1// SPDX-License-Identifier: GPL-2.0-or-later 2/* 3 * IPVS: Locality-Based Least-Connection with Replication scheduler 4 * 5 * Authors: Wensong Zhang <wensong@gnuchina.org> 6 * 7 * Changes: 8 * Julian Anastasov : Added the missing (dest->weight>0) 9 * condition in the ip_vs_dest_set_max. 10 */ 11 12/* 13 * The lblc/r algorithm is as follows (pseudo code): 14 * 15 * if serverSet[dest_ip] is null then 16 * n, serverSet[dest_ip] <- {weighted least-conn node}; 17 * else 18 * n <- {least-conn (alive) node in serverSet[dest_ip]}; 19 * if (n is null) OR 20 * (n.conns>n.weight AND 21 * there is a node m with m.conns<m.weight/2) then 22 * n <- {weighted least-conn node}; 23 * add n to serverSet[dest_ip]; 24 * if |serverSet[dest_ip]| > 1 AND 25 * now - serverSet[dest_ip].lastMod > T then 26 * m <- {most conn node in serverSet[dest_ip]}; 27 * remove m from serverSet[dest_ip]; 28 * if serverSet[dest_ip] changed then 29 * serverSet[dest_ip].lastMod <- now; 30 * 31 * return n; 32 * 33 */ 34 35#define KMSG_COMPONENT "IPVS" 36#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt 37 38#include <linux/ip.h> 39#include <linux/module.h> 40#include <linux/kernel.h> 41#include <linux/skbuff.h> 42#include <linux/jiffies.h> 43#include <linux/list.h> 44#include <linux/slab.h> 45#include <linux/hash.h> 46 47/* for sysctl */ 48#include <linux/fs.h> 49#include <linux/sysctl.h> 50#include <net/net_namespace.h> 51 52#include <net/ip_vs.h> 53 54 55/* 56 * It is for garbage collection of stale IPVS lblcr entries, 57 * when the table is full. 58 */ 59#define CHECK_EXPIRE_INTERVAL (60*HZ) 60#define ENTRY_TIMEOUT (6*60*HZ) 61 62#define DEFAULT_EXPIRATION (24*60*60*HZ) 63 64/* 65 * It is for full expiration check. 66 * When there is no partial expiration check (garbage collection) 67 * in a half hour, do a full expiration check to collect stale 68 * entries that haven't been touched for a day. 69 */ 70#define COUNT_FOR_FULL_EXPIRATION 30 71 72/* 73 * for IPVS lblcr entry hash table 74 */ 75#ifndef CONFIG_IP_VS_LBLCR_TAB_BITS 76#define CONFIG_IP_VS_LBLCR_TAB_BITS 10 77#endif 78#define IP_VS_LBLCR_TAB_BITS CONFIG_IP_VS_LBLCR_TAB_BITS 79#define IP_VS_LBLCR_TAB_SIZE (1 << IP_VS_LBLCR_TAB_BITS) 80#define IP_VS_LBLCR_TAB_MASK (IP_VS_LBLCR_TAB_SIZE - 1) 81 82 83/* 84 * IPVS destination set structure and operations 85 */ 86struct ip_vs_dest_set_elem { 87 struct list_head list; /* list link */ 88 struct ip_vs_dest *dest; /* destination server */ 89 struct rcu_head rcu_head; 90}; 91 92struct ip_vs_dest_set { 93 atomic_t size; /* set size */ 94 unsigned long lastmod; /* last modified time */ 95 struct list_head list; /* destination list */ 96}; 97 98 99static void ip_vs_dest_set_insert(struct ip_vs_dest_set *set, 100 struct ip_vs_dest *dest, bool check) 101{ 102 struct ip_vs_dest_set_elem *e; 103 104 if (check) { 105 list_for_each_entry(e, &set->list, list) { 106 if (e->dest == dest) 107 return; 108 } 109 } 110 111 e = kmalloc(sizeof(*e), GFP_ATOMIC); 112 if (e == NULL) 113 return; 114 115 ip_vs_dest_hold(dest); 116 e->dest = dest; 117 118 list_add_rcu(&e->list, &set->list); 119 atomic_inc(&set->size); 