diff options
Diffstat (limited to 'net/tipc/name_table.c')
| -rw-r--r-- | net/tipc/name_table.c | 1176 |
1 files changed, 1176 insertions, 0 deletions
diff --git a/net/tipc/name_table.c b/net/tipc/name_table.c new file mode 100644 index 000000000..54c5328f4 --- /dev/null +++ b/net/tipc/name_table.c @@ -0,0 +1,1176 @@ +/* + * net/tipc/name_table.c: TIPC name table code + * + * Copyright (c) 2000-2006, 2014-2018, Ericsson AB + * Copyright (c) 2004-2008, 2010-2014, Wind River Systems + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the names of the copyright holders nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * Alternatively, this software may be distributed under the terms of the + * GNU General Public License ("GPL") version 2 as published by the Free + * Software Foundation. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +#include <net/sock.h> +#include <linux/list_sort.h> +#include <linux/rbtree_augmented.h> +#include "core.h" +#include "netlink.h" +#include "name_table.h" +#include "name_distr.h" +#include "subscr.h" +#include "bcast.h" +#include "addr.h" +#include "node.h" +#include "group.h" + +/** + * struct service_range - container for all bindings of a service range + * @lower: service range lower bound + * @upper: service range upper bound + * @tree_node: member of service range RB tree + * @max: largest 'upper' in this node subtree + * @local_publ: list of identical publications made from this node + * Used by closest_first lookup and multicast lookup algorithm + * @all_publ: all publications identical to this one, whatever node and scope + * Used by round-robin lookup algorithm + */ +struct service_range { + u32 lower; + u32 upper; + struct rb_node tree_node; + u32 max; + struct list_head local_publ; + struct list_head all_publ; +}; + +/** + * struct tipc_service - container for all published instances of a service type + * @type: 32 bit 'type' value for service + * @publ_cnt: increasing counter for publications in this service + * @ranges: rb tree containing all service ranges for this service + * @service_list: links to adjacent name ranges in hash chain + * @subscriptions: list of subscriptions for this service type + * @lock: spinlock controlling access to pertaining service ranges/publications + * @rcu: RCU callback head used for deferred freeing + */ +struct tipc_service { + u32 type; + u32 publ_cnt; + struct rb_root ranges; + struct hlist_node service_list; + struct list_head subscriptions; + spinlock_t lock; /* Covers service range list */ + struct rcu_head rcu; +}; + +#define service_range_upper(sr) ((sr)->upper) +RB_DECLARE_CALLBACKS_MAX(static, sr_callbacks, + struct service_range, tree_node, u32, max, + service_range_upper) + +#define service_range_entry(rbtree_node) \ + (container_of(rbtree_node, struct service_range, tree_node)) + +#define service_range_overlap(sr, start, end) \ + ((sr)->lower <= (end) && (sr)->upper >= (start)) + +/** + * service_range_foreach_match - iterate over tipc service rbtree for each + * range match + * @sr: the service range pointer as a loop cursor + * @sc: the pointer to tipc service which holds the service range rbtree + * @start, end: the range (end >= start) for matching + */ +#define service_range_foreach_match(sr, sc, start, end) \ + for (sr = service_range_match_first((sc)->ranges.rb_node, \ + start, \ + end); \ + sr; \ + sr = service_range_match_next(&(sr)->tree_node, \ + start, \ + end)) + +/** + * service_range_match_first - find first service range matching a range + * @n: the root node of service range rbtree for searching + * @start, end: the range (end >= start) for matching + * + * Return: the leftmost service range node in the rbtree that overlaps the + * specific range if any. Otherwise, returns NULL. + */ +static struct service_range *service_range_match_first(struct rb_node *n, + u32 start, u32 end) +{ + struct service_range *sr; + struct rb_node *l, *r; + + /* Non overlaps in tree at all? */ + if (!n || service_range_entry(n)->max < start) + return NULL; + + while (n) { + l = n->rb_left; + if (l && service_range_entry(l)->max >= start) { + /* A leftmost overlap range node must be one in the left + * subtree. If not, it has lower > end, then nodes on + * the right side cannot satisfy the condition either. + */ + n = l; + continue; + } + + /* No one in the left subtree can match, return if this node is + * an overlap i.e. leftmost. + */ + sr = service_range_entry(n); + if (service_range_overlap(sr, start, end)) + return sr; + + /* Ok, try to lookup on the right side */ + r = n->rb_right; + if (sr->lower <= end && + r && service_range_entry(r)->max >= start) { + n = r; + continue; + } + break; + } + + return NULL; +} + +/** + * service_range_match_next - find next service range matching a range + * @n: a node in service range rbtree from which the searching starts + * @start, end: the range (end >= start) for matching + * + * Return: the next service range node to the given node in the rbtree that + * overlaps the specific range if any. Otherwise, returns NULL. + */ +static struct service_range *service_range_match_next(struct rb_node *n, + u32 start, u32 end) +{ + struct service_range *sr; + struct rb_node *p, *r; + + while (n) { + r = n->rb_right; + if (r && service_range_entry(r)->max >= start) + /* A next overlap range node must be one in the right + * subtree. If not, it has lower > end, then any next + * successor (- an ancestor) of this node cannot + * satisfy the condition either. + */ + return service_range_match_first(r, start, end); + + /* No one in the right subtree can match, go up to find an + * ancestor of this node which is parent of a left-hand child. + */ + while ((p = rb_parent(n)) && n == p->rb_right) + n = p; + if (!p) + break; + + /* Return if this ancestor is an overlap */ + sr = service_range_entry(p); + if (service_range_overlap(sr, start, end)) + return sr; + + /* Ok, try to lookup more from this ancestor */ + if (sr->lower <= end) { + n = p; + continue; + } + break; + } + + return NULL; +} + +static int hash(int x) +{ + return x & (TIPC_NAMETBL_SIZE - 1); +} + +/** + * tipc_publ_create - create a publication structure + */ +static struct publication *tipc_publ_create(u32 type, u32 lower, u32 upper, + u32 scope, u32 node, u32 port, + u32 key) +{ + struct publication *publ = kzalloc(sizeof(*publ), GFP_ATOMIC); + + if (!publ) + return NULL; + + publ->type = type; + publ->lower = lower; + publ->upper = upper; + publ->scope = scope; + publ->node = node; + publ->port = port; + publ->key = key; + INIT_LIST_HEAD(&publ->binding_sock); + INIT_LIST_HEAD(&publ->binding_node); + INIT_LIST_HEAD(&publ->local_publ); + INIT_LIST_HEAD(&publ->all_publ); + INIT_LIST_HEAD(&publ->list); + return publ; +} + +/** + * tipc_service_create - create a service structure for the specified 'type' + * + * Allocates a single range structure and sets it to all 0's. + */ +static struct tipc_service *tipc_service_create(u32 type, struct hlist_head *hd) +{ + struct tipc_service *service = kzalloc(sizeof(*service), GFP_ATOMIC); + + if (!service) { + pr_warn("Service creation failed, no memory\n"); + return NULL; + } + + spin_lock_init(&service->lock); + service->type = type; + service->ranges = RB_ROOT; + INIT_HLIST_NODE(&service->service_list); + INIT_LIST_HEAD(&service->subscriptions); + hlist_add_head_rcu(&service->service_list, hd); + return service; +} + +/* tipc_service_find_range - find service range matching publication parameters + */ +static struct service_range *tipc_service_find_range(struct tipc_service *sc, + u32 lower, u32 upper) +{ + struct service_range *sr; + + service_range_foreach_match(sr, sc, lower, upper) { + /* Look for exact match */ + if (sr->lower == lower && sr->upper == upper) + return sr; + } + + return NULL; +} + +static struct service_range *tipc_service_create_range(struct tipc_service *sc, + u32 lower, u32 upper) +{ + struct rb_node **n, *parent = NULL; + struct service_range *sr; + + n = &sc->ranges.rb_node; + while (*n) { + parent = *n; + sr = service_range_entry(parent); + if (lower == sr->lower && upper == sr->upper) + return sr; + if (sr->max < upper) + sr->max = upper; + if (lower <= sr->lower) + n = &parent->rb_left; + else + n = &parent->rb_right; + } + sr = kzalloc(sizeof(*sr), GFP_ATOMIC); + if (!sr) + return NULL; + sr->lower = lower; + sr->upper = upper; + sr->max = upper; + INIT_LIST_HEAD(&sr->local_publ); + INIT_LIST_HEAD(&sr->all_publ); + rb_link_node(&sr->tree_node, parent, n); + rb_insert_augmented(&sr->tree_node, &sc->ranges, &sr_callbacks); + return sr; +} + +static struct publication *tipc_service_insert_publ(struct net *net, + struct tipc_service *sc, + u32 type, u32 lower, + u32 upper, u32 scope, + u32 node, u32 port, + u32 key) +{ + struct tipc_subscription *sub, *tmp; + struct service_range *sr; + struct publication *p; + bool first = false; + + sr = tipc_service_create_range(sc, lower, upper); + if (!sr) + goto err; + + first = list_empty(&sr->all_publ); + + /* Return if the publication already exists */ + list_for_each_entry(p, &sr->all_publ, all_publ) { + if (p->key == key && (!p->node || p->node == node)) + return NULL; + } + + /* Create and insert publication */ + p = tipc_publ_create(type, lower, upper, scope, node, port, key); + if (!p) + goto err; + /* Suppose there shouldn't be a huge gap btw publs i.e. >INT_MAX */ + p->id = sc->publ_cnt++; + if (in_own_node(net, node)) + list_add(&p->local_publ, &sr->local_publ); + list_add(&p->all_publ, &sr->all_publ); + + /* Any subscriptions waiting for notification? */ + list_for_each_entry_safe(sub, tmp, &sc->subscriptions, service_list) { + tipc_sub_report_overlap(sub, p->lower, p->upper, TIPC_PUBLISHED, + p->port, p->node, p->scope, first); + } + return p; +err: + pr_warn("Failed to bind to %u,%u,%u, no memory\n", type, lower, upper); + return NULL; +} + +/** + * tipc_service_remove_publ - remove a publication from a service + */ +static struct publication *tipc_service_remove_publ(struct service_range *sr, + u32 node, u32 key) +{ + struct publication *p; + + list_for_each_entry(p, &sr->all_publ, all_publ) { + if (p->key != key || (node && node != p->node)) + continue; + list_del(&p->all_publ); + list_del(&p->local_publ); + return p; + } + return NULL; +} + +/** + * Code reused: time_after32() for the same purpose + */ +#define publication_after(pa, pb) time_after32((pa)->id, (pb)->id) +static int tipc_publ_sort(void *priv, const struct list_head *a, + const struct list_head *b) +{ + struct publication *pa, *pb; + + pa = container_of(a, struct publication, list); + pb = container_of(b, struct publication, list); + return publication_after(pa, pb); +} + +/** + * tipc_service_subscribe - attach a subscription, and optionally + * issue the prescribed number of events if there is any service + * range overlapping with the requested range + */ +static void tipc_service_subscribe(struct tipc_service *service, + struct tipc_subscription *sub) +{ + struct tipc_subscr *sb = &sub->evt.s; + struct publication *p, *first, *tmp; + struct list_head publ_list; + struct service_range *sr; + struct tipc_name_seq ns; + u32 filter; + + ns.type = tipc_sub_read(sb, seq.type); + ns.lower = tipc_sub_read(sb, seq.lower); + ns.upper = tipc_sub_read(sb, seq.upper); + filter = tipc_sub_read(sb, filter); + + tipc_sub_get(sub); + list_add(&sub->service_list, &service->subscriptions); + + if (filter & TIPC_SUB_NO_STATUS) + return; + + INIT_LIST_HEAD(&publ_list); + service_range_foreach_match(sr, service, ns.lower, ns.upper) { + first = NULL; + list_for_each_entry(p, &sr->all_publ, all_publ) { + if (filter & TIPC_SUB_PORTS) + list_add_tail(&p->list, &publ_list); + else if (!first || publication_after(first, p)) + /* Pick this range's *first* publication */ + first = p; + } + if (first) + list_add_tail(&first->list, &publ_list); + } + + /* Sort the publications before reporting */ + list_sort(NULL, &publ_list, tipc_publ_sort); + list_for_each_entry_safe(p, tmp, &publ_list, list) { + tipc_sub_report_overlap(sub, p->lower, p->upper, + TIPC_PUBLISHED, p->port, p->node, + p->scope, true); + list_del_init(&p->list); + } +} + +static struct tipc_service *tipc_service_find(struct net *net, u32 type) +{ + struct name_table *nt = tipc_name_table(net); + struct hlist_head *service_head; + struct tipc_service *service; + + service_head = &nt->services[hash(type)]; + hlist_for_each_entry_rcu(service, service_head, service_list) { + if (service->type == type) + return service; + } + return NULL; +}; + +struct publication *tipc_nametbl_insert_publ(struct net *net, u32 type, + u32 lower, u32 upper, + u32 scope, u32 node, + u32 port, u32 key) +{ + struct name_table *nt = tipc_name_table(net); + struct tipc_service *sc; + struct publication *p; + + if (scope > TIPC_NODE_SCOPE || lower > upper) { + pr_debug("Failed to bind illegal {%u,%u,%u} with scope %u\n", + type, lower, upper, scope); + return NULL; + } + sc = tipc_service_find(net, type); + if (!sc) + sc = tipc_service_create(type, &nt->services[hash(type)]); + if (!sc) + return NULL; + + spin_lock_bh(&sc->lock); + p = tipc_service_insert_publ(net, sc, type, lower, upper, + scope, node, port, key); + spin_unlock_bh(&sc->lock); + return p; +} + +struct publication *tipc_nametbl_remove_publ(struct net *net, u32 type, + u32 lower, u32 upper, + u32 node, u32 key) +{ + struct tipc_service *sc = tipc_service_find(net, type); + struct tipc_subscription *sub, *tmp; + struct service_range *sr = NULL; + struct publication *p = NULL; + bool last; + + if (!sc) + return NULL; + + spin_lock_bh(&sc->lock); + sr = tipc_service_find_range(sc, lower, upper); + if (!sr) + goto exit; + p = tipc_service_remove_publ(sr, node, key); + if (!p) + goto exit; + + /* Notify any waiting subscriptions */ + last = list_empty(&sr->all_publ); + list_for_each_entry_safe(sub, tmp, &sc->subscriptions, service_list) { + tipc_sub_report_overlap(sub, lower, upper, TIPC_WITHDRAWN, + p->port, node, p->scope, last); + } + + /* Remove service range item if this was its last publication */ + if (list_empty(&sr->all_publ)) { + rb_erase_augmented(&sr->tree_node, &sc->ranges, &sr_callbacks); + kfree(sr); + } + + /* Delete service item if this no more publications and subscriptions */ + if (RB_EMPTY_ROOT(&sc->ranges) && list_empty(&sc->subscriptions)) { + hlist_del_init_rcu(&sc->service_list); + kfree_rcu(sc, rcu); + } +exit: + spin_unlock_bh(&sc->lock); + return p; +} + +/** + * tipc_nametbl_translate - perform service instance to socket translation + * + * On entry, 'dnode' is the search domain used during translation. + * + * On exit: + * - if translation is deferred to another node, leave 'dnode' unchanged and + * return 0 + * - if translation is attempted and succeeds, set 'dnode' to the publishing + * node and return the published (non-zero) port number + * - if translation is attempted and fails, set 'dnode' to 0 and return 0 + * + * Note that for legacy users (node configured with Z.C.N address format) the + * 'closest-first' lookup algorithm must be maintained, i.e., if dnode is 0 + * we must look in the local binding list first + */ +u32 tipc_nametbl_translate(struct net *net, u32 type, u32 instance, u32 *dnode) +{ + struct tipc_net *tn = tipc_net(net); + bool legacy = tn->legacy_addr_format; + u32 self = tipc_own_addr(net); + struct service_range *sr; + struct tipc_service *sc; + struct list_head *list; + struct publication *p; + u32 port = 0; + u32 node = 0; + + if (!tipc_in_scope(legacy, *dnode, self)) + return 0; + + rcu_read_lock(); + sc = tipc_service_find(net, type); + if (unlikely(!sc)) + goto exit; + + spin_lock_bh(&sc->lock); + service_range_foreach_match(sr, sc, instance, instance) { + /* Select lookup algo: local, closest-first or round-robin */ + if (*dnode == self) { + list = &sr->local_publ; + if (list_empty(list)) + continue; + p = list_first_entry(list, struct publication, + local_publ); + list_move_tail(&p->local_publ, &sr->local_publ); + } else if (legacy && !*dnode && !list_empty(&sr->local_publ)) { + list = &sr->local_publ; + p = list_first_entry(list, struct publication, + local_publ); + list_move_tail(&p->local_publ, &sr->local_publ); + } else { + list = &sr->all_publ; + p = list_first_entry(list, struct publication, + all_publ); + list_move_tail(&p->all_publ, &sr->all_publ); + } + port = p->port; + node = p->node; + /* Todo: as for legacy, pick the first matching range only, a + * "true" round-robin will be performed as needed. + */ + break; + } + spin_unlock_bh(&sc->lock); + +exit: + rcu_read_unlock(); + *dnode = node; + return port; +} + +bool tipc_nametbl_lookup(struct net *net, u32 type, u32 instance, u32 scope, + struct list_head *dsts, int *dstcnt, u32 exclude, + bool all) +{ + u32 self = tipc_own_addr(net); + struct service_range *sr; + struct tipc_service *sc; + struct publication *p; + + *dstcnt = 0; + rcu_read_lock(); + sc = tipc_service_find(net, type); + if (unlikely(!sc)) + goto exit; + + spin_lock_bh(&sc->lock); + + /* Todo: a full search i.e. service_range_foreach_match() instead? */ + sr = service_range_match_first(sc->ranges.rb_node, instance, instance); + if (!sr) + goto no_match; + + list_for_each_entry(p, &sr->all_publ, all_publ) { + if (p->scope != scope) + continue; + if (p->port == exclude && p->node == self) + continue; + tipc_dest_push(dsts, p->node, p->port); + (*dstcnt)++; + if (all) + continue; + list_move_tail(&p->all_publ, &sr->all_publ); + break; + } +no_match: + spin_unlock_bh(&sc->lock); +exit: + rcu_read_unlock(); + return !list_empty(dsts); +} + +void tipc_nametbl_mc_lookup(struct net *net, u32 type, u32 lower, u32 upper, + u32 scope, bool exact, struct list_head *dports) +{ + struct service_range *sr; + struct tipc_service *sc; + struct publication *p; + + rcu_read_lock(); + sc = tipc_service_find(net, type); + if (!sc) + goto exit; + + spin_lock_bh(&sc->lock); + service_range_foreach_match(sr, sc, lower, upper) { + list_for_each_entry(p, &sr->local_publ, local_publ) { + if (p->scope == scope || (!exact && p->scope < scope)) + tipc_dest_push(dports, 0, p->port); + } + } + spin_unlock_bh(&sc->lock); +exit: + rcu_read_unlock(); +} + +/* tipc_nametbl_lookup_dst_nodes - find broadcast destination nodes + * - Creates list of nodes that overlap the given multicast address + * - Determines if any node local destinations overlap + */ +void tipc_nametbl_lookup_dst_nodes(struct net *net, u32 type, u32 lower, + u32 upper, struct tipc_nlist *nodes) +{ + struct service_range *sr; + struct tipc_service *sc; + struct publication *p; + + rcu_read_lock(); + sc = tipc_service_find(net, type); + if (!sc) + goto exit; + + spin_lock_bh(&sc->lock); + service_range_foreach_match(sr, sc, lower, upper) { + list_for_each_entry(p, &sr->all_publ, all_publ) { + tipc_nlist_add(nodes, p->node); + } + } + spin_unlock_bh(&sc->lock); +exit: + rcu_read_unlock(); +} + +/* tipc_nametbl_build_group - build list of communication group members + */ +void tipc_nametbl_build_group(struct net *net, struct tipc_group *grp, + u32 type, u32 scope) +{ + struct service_range *sr; + struct