// SPDX-License-Identifier: GPL-2.0-or-later/* RxRPC remote transport endpoint record management * * Copyright (C) 2007, 2016 Red Hat, Inc. All Rights Reserved. * Written by David Howells (dhowells@redhat.com) */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/module.h>#include <linux/net.h>#include <linux/skbuff.h>#include <linux/udp.h>#include <linux/in.h>#include <linux/in6.h>#include <linux/slab.h>#include <linux/hashtable.h>#include <net/sock.h>#include <net/af_rxrpc.h>#include <net/ip.h>#include <net/route.h>#include <net/ip6_route.h>#include "ar-internal.h" static const struct sockaddr_rxrpc rxrpc_null_addr; /* * Hash a peer key. */static unsigned long rxrpc_peer_hash_key(struct rxrpc_local *local, const struct sockaddr_rxrpc *srx){ const u16 *p; unsigned int i, size; unsigned long hash_key; _enter(""); hash_key = (unsigned long)local / __alignof__(*local); hash_key += srx->transport_type; hash_key += srx->transport_len; hash_key += srx->transport.family; switch (srx->transport.family) { case AF_INET: hash_key += (u16 __force)srx->transport.sin.sin_port; size = sizeof(srx->transport.sin.sin_addr); p = (u16 *)&srx->transport.sin.sin_addr; break;#ifdef CONFIG_AF_RXRPC_IPV6 case AF_INET6: hash_key += (u16 __force)srx->transport.sin.sin_port; size = sizeof(srx->transport.sin6.sin6_addr); p = (u16 *)&srx->transport.sin6.sin6_addr; break;#endif default: WARN(1, "AF_RXRPC: Unsupported transport address family\n"); return 0; } /* Step through the peer address in 16-bit portions for speed */ for (i = 0; i < size; i += sizeof(*p), p++) hash_key += *p; _leave(" 0x%lx", hash_key); return hash_key;} /* * Compare a peer to a key. Return -ve, 0 or +ve to indicate less than, same * or greater than. * * Unfortunately, the primitives in linux/hashtable.h don't allow for sorted * buckets and mid-bucket insertion, so we don't make full use of this * information at this point. */static long rxrpc_peer_cmp_key(const struct rxrpc_peer *peer, struct rxrpc_local *local, const struct sockaddr_rxrpc *srx, unsigned long hash_key){ long diff; diff = ((peer->hash_key - hash_key) ?: ((unsigned long)peer->local - (unsigned long)local) ?: (peer->srx.transport_type - srx->transport_type) ?: (peer->srx.transport_len - srx->transport_len) ?: (peer->srx.transport.family - srx->transport.family)); if (diff != 0) return diff; switch (srx->transport.family) { case AF_INET: return ((u16 __force)peer->srx.transport.sin.sin_port - (u16 __force)srx->transport.sin.sin_port) ?: memcmp(&peer->srx.transport.sin.sin_addr, &srx->transport.sin.sin_addr, sizeof(struct in_addr));#ifdef CONFIG_AF_RXRPC_IPV6 case AF_INET6: return ((u16 __force)peer->srx.transport.sin6.sin6_port - (u16 __force)srx->transport.sin6.sin6_port) ?: memcmp(&peer->srx.transport.sin6.sin6_addr, &srx->transport.sin6.sin6_addr, sizeof(struct in6_addr));#endif default: BUG(); }} /* * Look up a remote transport endpoint for the specified address using RCU. */static struct rxrpc_peer *__rxrpc_lookup_peer_rcu( struct rxrpc_local *local, const struct sockaddr_rxrpc *srx, unsigned long hash_key){ struct rxrpc_peer *peer; struct rxrpc_net *rxnet = local->rxnet; hash_for_each_possible_rcu(rxnet->peer_hash, peer, hash_link, hash_key) { if (rxrpc_peer_cmp_key(peer, local, srx, hash_key) == 0 && refcount_read(&peer->ref) > 0) return peer; } return NULL;} /* * Look up a remote transport endpoint for the specified