120 121 set->lastmod = jiffies; 122} 123 124static void ip_vs_lblcr_elem_rcu_free(struct rcu_head *head) 125{ 126 struct ip_vs_dest_set_elem *e; 127 128 e = container_of(head, struct ip_vs_dest_set_elem, rcu_head); 129 ip_vs_dest_put_and_free(e->dest); 130 kfree(e); 131} 132 133static void 134ip_vs_dest_set_erase(struct ip_vs_dest_set *set, struct ip_vs_dest *dest) 135{ 136 struct ip_vs_dest_set_elem *e; 137 138 list_for_each_entry(e, &set->list, list) { 139 if (e->dest == dest) { 140 /* HIT */ 141 atomic_dec(&set->size); 142 set->lastmod = jiffies; 143 list_del_rcu(&e->list); 144 call_rcu(&e->rcu_head, ip_vs_lblcr_elem_rcu_free); 145 break; 146 } 147 } 148} 149 150static void ip_vs_dest_set_eraseall(struct ip_vs_dest_set *set) 151{ 152 struct ip_vs_dest_set_elem *e, *ep; 153 154 list_for_each_entry_safe(e, ep, &set->list, list) { 155 list_del_rcu(&e->list); 156 call_rcu(&e->rcu_head, ip_vs_lblcr_elem_rcu_free); 157 } 158} 159 160/* get weighted least-connection node in the destination set */ 161static inline struct ip_vs_dest *ip_vs_dest_set_min(struct ip_vs_dest_set *set) 162{ 163 struct ip_vs_dest_set_elem *e; 164 struct ip_vs_dest *dest, *least; 165 int loh, doh; 166 167 /* select the first destination server, whose weight > 0 */ 168 list_for_each_entry_rcu(e, &set->list, list) { 169 least = e->dest; 170 if (least->flags & IP_VS_DEST_F_OVERLOAD) 171 continue; 172 173 if ((atomic_read(&least->weight) > 0) 174 && (least->flags & IP_VS_DEST_F_AVAILABLE)) { 175 loh = ip_vs_dest_conn_overhead(least); 176 goto nextstage; 177 } 178 } 179 return NULL; 180 181 /* find the destination with the weighted least load */ 182 nextstage: 183 list_for_each_entry_continue_rcu(e, &set->list, list) { 184 dest = e->dest; 185 if (dest->flags & IP_VS_DEST_F_OVERLOAD) 186 continue; 187 188 doh = ip_vs_dest_conn_overhead(dest); 189 if (((__s64)loh * atomic_read(&dest->weight) > 190 (__s64)doh * atomic_read(&least->weight)) 191 && (dest->flags & IP_VS_DEST_F_AVAILABLE)) { 192 least = dest; 193 loh = doh; 194 } 195 } 196 197 IP_VS_DBG_BUF(6, "%s(): server %s:%d " 198 "activeconns %d refcnt %d weight %d overhead %d\n", 199 __func__, 200 IP_VS_DBG_ADDR(least->af, &least->addr), 201 ntohs(least->port), 202 atomic_read(&least->activeconns), 203 refcount_read(&least->refcnt), 204 atomic_read(&least->weight), loh); 205 return least; 206} 207 208 209/* get weighted most-connection node in the destination set */ 210static inline struct ip_vs_dest *ip_vs_dest_set_max(struct ip_vs_dest_set *set) 211{ 212 struct ip_vs_dest_set_elem *e; 213 struct ip_vs_dest *dest, *most; 214 int moh, doh; 215 216 if (set == NULL) 217 return NULL; 218 219 /* select the first destination server, whose weight > 0 */ 220 list_for_each_entry(e, &set->list, list) { 221 most = e->dest; 222 if (atomic_read(&most->weight) > 0) { 223 moh = ip_vs_dest_conn_overhead(most); 224 goto nextstage; 225 } 226 } 227 return NULL; 228 229 /* find the destination with the weighted most load */ 230 nextstage: 231 list_for_each_entry_continue(e, &set->list, list) { 232 dest = e->dest; 233 doh = ip_vs_dest_conn_overhead(dest); 