diff options
Diffstat (limited to 'net/tipc/bearer.c')
| -rw-r--r-- | net/tipc/bearer.c | 629 |
1 files changed, 629 insertions, 0 deletions
diff --git a/net/tipc/bearer.c b/net/tipc/bearer.c new file mode 100644 index 00000000..5dfd89c4 --- /dev/null +++ b/net/tipc/bearer.c @@ -0,0 +1,629 @@ +/* + * net/tipc/bearer.c: TIPC bearer code + * + * Copyright (c) 1996-2006, Ericsson AB + * Copyright (c) 2004-2006, 2010-2011, 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 "core.h" +#include "config.h" +#include "bearer.h" +#include "discover.h" + +#define MAX_ADDR_STR 32 + +static struct tipc_media *media_list[MAX_MEDIA]; +static u32 media_count; + +struct tipc_bearer tipc_bearers[MAX_BEARERS]; + +static void bearer_disable(struct tipc_bearer *b_ptr); + +/** + * media_name_valid - validate media name + * + * Returns 1 if media name is valid, otherwise 0. + */ + +static int media_name_valid(const char *name) +{ + u32 len; + + len = strlen(name); + if ((len + 1) > TIPC_MAX_MEDIA_NAME) + return 0; + return strspn(name, tipc_alphabet) == len; +} + +/** + * tipc_media_find - locates specified media object by name + */ + +struct tipc_media *tipc_media_find(const char *name) +{ + u32 i; + + for (i = 0; i < media_count; i++) { + if (!strcmp(media_list[i]->name, name)) + return media_list[i]; + } + return NULL; +} + +/** + * media_find_id - locates specified media object by type identifier + */ + +static struct tipc_media *media_find_id(u8 type) +{ + u32 i; + + for (i = 0; i < media_count; i++) { + if (media_list[i]->type_id == type) + return media_list[i]; + } + return NULL; +} + +/** + * tipc_register_media - register a media type + * + * Bearers for this media type must be activated separately at a later stage. + */ + +int tipc_register_media(struct tipc_media *m_ptr) +{ + int res = -EINVAL; + + write_lock_bh(&tipc_net_lock); + + if (!media_name_valid(m_ptr->name)) + goto exit; + if ((m_ptr->bcast_addr.media_id != m_ptr->type_id) || + !m_ptr->bcast_addr.broadcast) + goto exit; + if (m_ptr->priority > TIPC_MAX_LINK_PRI) + goto exit; + if ((m_ptr->tolerance < TIPC_MIN_LINK_TOL) || + (m_ptr->tolerance > TIPC_MAX_LINK_TOL)) + goto exit; + if (media_count >= MAX_MEDIA) + goto exit; + if (tipc_media_find(m_ptr->name) || media_find_id(m_ptr->type_id)) + goto exit; + + media_list[media_count] = m_ptr; + media_count++; + res = 0; +exit: + write_unlock_bh(&tipc_net_lock); + if (res) + warn("Media <%s> registration error\n", m_ptr->name); + return res; +} + +/** + * tipc_media_addr_printf - record media address in print buffer + */ + +void tipc_media_addr_printf(struct print_buf *pb, struct tipc_media_addr *a) +{ + char addr_str[MAX_ADDR_STR]; + struct tipc_media *m_ptr; + + m_ptr = media_find_id(a->media_id); + + if (m_ptr && !m_ptr->addr2str(a, addr_str, sizeof(addr_str))) + tipc_printf(pb, "%s(%s)", m_ptr->name, addr_str); + else { + u32 i; + + tipc_printf(pb, "UNKNOWN(%u)", a->media_id); + for (i = 0; i < sizeof(a->value); i++) + tipc_printf(pb, "-%02x", a->value[i]); + } +} + +/** + * tipc_media_get_names - record names of registered media in buffer + */ + +struct sk_buff *tipc_media_get_names(void) +{ + struct sk_buff *buf; + int i; + + buf = tipc_cfg_reply_alloc(MAX_MEDIA * TLV_SPACE(TIPC_MAX_MEDIA_NAME)); + if (!buf) + return NULL; + + read_lock_bh(&tipc_net_lock); + for (i = 0; i < media_count; i++) { + tipc_cfg_append_tlv(buf, TIPC_TLV_MEDIA_NAME, + media_list[i]->name, + strlen(media_list[i]->name) + 1); + } + read_unlock_bh(&tipc_net_lock); + return buf; +} + +/** + * bearer_name_validate - validate & (optionally) deconstruct bearer name + * @name - ptr to bearer name string + * @name_parts - ptr to area for bearer name components (or NULL if not needed) + * + * Returns 1 if bearer name is valid, otherwise 