tipc_service *sc; + struct publication *p; + struct rb_node *n; + + rcu_read_lock(); + sc = tipc_service_find(net, type); + if (!sc) + goto exit; + + spin_lock_bh(&sc->lock); + for (n = rb_first(&sc->ranges); n; n = rb_next(n)) { + sr = container_of(n, struct service_range, tree_node); + list_for_each_entry(p, &sr->all_publ, all_publ) { + if (p->scope != scope) + continue; + tipc_group_add_member(grp, p->node, p->port, p->lower); + } + } + spin_unlock_bh(&sc->lock); +exit: + rcu_read_unlock(); +} + +/* tipc_nametbl_publish - add service binding to name table + */ +struct publication *tipc_nametbl_publish(struct net *net, u32 type, u32 lower, + u32 upper, u32 scope, u32 port, + u32 key) +{ + struct name_table *nt = tipc_name_table(net); + struct tipc_net *tn = tipc_net(net); + struct publication *p = NULL; + struct sk_buff *skb = NULL; + u32 rc_dests; + + spin_lock_bh(&tn->nametbl_lock); + + if (nt->local_publ_count >= TIPC_MAX_PUBL) { + pr_warn("Bind failed, max limit %u reached\n", TIPC_MAX_PUBL); + goto exit; + } + + p = tipc_nametbl_insert_publ(net, type, lower, upper, scope, + tipc_own_addr(net), port, key); + if (p) { + nt->local_publ_count++; + skb = tipc_named_publish(net, p); + } + rc_dests = nt->rc_dests; +exit: + spin_unlock_bh(&tn->nametbl_lock); + + if (skb) + tipc_node_broadcast(net, skb, rc_dests); + return p; + +} + +/** + * tipc_nametbl_withdraw - withdraw a service binding + */ +int tipc_nametbl_withdraw(struct net *net, u32 type, u32 lower, + u32 upper, u32 key) +{ + struct name_table *nt = tipc_name_table(net); + struct tipc_net *tn = tipc_net(net); + u32 self = tipc_own_addr(net); + struct sk_buff *skb = NULL; + struct publication *p; + u32 rc_dests; + + spin_lock_bh(&tn->nametbl_lock); + + p = tipc_nametbl_remove_publ(net, type, lower, upper, self, key); + if (p) { + nt->local_publ_count--; + skb = tipc_named_withdraw(net, p); + list_del_init(&p->binding_sock); + kfree_rcu(p, rcu); + } else { + pr_err("Failed to remove local publication {%u,%u,%u}/%u\n", + type, lower, upper, key); + } + rc_dests = nt->rc_dests; + spin_unlock_bh(&tn->nametbl_lock); + + if (skb) { + tipc_node_broadcast(net, skb, rc_dests); + return 1; + } + return 0; +} + +/** + * tipc_nametbl_subscribe - add a subscription object to the name table + */ +bool tipc_nametbl_subscribe(struct tipc_subscription *sub) +{ + struct name_table *nt = tipc_name_table(sub->net); + struct tipc_net *tn = tipc_net(sub->net); + struct tipc_subscr *s = &sub->evt.s; + u32 type = tipc_sub_read(s, seq.type); + struct tipc_service *sc; + bool res = true; + + spin_lock_bh(&tn->nametbl_lock); + sc = tipc_service_find(sub->net, type); + if (!sc) + sc = tipc_service_create(type, &nt->services[hash(type)]); + if (sc) { + spin_lock_bh(&sc->lock); + tipc_service_subscribe(sc, sub); + spin_unlock_bh(&sc->lock); + } else { + pr_warn("Failed to subscribe for {%u,%u,%u}\n", type, + tipc_sub_read(s, seq.lower), + tipc_sub_read(s, seq.upper)); + res = false; + } + spin_unlock_bh(&tn->nametbl_lock); + return res; +} + +/** + * tipc_nametbl_unsubscribe - remove a subscription object from name table + */ +void tipc_nametbl_unsubscribe(struct tipc_subscription *sub) +{ + struct tipc_net *tn = tipc_net(sub->net); + struct tipc_subscr *s = &sub->evt.s; + u32 type = tipc_sub_read(s, seq.type); + struct tipc_service *sc; + + spin_lock_bh(&tn->nametbl_lock); + sc = tipc_service_find(sub->net, type); + if (!sc) + goto exit; + + spin_lock_bh(&sc->lock); + list_del_init(&sub->service_list); + tipc_sub_put(sub); + + /* Delete service item if no more publications and subscriptions */ + if (RB_EMPTY_ROOT(&sc->ranges) && list_empty(&sc->subscriptions)) { + hlist_del_init_rcu(&sc->service_list); + kfree_rcu(sc, rcu); + } + spin_unlock_bh(&sc->lock); +exit: + spin_unlock_bh(&tn->nametbl_lock); +} + +int