234 /* moh/mw < doh/dw ==> moh*dw < doh*mw, where mw,dw>0 */ 235 if (((__s64)moh * atomic_read(&dest->weight) < 236 (__s64)doh * atomic_read(&most->weight)) 237 && (atomic_read(&dest->weight) > 0)) { 238 most = dest; 239 moh = doh; 240 } 241 } 242 243 IP_VS_DBG_BUF(6, "%s(): server %s:%d " 244 "activeconns %d refcnt %d weight %d overhead %d\n", 245 __func__, 246 IP_VS_DBG_ADDR(most->af, &most->addr), ntohs(most->port), 247 atomic_read(&most->activeconns), 248 refcount_read(&most->refcnt), 249 atomic_read(&most->weight), moh); 250 return most; 251} 252 253 254/* 255 * IPVS lblcr entry represents an association between destination 256 * IP address and its destination server set 257 */ 258struct ip_vs_lblcr_entry { 259 struct hlist_node list; 260 int af; /* address family */ 261 union nf_inet_addr addr; /* destination IP address */ 262 struct ip_vs_dest_set set; /* destination server set */ 263 unsigned long lastuse; /* last used time */ 264 struct rcu_head rcu_head; 265}; 266 267 268/* 269 * IPVS lblcr hash table 270 */ 271struct ip_vs_lblcr_table { 272 struct rcu_head rcu_head; 273 struct hlist_head bucket[IP_VS_LBLCR_TAB_SIZE]; /* hash bucket */ 274 atomic_t entries; /* number of entries */ 275 int max_size; /* maximum size of entries */ 276 struct timer_list periodic_timer; /* collect stale entries */ 277 struct ip_vs_service *svc; /* pointer back to service */ 278 int rover; /* rover for expire check */ 279 int counter; /* counter for no expire */ 280 bool dead; 281}; 282 283 284#ifdef CONFIG_SYSCTL 285/* 286 * IPVS LBLCR sysctl table 287 */ 288 289static struct ctl_table vs_vars_table[] = { 290 { 291 .procname = "lblcr_expiration", 292 .data = NULL, 293 .maxlen = sizeof(int), 294 .mode = 0644, 295 .proc_handler = proc_dointvec_jiffies, 296 }, 297 { } 298}; 299#endif 300 301static inline void ip_vs_lblcr_free(struct ip_vs_lblcr_entry *en) 302{ 303 hlist_del_rcu(&en->list); 304 ip_vs_dest_set_eraseall(&en->set); 305 kfree_rcu(en, rcu_head); 306} 307 308 309/* 310 * Returns hash value for IPVS LBLCR entry 311 */ 312static inline unsigned int 313ip_vs_lblcr_hashkey(int af, const union nf_inet_addr *addr) 314{ 315 __be32 addr_fold = addr->ip; 316 317#ifdef CONFIG_IP_VS_IPV6 318 if (af == AF_INET6) 319 addr_fold = addr->ip6[0]^addr->ip6[1]^ 320 addr->ip6[2]^addr->ip6[3]; 321#endif 322 return hash_32(ntohl(addr_fold), IP_VS_LBLCR_TAB_BITS); 323} 324 325 326/* 327 * Hash an entry in the ip_vs_lblcr_table. 328 * returns bool success. 329 */ 330static void 331ip_vs_lblcr_hash(struct ip_vs_lblcr_table *tbl, struct ip_vs_lblcr_entry *en) 332{ 333 unsigned int hash = ip_vs_lblcr_hashkey(en->af, &en->addr); 334 335 hlist_add_head_rcu(&en->list, &tbl->bucket[hash]); 336 atomic_inc(&tbl->entries); 337} 338 339 340/* Get ip_vs_lblcr_entry associated with supplied parameters. */ 341static inline struct ip_vs_lblcr_entry * 342ip_vs_lblcr_get(int af, struct ip_vs_lblcr_table *tbl, 343 const union nf_inet_addr *addr) 344{ 345 unsigned int hash = ip_vs_lblcr_hashkey(af, addr); 346 struct ip_vs_lblcr_entry *en; 347 348 hlist_for_each_entry_rcu(en, &tbl->bucket[hash], list) 