0. + */ + +static int bearer_name_validate(const char *name, + struct tipc_bearer_names *name_parts) +{ + char name_copy[TIPC_MAX_BEARER_NAME]; + char *media_name; + char *if_name; + u32 media_len; + u32 if_len; + + /* copy bearer name & ensure length is OK */ + + name_copy[TIPC_MAX_BEARER_NAME - 1] = 0; + /* need above in case non-Posix strncpy() doesn't pad with nulls */ + strncpy(name_copy, name, TIPC_MAX_BEARER_NAME); + if (name_copy[TIPC_MAX_BEARER_NAME - 1] != 0) + return 0; + + /* ensure all component parts of bearer name are present */ + + media_name = name_copy; + if_name = strchr(media_name, ':'); + if (if_name == NULL) + return 0; + *(if_name++) = 0; + media_len = if_name - media_name; + if_len = strlen(if_name) + 1; + + /* validate component parts of bearer name */ + + if ((media_len <= 1) || (media_len > TIPC_MAX_MEDIA_NAME) || + (if_len <= 1) || (if_len > TIPC_MAX_IF_NAME) || + (strspn(media_name, tipc_alphabet) != (media_len - 1)) || + (strspn(if_name, tipc_alphabet) != (if_len - 1))) + return 0; + + /* return bearer name components, if necessary */ + + if (name_parts) { + strcpy(name_parts->media_name, media_name); + strcpy(name_parts->if_name, if_name); + } + return 1; +} + +/** + * tipc_bearer_find - locates bearer object with matching bearer name + */ + +struct tipc_bearer *tipc_bearer_find(const char *name) +{ + struct tipc_bearer *b_ptr; + u32 i; + + for (i = 0, b_ptr = tipc_bearers; i < MAX_BEARERS; i++, b_ptr++) { + if (b_ptr->active && (!strcmp(b_ptr->name, name))) + return b_ptr; + } + return NULL; +} + +/** + * tipc_bearer_find_interface - locates bearer object with matching interface name + */ + +struct tipc_bearer *tipc_bearer_find_interface(const char *if_name) +{ + struct tipc_bearer *b_ptr; + char *b_if_name; + u32 i; + + for (i = 0, b_ptr = tipc_bearers; i < MAX_BEARERS; i++, b_ptr++) { + if (!b_ptr->active) + continue; + b_if_name = strchr(b_ptr->name, ':') + 1; + if (!strcmp(b_if_name, if_name)) + return b_ptr; + } + return NULL; +} + +/** + * tipc_bearer_get_names - record names of bearers in buffer + */ + +struct sk_buff *tipc_bearer_get_names(void) +{ + struct sk_buff *buf; + struct tipc_bearer *b_ptr; + int i, j; + + buf = tipc_cfg_reply_alloc(MAX_BEARERS * TLV_SPACE(TIPC_MAX_BEARER_NAME)); + if (!buf) + return NULL; + + read_lock_bh(&tipc_net_lock); + for (i = 0; i < media_count; i++) { + for (j = 0; j < MAX_BEARERS; j++) { + b_ptr = &tipc_bearers[j]; + if (b_ptr->active && (b_ptr->media == media_list[i])) { + tipc_cfg_append_tlv(buf, TIPC_TLV_BEARER_NAME, + b_ptr->name, + strlen(b_ptr->name) + 1); + } + } + } + read_unlock_bh(&tipc_net_lock); + return buf; +} + +void tipc_bearer_add_dest(struct tipc_bearer *b_ptr, u32 dest) +{ + tipc_nmap_add(&b_ptr->nodes, dest); + tipc_bcbearer_sort(); + tipc_disc_add_dest(b_ptr->link_req); +} + +void tipc_bearer_remove_dest(struct tipc_bearer *b_ptr, u32 dest) +{ + tipc_nmap_remove(&b_ptr->nodes, dest); + tipc_bcbearer_sort(); + tipc_disc_remove_dest(b_ptr->link_req); +} + +/* + * bearer_push(): Resolve bearer congestion. Force the waiting + * links to push out their unsent packets, one packet per link + * per iteration, until all packets are gone or congestion reoccurs. + * 'tipc_net_lock' is read_locked when this function is called + * bearer.lock must be taken before calling + * Returns binary true(1) ore false(0) + */ +static int bearer_push(struct tipc_bearer *b_ptr) +{ + u32 res = 0; + struct tipc_link *ln, *tln; + + if (b_ptr->blocked) + return 0; + + while (!list_empty(&b_ptr->cong_links) && (res != PUSH_FAILED)) { + list_for_each_entry_safe(ln, tln, &b_ptr->cong_links, link_list) { + res = tipc_link_push_packet(ln); + if (res == PUSH_FAILED) + break; + if (res == PUSH_FINISHED) + list_move_tail(&ln->link_list, &b_ptr->links); + } + } + return