address using RCU. */struct rxrpc_peer *rxrpc_lookup_peer_rcu(struct rxrpc_local *local, const struct sockaddr_rxrpc *srx){ struct rxrpc_peer *peer; unsigned long hash_key = rxrpc_peer_hash_key(local, srx); peer = __rxrpc_lookup_peer_rcu(local, srx, hash_key); if (peer) _leave(" = %p {u=%d}", peer, refcount_read(&peer->ref)); return peer;} /* * assess the MTU size for the network interface through which this peer is * reached */void rxrpc_assess_MTU_size(struct rxrpc_local *local, struct rxrpc_peer *peer){ struct net *net = local->net; struct dst_entry *dst; struct rtable *rt; struct flowi fl; struct flowi4 *fl4 = &fl.u.ip4;#ifdef CONFIG_AF_RXRPC_IPV6 struct flowi6 *fl6 = &fl.u.ip6;#endif peer->if_mtu = 1500; if (peer->max_data < peer->if_mtu - peer->hdrsize) { trace_rxrpc_pmtud_reduce(peer, 0, peer->if_mtu - peer->hdrsize, rxrpc_pmtud_reduce_route); peer->max_data = peer->if_mtu - peer->hdrsize; } memset(&fl, 0, sizeof(fl)); switch (peer->srx.transport.family) { case AF_INET: rt = ip_route_output_ports( net, fl4, NULL, peer->srx.transport.sin.sin_addr.s_addr, 0, htons(7000), htons(7001), IPPROTO_UDP, 0, 0); if (IS_ERR(rt)) { _leave(" [route err %ld]", PTR_ERR(rt)); return; } dst = &rt->dst; break; #ifdef CONFIG_AF_RXRPC_IPV6 case AF_INET6: fl6->flowi6_iif = LOOPBACK_IFINDEX; fl6->flowi6_scope = RT_SCOPE_UNIVERSE; fl6->flowi6_proto = IPPROTO_UDP; memcpy(&fl6->daddr, &peer->srx.transport.sin6.sin6_addr, sizeof(struct in6_addr)); fl6->fl6_dport = htons(7001); fl6->fl6_sport = htons(7000); dst = ip6_route_output(net, NULL, fl6); if (dst->error) { _leave(" [route err %d]", dst->error); return; } break;#endif default: BUG(); } peer->if_mtu = dst_mtu(dst); peer->hdrsize += dst->header_len + dst->trailer_len; peer->tx_seg_max = dst->dev->gso_max_segs; dst_release(dst); peer->max_data = umin(RXRPC_JUMBO(1), peer->if_mtu - peer->hdrsize); peer->pmtud_good = 500; peer->pmtud_bad = peer->if_mtu - peer->hdrsize + 1; peer->pmtud_trial = umin(peer->max_data, peer->pmtud_bad - 1); peer->pmtud_pending = true; _leave(" [if_mtu %u]", peer->if_mtu);} /* * Allocate a peer. */struct rxrpc_peer *rxrpc_alloc_peer(struct rxrpc_local *local, gfp_t gfp, enum rxrpc_peer_trace why){ struct rxrpc_peer *peer; _enter(""); peer = kzalloc_obj(struct rxrpc_peer, gfp); if (peer) { refcount_set(&peer->ref, 1); peer->local = rxrpc_get_local(local, rxrpc_local_get_peer); INIT_HLIST_HEAD(&peer->error_targets); peer->service_conns = RB_ROOT; seqlock_init(&peer->service_conn_lock); spin_lock_init(&peer->lock); peer->debug_id = atomic_inc_return(&rxrpc_debug_id); peer->recent_srtt_us = UINT_MAX; peer->cong_ssthresh = RXRPC_TX_MAX_WINDOW; trace_rxrpc_peer(peer->debug_id, 1, why); } _leave(" = %p", peer); return peer;} /* * Initialise peer record. */static void rxrpc_init_peer(struct rxrpc_local *local, struct rxrpc_peer *peer, unsigned long hash_key){ peer->hash_key = hash_key; switch (peer->srx.transport.family) { case AF_INET: peer->hdrsize = sizeof(struct iphdr); break;#ifdef CONFIG_AF_RXRPC_IPV6 case AF_INET6: peer->hdrsize = sizeof(struct ipv6hdr); break;#endif default: BUG(); } switch (peer->srx.transport_type) { case SOCK_DGRAM: peer->hdrsize += sizeof(struct udphdr); break; default: BUG(); } peer->hdrsize += sizeof(struct rxrpc_wire_header); peer->max_data = peer->if_mtu - peer->hdrsize;} /* * Set up a new peer. */static struct rxrpc_peer *rxrpc_create_peer(struct