349 if (ip_vs_addr_equal(af, &en->addr, addr)) 350 return en; 351 352 return NULL; 353} 354 355 356/* 357 * Create or update an ip_vs_lblcr_entry, which is a mapping of a destination 358 * IP address to a server. Called under spin lock. 359 */ 360static inline struct ip_vs_lblcr_entry * 361ip_vs_lblcr_new(struct ip_vs_lblcr_table *tbl, const union nf_inet_addr *daddr, 362 u16 af, struct ip_vs_dest *dest) 363{ 364 struct ip_vs_lblcr_entry *en; 365 366 en = ip_vs_lblcr_get(af, tbl, daddr); 367 if (!en) { 368 en = kmalloc(sizeof(*en), GFP_ATOMIC); 369 if (!en) 370 return NULL; 371 372 en->af = af; 373 ip_vs_addr_copy(af, &en->addr, daddr); 374 en->lastuse = jiffies; 375 376 /* initialize its dest set */ 377 atomic_set(&(en->set.size), 0); 378 INIT_LIST_HEAD(&en->set.list); 379 380 ip_vs_dest_set_insert(&en->set, dest, false); 381 382 ip_vs_lblcr_hash(tbl, en); 383 return en; 384 } 385 386 ip_vs_dest_set_insert(&en->set, dest, true); 387 388 return en; 389} 390 391 392/* 393 * Flush all the entries of the specified table. 394 */ 395static void ip_vs_lblcr_flush(struct ip_vs_service *svc) 396{ 397 struct ip_vs_lblcr_table *tbl = svc->sched_data; 398 int i; 399 struct ip_vs_lblcr_entry *en; 400 struct hlist_node *next; 401 402 spin_lock_bh(&svc->sched_lock); 403 tbl->dead = true; 404 for (i = 0; i < IP_VS_LBLCR_TAB_SIZE; i++) { 405 hlist_for_each_entry_safe(en, next, &tbl->bucket[i], list) { 406 ip_vs_lblcr_free(en); 407 } 408 } 409 spin_unlock_bh(&svc->sched_lock); 410} 411 412static int sysctl_lblcr_expiration(struct ip_vs_service *svc) 413{ 414#ifdef CONFIG_SYSCTL 415 return svc->ipvs->sysctl_lblcr_expiration; 416#else 417 return DEFAULT_EXPIRATION; 418#endif 419} 420 421static inline void ip_vs_lblcr_full_check(struct ip_vs_service *svc) 422{ 423 struct ip_vs_lblcr_table *tbl = svc->sched_data; 424 unsigned long now = jiffies; 425 int i, j; 426 struct ip_vs_lblcr_entry *en; 427 struct hlist_node *next; 428 429 for (i = 0, j = tbl->rover; i < IP_VS_LBLCR_TAB_SIZE; i++) { 430 j = (j + 1) & IP_VS_LBLCR_TAB_MASK; 431 432 spin_lock(&svc->sched_lock); 433 hlist_for_each_entry_safe(en, next, &tbl->bucket[j], list) { 434 if (time_after(en->lastuse + 435 sysctl_lblcr_expiration(svc), now)) 436 continue; 437 438 ip_vs_lblcr_free(en); 439 atomic_dec(&tbl->entries); 440 } 441 spin_unlock(&svc->sched_lock); 442 } 443 tbl->rover = j; 444} 445 446 447/* 448 * Periodical timer handler for IPVS lblcr table 449 * It is used to collect stale entries when the number of entries 450 * exceeds the maximum size of the table. 451 * 452 * Fixme: we probably need more complicated algorithm to collect 453 * entries that have not been used for a long time even 454 * if the number of entries doesn't exceed the maximum size 455 * of the table. 