tipc_nametbl_init(struct net *net) +{ + struct tipc_net *tn = tipc_net(net); + struct name_table *nt; + int i; + + nt = kzalloc(sizeof(*nt), GFP_KERNEL); + if (!nt) + return -ENOMEM; + + for (i = 0; i < TIPC_NAMETBL_SIZE; i++) + INIT_HLIST_HEAD(&nt->services[i]); + + INIT_LIST_HEAD(&nt->node_scope); + INIT_LIST_HEAD(&nt->cluster_scope); + rwlock_init(&nt->cluster_scope_lock); + tn->nametbl = nt; + spin_lock_init(&tn->nametbl_lock); + return 0; +} + +/** + * tipc_service_delete - purge all publications for a service and delete it + */ +static void tipc_service_delete(struct net *net, struct tipc_service *sc) +{ + struct service_range *sr, *tmpr; + struct publication *p, *tmp; + + spin_lock_bh(&sc->lock); + rbtree_postorder_for_each_entry_safe(sr, tmpr, &sc->ranges, tree_node) { + list_for_each_entry_safe(p, tmp, &sr->all_publ, all_publ) { + tipc_service_remove_publ(sr, p->node, p->key); + kfree_rcu(p, rcu); + } + rb_erase_augmented(&sr->tree_node, &sc->ranges, &sr_callbacks); + kfree(sr); + } + hlist_del_init_rcu(&sc->service_list); + spin_unlock_bh(&sc->lock); + kfree_rcu(sc, rcu); +} + +void tipc_nametbl_stop(struct net *net) +{ + struct name_table *nt = tipc_name_table(net); + struct tipc_net *tn = tipc_net(net); + struct hlist_head *service_head; + struct tipc_service *service; + u32 i; + + /* Verify name table is empty and purge any lingering + * publications, then release the name table + */ + spin_lock_bh(&tn->nametbl_lock); + for (i = 0; i < TIPC_NAMETBL_SIZE; i++) { + if (hlist_empty(&nt->services[i])) + continue; + service_head = &nt->services[i]; + hlist_for_each_entry_rcu(service, service_head, service_list) { + tipc_service_delete(net, service); + } + } + spin_unlock_bh(&tn->nametbl_lock); + + synchronize_net(); + kfree(nt); +} + +static int __tipc_nl_add_nametable_publ(struct tipc_nl_msg *msg, + struct tipc_service *service, + struct service_range *sr, + u32 *last_key) +{ + struct publication *p; + struct nlattr *attrs; + struct nlattr *b; + void *hdr; + + if (*last_key) { + list_for_each_entry(p, &sr->all_publ, all_publ) + if (p->key == *last_key) + break; + if (list_entry_is_head(p, &sr->all_publ, all_publ)) + return -EPIPE; + } else { + p = list_first_entry(&sr->all_publ, + struct publication, + all_publ); + } + + list_for_each_entry_from(p, &sr->all_publ, all_publ) { + *last_key = p->key; + + hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, + &tipc_genl_family, NLM_F_MULTI, + TIPC_NL_NAME_TABLE_GET); + if (!hdr) + return -EMSGSIZE; + + attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_NAME_TABLE); + if (!attrs) + goto msg_full; + + b = nla_nest_start_noflag(msg->skb, TIPC_NLA_NAME_TABLE_PUBL); + if (!b) + goto attr_msg_full; + + if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_TYPE, service->type)) + goto publ_msg_full; + if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_LOWER, sr->lower)) + goto publ_msg_full; + if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_UPPER, sr->upper)) + goto publ_msg_full; + if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_SCOPE, p->scope)) + goto publ_msg_full; + if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_NODE, p->node)) + goto publ_msg_full; + if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_REF, p->port)) + goto publ_msg_full; + if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_KEY, p->key)) + goto publ_msg_full; + + nla_nest_end(msg->skb, b); + nla_nest_end(msg->skb, attrs); + genlmsg_end(msg->skb, hdr); + } + *last_key = 0; + + return 0; + +publ_msg_full: + nla_nest_cancel(msg->skb, b); +attr_msg_full: + nla_nest_cancel(msg->skb, attrs); +msg_full: + genlmsg_cancel(msg->skb, hdr); + + return -EMSGSIZE; +} + +static int __tipc_nl_service_range_list(struct tipc_nl_msg *msg, + struct tipc_service *sc, + u32 *last_lower, u32 *last_key) +{ + struct service_range *sr; + struct rb_node *n; + int err; + + for (n = rb_first(&sc->ranges); n; n = rb_next(n)) { + sr = container_of(n, struct service_range, tree_node); + if (sr->lower < *last_lower) + continue; + err = __tipc_nl_add_nametable_publ(msg, sc, sr, last_key); + if (err) { + *last_lower = sr->lower; + return err; + } + } + *last_lower = 0; + return 0; +} + +static int tipc_nl_service_list(struct net *net, struct tipc_nl_msg *msg, + u32 *last_type, u32 *last_lower, u32 *last_key) +{ + struct tipc_net *tn = tipc_net(net); + struct tipc_service *service = NULL; + struct hlist_head *head; + int err; + int i; + + if (*last_type) + i = hash(*last_type); + else + i = 0; + + for (; i < TIPC_NAMETBL_SIZE; i++) { + head = &tn->nametbl->services[i]; + + if (*last_type || + (!i && *last_key && (*last_lower == *last_key))) { + service = tipc_service_find(net, *last_type); + if (!service) + return -EPIPE; + } else { + hlist_for_each_entry_rcu(service, head, service_list) + break; + if (!service) + continue; + } + + hlist_for_each_entry_from_rcu(service, service_list) { + spin_lock_bh(&service->lock); + err = __tipc_nl_service_range_list(msg, service, + last_lower, + last_key); + + if (err) { + *last_type = service->type; + spin_unlock_bh(&service->lock); + return err; + } + spin_unlock_bh(&service->lock); + } + *last_type = 0; + } + return 0; +} + +int tipc_nl_name_table_dump(struct sk_buff *skb, struct netlink_callback *cb) +{ + struct net *net = sock_net(skb->sk); + u32 last_type = cb->args[0]; + u32 last_lower = cb->args[1]; + u32 last_key = cb->args[2]; + int done = cb->args[3]; + struct tipc_nl_msg msg; + int err; + + if (done) + return 0; + + msg.skb = skb; + msg.portid = NETLINK_CB(cb->skb).portid; + msg.seq = cb->nlh->nlmsg_seq; + + rcu_read_lock(); + err = tipc_nl_service_list(net, &msg, &last_type, + &last_lower, &last_key); + if (!err) { + done = 1; + } else if (err != -EMSGSIZE) { + /* We never set seq or call nl_dump_check_consistent() this + * means that setting prev_seq here will cause the consistence + * check to fail in the netlink callback handler. Resulting in + * the NLMSG_DONE message having the NLM_F_DUMP_INTR flag set if + * we got an error. + */ + cb->prev_seq = 1; + } + rcu_read_unlock(); + + cb->args[0] = last_type; + cb->args[1] = last_lower; + cb->args[2] = last_key; + cb->args[3] = done; + + return skb->len; +} + +struct tipc_dest *tipc_dest_find(struct list_head *l, u32 node, u32 port) +{ + struct tipc_dest *dst; + + list_for_each_entry(dst, l, list) { + if (dst->node == node && dst->port == port) + return dst; + } + return NULL; +} + +bool tipc_dest_push(struct list_head *l, u32 node, u32 port) +{ + struct tipc_dest *dst; + + if (tipc_dest_find(l, node, port)) + return false; + + dst = kmalloc(sizeof(*dst), GFP_ATOMIC); + if (unlikely(!dst)) + return false; + dst->node = node; + dst->port = port; + list_add(&dst->list, l); + return true; +} + +bool tipc_dest_pop(struct list_head *l, u32 *node, u32 *port) +{ + struct tipc_dest *dst; + + if (list_empty(l)) + return false; + dst = list_first_entry(l, typeof(*dst), list); + if (port) + *port = dst->port; + if (node) + *node = dst->node; + list_del(&dst->list); + kfree(dst); + return true; +} + +bool tipc_dest_del(struct list_head *l, u32 node, u32 port) +{ + struct tipc_dest *dst; + + dst = tipc_dest_find(l, node, port); + if (!dst) + return false; + list_del(&dst->list); + kfree(dst); + return true; +} + +void tipc_dest_list_purge(struct list_head *l) +{ + struct tipc_dest *dst, *tmp; + + list_for_each_entry_safe(dst, tmp, l, list) { + list_del(&dst->list); + kfree(dst); + } +} + +int tipc_dest_list_len(struct list_head *l) +{ + struct tipc_dest *dst; + int i = 0; + + list_for_each_entry(dst, l, list) { + i++; + } + return i; +} |