rxrpc_local *local, struct sockaddr_rxrpc *srx, unsigned long hash_key, gfp_t gfp){ struct rxrpc_peer *peer; _enter(""); peer = rxrpc_alloc_peer(local, gfp, rxrpc_peer_new_client); if (peer) { memcpy(&peer->srx, srx, sizeof(*srx)); rxrpc_init_peer(local, peer, hash_key); rxrpc_assess_MTU_size(local, peer); } _leave(" = %p", peer); return peer;} static void rxrpc_free_peer(struct rxrpc_peer *peer){ trace_rxrpc_peer(peer->debug_id, 0, rxrpc_peer_free); rxrpc_put_local(peer->local, rxrpc_local_put_peer); kfree_rcu(peer, rcu);} /* * Set up a new incoming peer. There shouldn't be any other matching peers * since we've already done a search in the list from the non-reentrant context * (the data_ready handler) that is the only place we can add new peers. * Called with interrupts disabled. */void rxrpc_new_incoming_peer(struct rxrpc_local *local, struct rxrpc_peer *peer){ struct rxrpc_net *rxnet = local->rxnet; unsigned long hash_key; hash_key = rxrpc_peer_hash_key(local, &peer->srx); rxrpc_init_peer(local, peer, hash_key); spin_lock(&rxnet->peer_hash_lock); hash_add_rcu(rxnet->peer_hash, &peer->hash_link, hash_key); list_add_tail(&peer->keepalive_link, &rxnet->peer_keepalive_new); spin_unlock(&rxnet->peer_hash_lock);} /* * obtain a remote transport endpoint for the specified address */struct rxrpc_peer *rxrpc_lookup_peer(struct rxrpc_local *local, struct sockaddr_rxrpc *srx, gfp_t gfp){ struct rxrpc_peer *peer, *candidate; struct rxrpc_net *rxnet = local->rxnet; unsigned long hash_key = rxrpc_peer_hash_key(local, srx); _enter("{%pISp}", &srx->transport); /* search the peer list first */ rcu_read_lock(); peer = __rxrpc_lookup_peer_rcu(local, srx, hash_key); if (peer && !rxrpc_get_peer_maybe(peer, rxrpc_peer_get_lookup_client)) peer = NULL; rcu_read_unlock(); if (!peer) { /* The peer is not yet present in hash - create a candidate * for a new record and then redo the search. */ candidate = rxrpc_create_peer(local, srx, hash_key, gfp); if (!candidate) { _leave(" = NULL [nomem]"); return NULL; } spin_lock_bh(&rxnet->peer_hash_lock); /* Need to check that we aren't racing with someone else */ peer = __rxrpc_lookup_peer_rcu(local, srx, hash_key); if (peer && !rxrpc_get_peer_maybe(peer, rxrpc_peer_get_lookup_client)) peer = NULL; if (!peer) { hash_add_rcu(rxnet->peer_hash, &candidate->hash_link, hash_key); list_add_tail(&candidate->keepalive_link, &rxnet->peer_keepalive_new); } spin_unlock_bh(&rxnet->peer_hash_lock); if (peer) rxrpc_free_peer(candidate); else peer = candidate; } _leave(" = %p {u=%d}", peer, refcount_read(&peer->ref)); return peer;} /* * Get a ref on a peer record. */struct rxrpc_peer *rxrpc_get_peer(struct rxrpc_peer *peer, enum rxrpc_peer_trace why){ int r; __refcount_inc(&peer->ref, &r); trace_rxrpc_peer(peer->debug_id, r + 1, why); return peer;} /* * Get a ref on a peer record unless its usage has already reached 0. */struct rxrpc_peer *rxrpc_get_peer_maybe(struct rxrpc_peer *peer, enum rxrpc_peer_trace why){ int r; if (peer) { if (__refcount_inc_not_zero(&peer->ref, &r)) trace_rxrpc_peer(peer->debug_id, r + 1, why); else peer = NULL; } return peer;} /* * Discard a peer record. */static void __rxrpc_put_peer(struct rxrpc_peer *peer){ struct rxrpc_net *rxnet = peer->local->rxnet; ASSERT(hlist_empty(&peer->error_targets)); spin_lock_bh(&rxnet->peer_hash_lock); hash_del_rcu(&peer->hash_link); list_del_init(&peer->keepalive_link); spin_unlock_bh(&rxnet->peer_hash_lock); rxrpc_free_peer(peer);} /* * Drop