl_name == NULL) 1176 return found; 1177 1178 spin_lock_bh(&serv->sv_lock); 1179 list_for_each_entry(xprt, &serv->sv_permsocks, xpt_list) { 1180 if (xprt->xpt_net != net) 1181 continue; 1182 if (strcmp(xprt->xpt_class->xcl_name, xcl_name)) 1183 continue; 1184 if (af != AF_UNSPEC && af != xprt->xpt_local.ss_family) 1185 continue; 1186 if (port != 0 && port != svc_xprt_local_port(xprt)) 1187 continue; 1188 found = xprt; 1189 svc_xprt_get(xprt); 1190 break; 1191 } 1192 spin_unlock_bh(&serv->sv_lock); 1193 return found; 1194 } 1195 EXPORT_SYMBOL_GPL(svc_find_xprt); 1196 1197 static int svc_one_xprt_name(const struct svc_xprt *xprt, 1198 char *pos, int remaining) 1199 { 1200 int len; 1201 1202 len = snprintf(pos, remaining, "%s %u\n", 1203 xprt->xpt_class->xcl_name, 1204 svc_xprt_local_port(xprt)); 1205 if (len >= remaining) 1206 return -ENAMETOOLONG; 1207 return len; 1208 } 1209 1210 /** 1211 * svc_xprt_names - format a buffer with a list of transport names 1212 * @serv: pointer to an RPC service 1213 * @buf: pointer to a buffer to be filled in 1214 * @buflen: length of buffer to be filled in 1215 * 1216 * Fills in @buf with a string containing a list of transport names, 1217 * each name terminated with '\n'. 1218 * 1219 * Returns positive length of the filled-in string on success; otherwise 1220 * a negative errno value is returned if an error occurs. 1221 */ 1222 int svc_xprt_names(struct svc_serv *serv, char *buf, const int buflen) 1223 { 1224 struct svc_xprt *xprt; 1225 int len, totlen; 1226 char *pos; 1227 1228 /* Sanity check args */ 1229 if (!serv) 1230 return 0; 1231 1232 spin_lock_bh(&serv->sv_lock); 1233 1234 pos = buf; 1235 totlen = 0; 1236 list_for_each_entry(xprt, &serv->sv_permsocks, xpt_list) { 1237 len = svc_one_xprt_name(xprt, pos, buflen - totlen); 1238 if (len < 0) { 1239 *buf = '\0'; 1240 totlen = len; 1241 } 1242 if (len <= 0) 1243 break; 1244 1245 pos += len; 1246 totlen += len; 1247 } 1248 1249 spin_unlock_bh(&serv->sv_lock); 1250 return totlen; 1251 } 1252 EXPORT_SYMBOL_GPL(svc_xprt_names); 1253 1254 1255 /*----------------------------------------------------------------------------*/ 1256 1257 static void *svc_pool_stats_start(struct seq_file *m, loff_t *pos) 1258 { 1259 unsigned int pidx = (unsigned int)*pos; 1260 struct svc_serv *serv = m->private; 1261 1262 dprintk("svc_pool_stats_start, *pidx=%u\n", pidx); 1263 1264 if (!pidx) 1265 return SEQ_START_TOKEN; 1266 return (pidx > serv->sv_nrpools ? NULL : &serv->sv_pools[pidx-1]); 1267 } 1268 1269 static void *svc_pool_stats_next(struct seq_file *m, void *p, loff_t *pos) 1270 { 1271 struct svc_pool *pool = p; 1272 struct svc_serv *serv = m->private; 1273 1274 dprintk("svc_pool_stats_next, *pos=%llu\n", *pos); 1275 1276 if (p == SEQ_START_TOKEN) { 1277 pool = &serv->sv_pools[0]; 1278 } else { 1279 unsigned int pidx = (pool - &serv->sv_pools[0]); 1280 if (pidx < serv->sv_nrpools-1) 1281 pool = &serv->sv_pools[pidx+1]; 1282 else 1283 pool = NULL; 1284 } 1285 ++*pos; 1286 return pool; 1287 } 1288 1289 static void svc_pool_stats_stop(struct seq_file *m, void *p) 1290 { 1291 } 1292 1293 static int svc_pool_stats_show(struct seq_file *m, void *p) 1294 { 1295 struct svc_pool *pool = p; 1296 1297 if (p == SEQ_START_TOKEN) { 1298 seq_puts(m, "# pool packets-arrived sockets-enqueued threads-woken threads-timedout\n"); 1299 return 0; 1300 } 1301 1302 seq_printf(m, "%u %lu %lu %lu %lu\n", 1303 pool->sp_id, 1304 pool->sp_stats.packets, 1305 pool->sp_stats.sockets_queued, 1306 pool->sp_stats.threads_woken, 1307 pool->sp_stats.threads_timedout); 1308 1309 return 0; 1310 } 1311 1312 static const struct seq_operations svc_pool_stats_seq_ops = { 1313 .start = svc_pool_stats_start, 1314 .next = svc_pool_stats_next, 1315 .stop = svc_pool_stats_stop, 1316 .show = svc_pool_stats_show, 1317 }; 1318 1319 int svc_pool_stats_open(struct svc_serv *serv, struct file *file) 1320 { 1321 int err; 1322 1323 err = seq_open(file, &svc_pool_stats_seq_ops); 1324 if (!err) 1325 ((struct seq_file *) file->private_data)->private = serv; 1326 return err; 1327 } 1328 EXPORT_SYMBOL(svc_pool_stats_open); 1329 1330 /*----------------------------------------------------------------------------*/ 1331