list_empty(&b_ptr->cong_links); +} + +void tipc_bearer_lock_push(struct tipc_bearer *b_ptr) +{ + spin_lock_bh(&b_ptr->lock); + bearer_push(b_ptr); + spin_unlock_bh(&b_ptr->lock); +} + + +/* + * Interrupt enabling new requests after bearer congestion or blocking: + * See bearer_send(). + */ +void tipc_continue(struct tipc_bearer *b_ptr) +{ + spin_lock_bh(&b_ptr->lock); + if (!list_empty(&b_ptr->cong_links)) + tipc_k_signal((Handler)tipc_bearer_lock_push, (unsigned long)b_ptr); + b_ptr->blocked = 0; + spin_unlock_bh(&b_ptr->lock); +} + +/* + * Schedule link for sending of messages after the bearer + * has been deblocked by 'continue()'. This method is called + * when somebody tries to send a message via this link while + * the bearer is congested. 'tipc_net_lock' is in read_lock here + * bearer.lock is busy + */ + +static void tipc_bearer_schedule_unlocked(struct tipc_bearer *b_ptr, + struct tipc_link *l_ptr) +{ + list_move_tail(&l_ptr->link_list, &b_ptr->cong_links); +} + +/* + * Schedule link for sending of messages after the bearer + * has been deblocked by 'continue()'. This method is called + * when somebody tries to send a message via this link while + * the bearer is congested. 'tipc_net_lock' is in read_lock here, + * bearer.lock is free + */ + +void tipc_bearer_schedule(struct tipc_bearer *b_ptr, struct tipc_link *l_ptr) +{ + spin_lock_bh(&b_ptr->lock); + tipc_bearer_schedule_unlocked(b_ptr, l_ptr); + spin_unlock_bh(&b_ptr->lock); +} + + +/* + * tipc_bearer_resolve_congestion(): Check if there is bearer congestion, + * and if there is, try to resolve it before returning. + * 'tipc_net_lock' is read_locked when this function is called + */ +int tipc_bearer_resolve_congestion(struct tipc_bearer *b_ptr, + struct tipc_link *l_ptr) +{ + int res = 1; + + if (list_empty(&b_ptr->cong_links)) + return 1; + spin_lock_bh(&b_ptr->lock); + if (!bearer_push(b_ptr)) { + tipc_bearer_schedule_unlocked(b_ptr, l_ptr); + res = 0; + } + spin_unlock_bh(&b_ptr->lock); + return res; +} + +/** + * tipc_bearer_congested - determines if bearer is currently congested + */ + +int tipc_bearer_congested(struct tipc_bearer *b_ptr, struct tipc_link *l_ptr) +{ + if (unlikely(b_ptr->blocked)) + return 1; + if (likely(list_empty(&b_ptr->cong_links))) + return 0; + return !tipc_bearer_resolve_congestion(b_ptr, l_ptr); +} + +/** + * tipc_enable_bearer - enable bearer with the given name + */ + +int tipc_enable_bearer(const char *name, u32 disc_domain, u32 priority) +{ + struct tipc_bearer *b_ptr; + struct tipc_media *m_ptr; + struct tipc_bearer_names b_names; + char addr_string[16]; + u32 bearer_id; + u32 with_this_prio; + u32 i; + int res = -EINVAL; + + if (!tipc_own_addr) { + warn("Bearer <%s> rejected, not supported in standalone mode\n", + name); + return -ENOPROTOOPT; + } + if (!bearer_name_validate(name, &b_names)) { + warn("Bearer <%s> rejected, illegal name\n", name); + return -EINVAL; + } + if (tipc_addr_domain_valid(disc_domain) && + (disc_domain != tipc_own_addr)) { + if (tipc_in_scope(disc_domain, tipc_own_addr)) { + disc_domain = tipc_own_addr & TIPC_CLUSTER_MASK; + res = 0; /* accept any node in own cluster */ + } else if (in_own_cluster(disc_domain)) + res = 0; /* accept specified node in own cluster */ + } + if (res) { + warn("Bearer <%s> rejected, illegal discovery domain\n", name); + return -EINVAL; + } + if ((priority > TIPC_MAX_LINK_PRI) && + (priority != TIPC_MEDIA_LINK_PRI)) { + warn("Bearer <%s> rejected, illegal priority\n", name); + return -EINVAL; + } + + write_lock_bh(&tipc_net_lock); + + m_ptr = tipc_media_find(b_names.media_name); + if (!m_ptr) { + warn("Bearer <%s> rejected, media <%s> not registered\n", name, + b_names.media_name); + goto exit; + } + + if (priority == TIPC_MEDIA_LINK_PRI) + priority = m_ptr->priority; + +restart: + bearer_id = MAX_BEARERS; + with_this_prio = 1; + for (i = MAX_BEARERS; i-- != 0; ) { + if (!tipc_bearers[i].active) { + bearer_id = i; + continue; + } + if (!strcmp(name, tipc_bearers[i].name)) { + warn("Bearer <%s> rejected, already enabled\n", name); + goto exit; + } + if ((tipc_bearers[i].priority == priority) && + (++with_this_prio > 2)) { + if (priority-- == 0) { + warn("Bearer <%s> rejected, duplicate priority\n", + name); + goto exit; + } + warn("Bearer <%s> priority adjustment required %u->%u\n", + name, priority + 1, priority); + goto restart; + } + } + if (bearer_id >= MAX_BEARERS) { + warn("Bearer <%s> rejected, bearer limit reached (%u)\n", + name, MAX_BEARERS); + goto exit; + } + + b_ptr = &tipc_bearers[bearer_id]; + strcpy(b_ptr->name, name); + res = m_ptr->enable_bearer(b_ptr); + if (res) { + warn("Bearer <%s> rejected, enable failure (%d)\n", name, -res); + goto exit; + } + + b_ptr->identity = bearer_id; + b_ptr->media = m_ptr; + b_ptr->tolerance = m_ptr->tolerance; + b_ptr->window = m_ptr->window; + b_ptr->net_plane = bearer_id + 'A'; + b_ptr->active = 1; + b_ptr->priority = priority; + INIT_LIST_HEAD(&b_ptr->cong_links); + INIT_LIST_HEAD(&b_ptr->links); + spin_lock_init(&b_ptr->lock); + + res = tipc_disc_create(b_ptr, &m_ptr->bcast_addr, disc_domain); + if (res) { + bearer_disable(b_ptr); + warn("Bearer <%s> rejected, discovery object creation failed\n", + name); + goto exit; + } + info("Enabled bearer <%s>, discovery domain %s, priority %u\n", + name, tipc_addr_string_fill(addr_string, disc_domain), priority); +exit: + write_unlock_bh(&tipc_net_lock); + return res; +} + +/** + * tipc_block_bearer(): Block the bearer with the given name, + * and reset all its links + */ + +int tipc_block_bearer(const char *name) +{ + struct tipc_bearer *b_ptr = NULL; + struct tipc_link *l_ptr; + struct tipc_link *temp_l_ptr; + + read_lock_bh(&tipc_net_lock); + b_ptr = tipc_bearer_find(name); + if (!b_ptr) { + warn("Attempt to block unknown bearer <%s>\n", name); + read_unlock_bh(&tipc_net_lock); + return -EINVAL; + } + + info("Blocking bearer <%s>\n", name); + spin_lock_bh(&b_ptr->lock); + b_ptr->blocked = 1; + list_splice_init(&b_ptr->cong_links, &b_ptr->links); + list_for_each_entry_safe(l_ptr, temp_l_ptr, &b_ptr->links, link_list) { + struct tipc_node *n_ptr = l_ptr->owner; + + spin_lock_bh(&n_ptr->lock); + tipc_link_reset(l_ptr); + spin_unlock_bh(&n_ptr->lock); + } + spin_unlock_bh(&b_ptr->lock); + read_unlock_bh(&tipc_net_lock); + return 0; +} + +/** + * bearer_disable - + * + * Note: This routine assumes caller holds tipc_net_lock. + */ + +static void bearer_disable(struct tipc_bearer *b_ptr) +{ + struct tipc_link *l_ptr; + struct tipc_link *temp_l_ptr; + + info("Disabling bearer <%s>\n", b_ptr->name); + spin_lock_bh(&b_ptr->lock); + b_ptr->blocked = 1; + b_ptr->media->disable_bearer(b_ptr); + list_splice_init(&b_ptr->cong_links, &b_ptr->links); + list_for_each_entry_safe(l_ptr, temp_l_ptr, &b_ptr->links, link_list) { + tipc_link_delete(l_ptr); + } + if (b_ptr->link_req) + tipc_disc_delete(b_ptr->link_req); + spin_unlock_bh(&b_ptr->lock); + memset(b_ptr, 0, sizeof(struct tipc_bearer)); +} + +int tipc_disable_bearer(const char *name) +{ + struct tipc_bearer *b_ptr; + int res; + + write_lock_bh(&tipc_net_lock); + b_ptr = tipc_bearer_find(name); + if (b_ptr == NULL) { + warn("Attempt to disable unknown bearer <%s>\n", name); + res = -EINVAL; + } else { + bearer_disable(b_ptr); + res = 0; + } + write_unlock_bh(&tipc_net_lock); + return res; +} + + + +void tipc_bearer_stop(void) +{ + u32 i; + + for (i = 0; i < MAX_BEARERS; i++) { + if (tipc_bearers[i].active) + bearer_disable(&tipc_bearers[i]); + } + media_count = 0; +} |