456 * The full expiration check is for this purpose now. 457 */ 458static void ip_vs_lblcr_check_expire(struct timer_list *t) 459{ 460 struct ip_vs_lblcr_table *tbl = from_timer(tbl, t, periodic_timer); 461 struct ip_vs_service *svc = tbl->svc; 462 unsigned long now = jiffies; 463 int goal; 464 int i, j; 465 struct ip_vs_lblcr_entry *en; 466 struct hlist_node *next; 467 468 if ((tbl->counter % COUNT_FOR_FULL_EXPIRATION) == 0) { 469 /* do full expiration check */ 470 ip_vs_lblcr_full_check(svc); 471 tbl->counter = 1; 472 goto out; 473 } 474 475 if (atomic_read(&tbl->entries) <= tbl->max_size) { 476 tbl->counter++; 477 goto out; 478 } 479 480 goal = (atomic_read(&tbl->entries) - tbl->max_size)*4/3; 481 if (goal > tbl->max_size/2) 482 goal = tbl->max_size/2; 483 484 for (i = 0, j = tbl->rover; i < IP_VS_LBLCR_TAB_SIZE; i++) { 485 j = (j + 1) & IP_VS_LBLCR_TAB_MASK; 486 487 spin_lock(&svc->sched_lock); 488 hlist_for_each_entry_safe(en, next, &tbl->bucket[j], list) { 489 if (time_before(now, en->lastuse+ENTRY_TIMEOUT)) 490 continue; 491 492 ip_vs_lblcr_free(en); 493 atomic_dec(&tbl->entries); 494 goal--; 495 } 496 spin_unlock(&svc->sched_lock); 497 if (goal <= 0) 498 break; 499 } 500 tbl->rover = j; 501 502 out: 503 mod_timer(&tbl->periodic_timer, jiffies+CHECK_EXPIRE_INTERVAL); 504} 505 506static int ip_vs_lblcr_init_svc(struct ip_vs_service *svc) 507{ 508 int i; 509 struct ip_vs_lblcr_table *tbl; 510 511 /* 512 * Allocate the ip_vs_lblcr_table for this service 513 */ 514 tbl = kmalloc(sizeof(*tbl), GFP_KERNEL); 515 if (tbl == NULL) 516 return -ENOMEM; 517 518 svc->sched_data = tbl; 519 IP_VS_DBG(6, "LBLCR hash table (memory=%zdbytes) allocated for " 520 "current service\n", sizeof(*tbl)); 521 522 /* 523 * Initialize the hash buckets 524 */ 525 for (i = 0; i < IP_VS_LBLCR_TAB_SIZE; i++) { 526 INIT_HLIST_HEAD(&tbl->bucket[i]); 527 } 528 tbl->max_size = IP_VS_LBLCR_TAB_SIZE*16; 529 tbl->rover = 0; 530 tbl->counter = 1; 531 tbl->dead = false; 532 tbl->svc = svc; 533 atomic_set(&tbl->entries, 0); 534 535 /* 536 * Hook periodic timer for garbage collection 537 */ 538 timer_setup(&tbl->periodic_timer, ip_vs_lblcr_check_expire, 0); 539 mod_timer(&tbl->periodic_timer, jiffies + CHECK_EXPIRE_INTERVAL); 540 541 return 0; 542} 543 544 545static void ip_vs_lblcr_done_svc(struct ip_vs_service *svc) 546{ 547 struct ip_vs_lblcr_table *tbl = svc->sched_data; 548 549 /* remove periodic timer */ 550 timer_shutdown_sync(&tbl->periodic_timer); 551 552 /* got to clean up table entries here */ 553 ip_vs_lblcr_flush(svc); 554 555 /* release the table itself */ 556 kfree_rcu(tbl, rcu_head); 557 IP_VS_DBG(6, "LBLCR hash table (memory=%zdbytes) released\n", 558 sizeof(*tbl)); 559} 560 561 562static inline struct ip_vs_dest * 563__ip_vs_lblcr_schedule(struct ip_vs_service *svc) 564{ 565 struct ip_vs_dest *dest, *least; 566 int loh, doh; 567 568 /* 569 * We use the following formula to estimate the load: 570 * (dest overhead) / dest->weight 571 * 572 * Remember -- no floats in kernel mode!!! 573 * The comparison of h1*w2 > h2*w1 is equivalent to that of 574 * h1/w1 > h2/w2 575 * if every weight is larger than zero. 576 * 577 * The server with weight=0 is quiesced and will not receive any 578 * new connection. 