a ref on a peer record. */void rxrpc_put_peer(struct rxrpc_peer *peer, enum rxrpc_peer_trace why){ unsigned int debug_id; bool dead; int r; if (peer) { debug_id = peer->debug_id; dead = __refcount_dec_and_test(&peer->ref, &r); trace_rxrpc_peer(debug_id, r - 1, why); if (dead) __rxrpc_put_peer(peer); }} /* * Make sure all peer records have been discarded. */void rxrpc_destroy_all_peers(struct rxrpc_net *rxnet){ struct rxrpc_peer *peer; int i; for (i = 0; i < HASH_SIZE(rxnet->peer_hash); i++) { if (hlist_empty(&rxnet->peer_hash[i])) continue; hlist_for_each_entry(peer, &rxnet->peer_hash[i], hash_link) { pr_err("Leaked peer %x {%u} %pISp\n", peer->debug_id, refcount_read(&peer->ref), &peer->srx.transport); } }} /** * rxrpc_kernel_get_call_peer - Get the peer address of a call * @sock: The socket on which the call is in progress. * @call: The call to query * * Get a record for the remote peer in a call. * * Return: The call's peer record. */struct rxrpc_peer *rxrpc_kernel_get_call_peer(struct socket *sock, struct rxrpc_call *call){ return rxrpc_get_peer(call->peer, rxrpc_peer_get_application);}EXPORT_SYMBOL(rxrpc_kernel_get_call_peer); /** * rxrpc_kernel_get_srtt - Get a call's peer smoothed RTT * @peer: The peer to query * * Get the call's peer smoothed RTT. * * Return: The RTT in uS or %UINT_MAX if we have no samples. */unsigned int rxrpc_kernel_get_srtt(const struct rxrpc_peer *peer){ return READ_ONCE(peer->recent_srtt_us);}EXPORT_SYMBOL(rxrpc_kernel_get_srtt); /** * rxrpc_kernel_remote_srx - Get the address of a peerLines 1–500 of 560. 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// SPDX-License-Identifier: GPL-2.0-or-later /* RxRPC remote transport endpoint record management * * Copyright (C) 2007, 2016 Red Hat, Inc. All Rights Reserved. * Written by David Howells (dhowells@redhat.com) */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/module.h> #include <linux/net.h> #include <linux/skbuff.h> #include <linux/udp.h> #include <linux/in.h> #include <linux/in6.h> #include <linux/slab.h> #include <linux/hashtable.h> #include <net/sock.h> #include <net/af_rxrpc.h> #include <net/ip.h> #include <net/route.h> #include <net/ip6_route.h> #include "ar-internal.h" static const struct sockaddr_rxrpc rxrpc_null_addr; /* * Hash a peer key. */ static unsigned long rxrpc_peer_hash_key(struct rxrpc_local *local, const struct sockaddr_rxrpc *srx) { const u16 *p; unsigned int i, size; unsigned long hash_key; _enter(""); hash_key = (unsigned long)local / __alignof__(*local); hash_key += srx->transport_type; hash_key += srx->transport_len; hash_key += srx->transport.family; switch (srx->transport.family) { case AF_INET: hash_key += (u16 __force)srx->transport.sin.sin_port; size = sizeof(srx->transport.sin.sin_addr); p = (u16 *)&srx->transport.sin.sin_addr; break; #ifdef CONFIG_AF_RXRPC_IPV6 case AF_INET6: hash_key += (u16 __force)srx->transport.sin.sin_port; size = sizeof(srx->transport.sin6.sin6_addr); p = (u16 *)&srx->transport.sin6.sin6_addr; break; #endif default: WARN(1, "AF_RXRPC: Unsupported transport address family\n"); return 0; } /* Step through the peer address in 16-bit portions for speed */ for (i = 0; i < size; i += sizeof(*p), p++) hash_key += *p; _leave(" 0x%lx", hash_key); return hash_key; } /* * Compare a peer to a key. Return -ve, 0 or +ve to