579 */ 580 list_for_each_entry_rcu(dest, &svc->destinations, n_list) { 581 if (dest->flags & IP_VS_DEST_F_OVERLOAD) 582 continue; 583 584 if (atomic_read(&dest->weight) > 0) { 585 least = dest; 586 loh = ip_vs_dest_conn_overhead(least); 587 goto nextstage; 588 } 589 } 590 return NULL; 591 592 /* 593 * Find the destination with the least load. 594 */ 595 nextstage: 596 list_for_each_entry_continue_rcu(dest, &svc->destinations, n_list) { 597 if (dest->flags & IP_VS_DEST_F_OVERLOAD) 598 continue; 599 600 doh = ip_vs_dest_conn_overhead(dest); 601 if ((__s64)loh * atomic_read(&dest->weight) > 602 (__s64)doh * atomic_read(&least->weight)) { 603 least = dest; 604 loh = doh; 605 } 606 } 607 608 IP_VS_DBG_BUF(6, "LBLCR: server %s:%d " 609 "activeconns %d refcnt %d weight %d overhead %d\n", 610 IP_VS_DBG_ADDR(least->af, &least->addr), 611 ntohs(least->port), 612 atomic_read(&least->activeconns), 613 refcount_read(&least->refcnt), 614 atomic_read(&least->weight), loh); 615 616 return least; 617} 618 619 620/* 621 * If this destination server is overloaded and there is a less loaded 622 * server, then return true. 623 */ 624static inline int 625is_overloaded(struct ip_vs_dest *dest, struct ip_vs_service *svc) 626{ 627 if (atomic_read(&dest->activeconns) > atomic_read(&dest->weight)) { 628 struct ip_vs_dest *d; 629 630 list_for_each_entry_rcu(d, &svc->destinations, n_list) { 631 if (atomic_read(&d->activeconns)*2 632 < atomic_read(&d->weight)) { 633 return 1; 634 } 635 } 636 } 637 return 0; 638} 639 640 641/* 642 * Locality-Based (weighted) Least-Connection scheduling 643 */ 644static struct ip_vs_dest * 645ip_vs_lblcr_schedule(struct ip_vs_service *svc, const struct sk_buff *skb, 646 struct ip_vs_iphdr *iph) 647{ 648 struct ip_vs_lblcr_table *tbl = svc->sched_data; 649 struct ip_vs_dest *dest; 650 struct ip_vs_lblcr_entry *en; 651 652 IP_VS_DBG(6, "%s(): Scheduling...\n", __func__); 653 654 /* First look in our cache */ 655 en = ip_vs_lblcr_get(svc->af, tbl, &iph->daddr); 656 if (en) { 657 en->lastuse = jiffies; 658 659 /* Get the least loaded destination */ 660 dest = ip_vs_dest_set_min(&en->set); 661 662 /* More than one destination + enough time passed by, cleanup */ 663 if (atomic_read(&en->set.size) > 1 && 664 time_after(jiffies, en->set.lastmod + 665 sysctl_lblcr_expiration(svc))) { 666 spin_lock_bh(&svc->sched_lock); 667 if (atomic_read(&en->set.size) > 1) { 668 struct ip_vs_dest *m; 669 670 m = ip_vs_dest_set_max(&en->set); 671 if (m) 672 ip_vs_dest_set_erase(&en->set, m); 673 } 674 spin_unlock_bh(&svc->sched_lock); 675 } 676 677 /* If the destination is not overloaded, use it */ 678 if (dest && !is_overloaded(dest, svc)) 679 goto out; 680 681 /* The cache entry is invalid, time to schedule */ 682 dest = __ip_vs_lblcr_schedule(svc); 683 if (!dest) { 684 ip_vs_scheduler_err(svc, "no destination available"); 685 return NULL; 686 } 687 688 /* Update our cache entry */ 689 spin_lock_bh(&svc->sched_lock); 690 if (!tbl->dead) 691 ip_vs_dest_set_insert(&en->set, dest, true); 692 spin_unlock_bh(&svc->sched_lock); 693 goto out; 694 } 695 696 /* No cache entry, time to schedule */ 697 dest = __ip_vs_lblcr_schedule(svc); 698 if (!dest) { 699 IP_VS_DBG(1, "no destination available\n"); 700 return NULL; 701 } 702 703 /* If we fail to create a cache entry, we'll just use the valid dest */ 704 spin_lock_bh(&svc->sched_lock); 705 if (!tbl->dead) 706 ip_vs_lblcr_new(tbl, &iph->daddr, svc->af, dest); 707 spin_unlock_bh(&svc->sched_lock); 708 709out: 710 IP_VS_DBG_BUF(6, "LBLCR: destination IP address %s --> server %s:%d\n", 711 IP_VS_DBG_ADDR(svc->af, &iph->daddr), 712 IP_VS_DBG_ADDR(dest->af, &dest->addr), ntohs(dest->port)); 713 714 return dest; 715} 716 717 718/* 719 * IPVS LBLCR Scheduler structure 720 */ 721static struct ip_vs_scheduler ip_vs_lblcr_scheduler = 722{ 723 .name = "lblcr", 724 .refcnt = ATOMIC_INIT(0), 725 .module = THIS_MODULE, 726 .n_list = LIST_HEAD_INIT(ip_vs_lblcr_scheduler.n_list), 727 .init_service = ip_vs_lblcr_init_svc, 728 .done_service = ip_vs_lblcr_done_svc, 729 .schedule = ip_vs_lblcr_schedule, 730}; 731 732/* 733 * per netns init. 734 */ 735#ifdef CONFIG_SYSCTL 736static int __net_init __ip_vs_lblcr_init(struct net *net) 737{ 738 struct netns_ipvs *ipvs = net_ipvs(net); 739 size_t vars_table_size = ARRAY_SIZE(vs_vars_table); 740 741 if (!ipvs) 742 return -ENOENT; 743 744 if (!net_eq(net, &init_net)) { 745 ipvs->lblcr_ctl_table = kmemdup(vs_vars_table, 746 sizeof(vs_vars_table), 747 GFP_KERNEL); 748 if (ipvs->lblcr_ctl_table == NULL) 749 return -ENOMEM; 750 751 /* Don't export sysctls to unprivileged users */ 752 if (net->user_ns != &init_user_ns) { 753 ipvs->lblcr_ctl_table[0].procname = NULL; 754 vars_table_size = 0; 755 } 756 } else 757 ipvs->lblcr_ctl_table = vs_vars_table; 758 ipvs->sysctl_lblcr_expiration = DEFAULT_EXPIRATION; 759 ipvs->lblcr_ctl_table[0].data = &ipvs->sysctl_lblcr_expiration; 760 761 ipvs->lblcr_ctl_header = register_net_sysctl_sz(net, "net/ipv4/vs", 762 ipvs->lblcr_ctl_table, 763 vars_table_size); 764 if (!ipvs->lblcr_ctl_header) { 765 if (!net_eq(net, &init_net)) 766 kfree(ipvs->lblcr_ctl_table); 767 return -ENOMEM; 768 } 769 770 return 0; 771} 772 773static void __net_exit __ip_vs_lblcr_exit(struct net *net) 774{ 775 struct netns_ipvs *ipvs = net_ipvs(net); 776 777 unregister_net_sysctl_table(ipvs->lblcr_ctl_header); 778 779 if (!net_eq(net, &init_net)) 780 kfree(ipvs->lblcr_ctl_table); 781} 782 783#else 784 785static int __net_init __ip_vs_lblcr_init(struct net *net) { return 0; } 786static void __net_exit __ip_vs_lblcr_exit(struct net *net) { } 787 788#endif 789 790static struct pernet_operations ip_vs_lblcr_ops = { 791 .init = __ip_vs_lblcr_init, 792 .exit = __ip_vs_lblcr_exit, 793}; 794 795static int __init ip_vs_lblcr_init(void) 796{ 797 int ret; 798 799 ret = register_pernet_subsys(&ip_vs_lblcr_ops); 800 if (ret) 801 return ret; 802 803 ret = register_ip_vs_scheduler(&ip_vs_lblcr_scheduler); 804 if (ret) 805 unregister_pernet_subsys(&ip_vs_lblcr_ops); 806 return ret; 807} 808 809static void __exit ip_vs_lblcr_cleanup(void) 810{ 811 unregister_ip_vs_scheduler(&ip_vs_lblcr_scheduler); 812 unregister_pernet_subsys(&ip_vs_lblcr_ops); 813 rcu_barrier(); 814} 815 816 817module_init(ip_vs_lblcr_init); 818module_exit(ip_vs_lblcr_cleanup); 819MODULE_LICENSE("GPL"); 820MODULE_DESCRIPTION("ipvs locality-based least-connection with replication scheduler"); 821