indicate less than, same * or greater than. * * Unfortunately, the primitives in linux/hashtable.h don't allow for sorted * buckets and mid-bucket insertion, so we don't make full use of this * information at this point. */ static long rxrpc_peer_cmp_key(const struct rxrpc_peer *peer, struct rxrpc_local *local, const struct sockaddr_rxrpc *srx, unsigned long hash_key) { long diff; diff = ((peer->hash_key - hash_key) ?: ((unsigned long)peer->local - (unsigned long)local) ?: (peer->srx.transport_type - srx->transport_type) ?: (peer->srx.transport_len - srx->transport_len) ?: (peer->srx.transport.family - srx->transport.family)); if (diff != 0) return diff; switch (srx->transport.family) { case AF_INET: return ((u16 __force)peer->srx.transport.sin.sin_port - (u16 __force)srx->transport.sin.sin_port) ?: memcmp(&peer->srx.transport.sin.sin_addr, &srx->transport.sin.sin_addr, sizeof(struct in_addr)); #ifdef CONFIG_AF_RXRPC_IPV6 case AF_INET6: return ((u16 __force)peer->srx.transport.sin6.sin6_port - (u16 __force)srx->transport.sin6.sin6_port) ?: memcmp(&peer->srx.transport.sin6.sin6_addr, &srx->transport.sin6.sin6_addr, sizeof(struct in6_addr)); #endif default: BUG(); } } /* * Look up a remote transport endpoint for the specified address using RCU. */ static struct rxrpc_peer *__rxrpc_lookup_peer_rcu( struct rxrpc_local *local, const struct sockaddr_rxrpc *srx, unsigned long hash_key) { struct rxrpc_peer *peer; struct rxrpc_net *rxnet = local->rxnet; hash_for_each_possible_rcu(rxnet->peer_hash, peer, hash_link, hash_key) { if (rxrpc_peer_cmp_key(peer, local, srx, hash_key) == 0 && refcount_read(&peer->ref) > 0) return peer; } return NULL; } /* * Look up a remote transport endpoint for the specified address using RCU. */ struct rxrpc_peer *rxrpc_lookup_peer_rcu(struct rxrpc_local *local, const struct sockaddr_rxrpc *srx) { struct rxrpc_peer *peer; unsigned long hash_key = rxrpc_peer_hash_key(local, srx); peer = __rxrpc_lookup_peer_rcu(local, srx, hash_key); if (peer) _leave(" = %p {u=%d}", peer, refcount_read(&peer->ref)); return peer; } /* * assess the MTU size for the network interface through which this peer is * reached */ void rxrpc_assess_MTU_size(struct rxrpc_local *local, struct rxrpc_peer *peer) { struct net *net = local->net; struct dst_entry *dst; struct rtable *rt; struct flowi fl; struct flowi4 *fl4 = &fl.u.ip4; #ifdef CONFIG_AF_RXRPC_IPV6 struct flowi6 *fl6 = &fl.u.ip6; #endif peer->if_mtu = 1500; if (peer->max_data < peer->if_mtu - peer->hdrsize) { trace_rxrpc_pmtud_reduce(peer, 0, peer->if_mtu - peer->hdrsize, rxrpc_pmtud_reduce_route); peer->max_data = peer->if_mtu - peer->hdrsize; } memset(&fl, 0, sizeof(fl)); switch (peer->srx.transport.family) { case AF_INET: rt = ip_route_output_ports( net, fl4, NULL, peer->srx.transport.sin.sin_addr.s_addr, 0, htons(7000), htons(7001), IPPROTO_UDP, 0, 0); if (IS_ERR(rt)) { _leave(" [route err %ld]", PTR_ERR(rt)); return; } dst = &rt->dst; break; #ifdef CONFIG_AF_RXRPC_IPV6 case AF_INET6: fl6->flowi6_iif = LOOPBACK_IFINDEX; fl6->flowi6_scope = RT_SCOPE_UNIVERSE; fl6->flowi6_proto = IPPROTO_UDP; memcpy(&fl6->daddr, &peer->srx.transport.sin6.sin6_addr, sizeof(struct in6_addr)); fl6->fl6_dport = htons(7001); fl6->fl6_sport = htons(7000); dst = ip6_route_output(net, NULL, fl6); if (dst->error) { _leave(" [route err %d]", dst->error); return; } break; #endif default: BUG(); } peer->if_mtu = dst_mtu(dst); peer->hdrsize += dst->header_len + dst->trailer_len; peer->tx_seg_max = dst->dev->gso_max_segs; dst_release(dst); peer->max_data = umin(RXRPC_JUMBO(1), peer->if_mtu - peer->hdrsize); peer->pmtud_good = 500; peer->pmtud_bad = peer->if_mtu - peer->hdrsize + 1; peer->pmtud_trial = umin(peer->max_data, peer->pmtud_bad - 1); peer->pmtud_pending = true; _leave(" [if_mtu %u]", peer->if_mtu); } /* * Allocate a peer. */ struct rxrpc_peer *rxrpc_alloc_peer(struct rxrpc_local *local, gfp_t gfp, enum rxrpc_peer_trace why) { struct rxrpc_peer *peer; _enter(""); peer = kzalloc_obj(struct rxrpc_peer, gfp); if (peer) { refcount_set(&peer->ref, 1); peer->local = rxrpc_get_local(local, rxrpc_local_get_peer); INIT_HLIST_HEAD(&peer->error_targets); peer->service_conns = RB_ROOT; seqlock_init(&peer->service_conn_lock); spin_lock_init(&peer->lock); peer->debug_id = atomic_inc_return(&rxrpc_debug_id); peer->recent_srtt_us = UINT_MAX; peer->cong_ssthresh = RXRPC_TX_MAX_WINDOW; trace_rxrpc_peer(peer->debug_id, 1, why); } _leave(" = %p", peer); return peer; } /* * Initialise peer record. */ static void rxrpc_init_peer(struct rxrpc_local *local, struct rxrpc_peer *peer, unsigned long hash_key) { peer->hash_key = hash_key; switch (peer->srx.transport.family) { case AF_INET: peer->hdrsize = sizeof(struct iphdr); break; #ifdef CONFIG_AF_RXRPC_IPV6 case AF_INET6: peer->hdrsize = sizeof(struct ipv6hdr); break; #endif default: BUG(); } switch (peer->srx.transport_type) { case SOCK_DGRAM: peer->hdrsize += sizeof(struct udphdr); break; default: BUG(); } peer->hdrsize += sizeof(struct rxrpc_wire_header); peer->max_data = peer->if_mtu - peer->hdrsize; } /* * Set up a new peer. */ static struct rxrpc_peer *rxrpc_create_peer(struct rxrpc_local *local, struct sockaddr_rxrpc *srx, unsigned long hash_key, gfp_t gfp) { struct rxrpc_peer *peer; _enter(""); peer = rxrpc_alloc_peer(local, gfp, rxrpc_peer_new_client); if (peer) { memcpy(&peer->srx, srx, sizeof(*srx)); rxrpc_init_peer(local, peer, hash_key); rxrpc_assess_MTU_size(local, peer); } _leave(" = %p", peer); return peer; } static void rxrpc_free_peer(struct rxrpc_peer *peer) { trace_rxrpc_peer(peer->debug_id, 0, rxrpc_peer_free); rxrpc_put_local(peer->local, rxrpc_local_put_peer); kfree_rcu(peer, rcu); } /* * Set up a new incoming peer. There shouldn't be any other matching peers * since we've already done a search in the list from the non-reentrant context * (the data_ready handler) that is the only place we can add new peers. * Called with interrupts disabled. */ void rxrpc_new_incoming_peer(struct rxrpc_local *local, struct rxrpc_peer *peer) { struct rxrpc_net *rxnet = local->rxnet; unsigned long hash_key; hash_key = rxrpc_peer_hash_key(local, &peer->srx); rxrpc_init_peer(local, peer, hash_key); spin_lock(&rxnet->peer_hash_lock); hash_add_rcu(rxnet->peer_hash, &peer->hash_link, hash_key); list_add_tail(&peer->keepalive_link, &rxnet->peer_keepalive_new); spin_unlock(&rxnet->peer_hash_lock); } /* * obtain a remote transport endpoint for the specified address */ struct rxrpc_peer *rxrpc_lookup_peer(struct rxrpc_local *local, struct sockaddr_rxrpc *srx, gfp_t gfp) { struct rxrpc_peer *peer, *candidate; struct rxrpc_net *rxnet = local->rxnet; unsigned long hash_key = rxrpc_peer_hash_key(local, srx); _enter("{%pISp}", &srx->transport); /* search the peer list first */ rcu_read_lock(); peer = __rxrpc_lookup_peer_rcu(local, srx, hash_key); if (peer && !rxrpc_get_peer_maybe(peer, rxrpc_peer_get_lookup_client)) peer = NULL; rcu_read_unlock(); if (!peer) { /* The peer is not yet present in hash - create a candidate * for a new record and then redo the search. */ candidate = rxrpc_create_peer(local, srx, hash_key, gfp); if (!candidate) { _leave(" = NULL [nomem]"); return NULL; } spin_lock_bh(&rxnet->peer_hash_lock); /* Need to check that we aren't racing with someone else */ peer = __rxrpc_lookup_peer_rcu(local, srx, hash_key); if (peer && !rxrpc_get_peer_maybe(peer, rxrpc_peer_get_lookup_client)) peer = NULL; if (!peer) { hash_add_rcu(rxnet->peer_hash, &candidate->hash_link, hash_key); list_add_tail(&candidate->keepalive_link, &rxnet->peer_keepalive_new); } spin_unlock_bh(&rxnet->peer_hash_lock); if (peer) rxrpc_free_peer(candidate); else peer = candidate; } _leave(" = %p {u=%d}", peer, refcount_read(&peer->ref)); return peer; } /* * Get a ref on a peer record. */ struct rxrpc_peer *rxrpc_get_peer(struct rxrpc_peer *peer, enum rxrpc_peer_trace why) { int r; __refcount_inc(&peer->ref, &r); trace_rxrpc_peer(peer->debug_id, r + 1, why); return peer; } /* * Get a ref on a peer record unless its usage has already reached 0. */ struct rxrpc_peer *rxrpc_get_peer_maybe(struct rxrpc_peer *peer, enum rxrpc_peer_trace why) { int r; if (peer) { if (__refcount_inc_not_zero(&peer->ref, &r)) trace_rxrpc_peer(peer->debug_id, r + 1, why); else peer = NULL; } return peer; } /* * Discard a peer record. */ static void __rxrpc_put_peer(struct rxrpc_peer *peer) { struct rxrpc_net *rxnet = peer->local->rxnet; ASSERT(hlist_empty(&peer->error_targets)); spin_lock_bh(&rxnet->peer_hash_lock); hash_del_rcu(&peer->hash_link); list_del_init(&peer->keepalive_link); spin_unlock_bh(&rxnet->peer_hash_lock); rxrpc_free_peer(peer); } /* * Drop a ref on a peer record. */ void rxrpc_put_peer(struct rxrpc_peer *peer, enum rxrpc_peer_trace why) { unsigned int debug_id; bool dead; int r; if (peer) { debug_id = peer->debug_id; dead = __refcount_dec_and_test(&peer->ref, &r); trace_rxrpc_peer(debug_id, r - 1, why); if (dead) __rxrpc_put_peer(peer); } } /* * Make sure all peer records have been discarded. */ void rxrpc_destroy_all_peers(struct rxrpc_net *rxnet) { struct rxrpc_peer *peer; int i; for (i = 0; i < HASH_SIZE(rxnet->peer_hash); i++) { if (hlist_empty(&rxnet->peer_hash[i])) continue; hlist_for_each_entry(peer, &rxnet->peer_hash[i], hash_link) { pr_err("Leaked peer %x {%u} %pISp\n", peer->debug_id, refcount_read(&peer->ref), &peer->srx.transport); } } } /** * rxrpc_kernel_get_call_peer - Get the peer address of a call * @sock: The socket on which the call is in progress. * @call: The call to query * * Get a record for the remote peer in a call. * * Return: The call's peer record. */ struct rxrpc_peer *rxrpc_kernel_get_call_peer(struct socket *sock, struct rxrpc_call *call) { return rxrpc_get_peer(call->peer, rxrpc_peer_get_application); } EXPORT_SYMBOL(rxrpc_kernel_get_call_peer); /** * rxrpc_kernel_get_srtt - Get a call's peer smoothed RTT * @peer: The peer to query * * Get the call's peer smoothed RTT. * * Return: The RTT in uS or %UINT_MAX if we have no samples. */ unsigned int rxrpc_kernel_get_srtt(const struct rxrpc_peer *peer) { return READ_ONCE(peer->recent_srtt_us); } EXPORT_SYMBOL(rxrpc_kernel_get_srtt); /** * rxrpc_kernel_remote_srx - Get the address of a peer