// SPDX-License-Identifier: GPL-2.0/* * linux/fs/lockd/host.c * * Management for NLM peer hosts. The nlm_host struct is shared * between client and server implementation. The only reason to * do so is to reduce code bloat. * * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de> */ #include <linux/types.h>#include <linux/slab.h>#include <linux/in.h>#include <linux/in6.h>#include <linux/sunrpc/clnt.h>#include <linux/sunrpc/addr.h>#include <linux/sunrpc/svc.h>#include <linux/mutex.h> #include <linux/sunrpc/svc_xprt.h> #include <net/ipv6.h> #include "lockd.h"#include "netns.h" #define NLMDBG_FACILITY NLMDBG_HOSTCACHE#define NLM_HOST_NRHASH 32#define NLM_HOST_REBIND (60 * HZ)#define NLM_HOST_EXPIRE (300 * HZ)#define NLM_HOST_COLLECT (120 * HZ) static struct hlist_head nlm_server_hosts[NLM_HOST_NRHASH];static struct hlist_head nlm_client_hosts[NLM_HOST_NRHASH]; #define for_each_host(host, chain, table) \ for ((chain) = (table); \ (chain) < (table) + NLM_HOST_NRHASH; ++(chain)) \ hlist_for_each_entry((host), (chain), h_hash) #define for_each_host_safe(host, next, chain, table) \ for ((chain) = (table); \ (chain) < (table) + NLM_HOST_NRHASH; ++(chain)) \ hlist_for_each_entry_safe((host), (next), \ (chain), h_hash) static unsigned long nrhosts;static DEFINE_MUTEX(nlm_host_mutex); static void nlm_gc_hosts(struct net *net); struct nlm_lookup_host_info { const int server; /* search for server|client */ const struct sockaddr *sap; /* address to search for */ const size_t salen; /* it's length */ const unsigned short protocol; /* transport to search for*/ const u32 version; /* NLM version to search for */ const char *hostname; /* remote's hostname */ const size_t hostname_len; /* it's length */ const int noresvport; /* use non-priv port */ struct net *net; /* network namespace to bind */ const struct cred *cred;}; /* * Hash function must work well on big- and little-endian platforms */static unsigned int __nlm_hash32(const __be32 n){ unsigned int hash = (__force u32)n ^ ((__force u32)n >> 16); return hash ^ (hash >> 8);} static unsigned int __nlm_hash_addr4(const struct sockaddr *sap){ const struct sockaddr_in *sin = (struct sockaddr_in *)sap; return __nlm_hash32(sin->sin_addr.s_addr);} static unsigned int __nlm_hash_addr6(const struct sockaddr *sap){ const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap; const struct in6_addr addr = sin6->sin6_addr; return __nlm_hash32(addr.s6_addr32[0]) ^ __nlm_hash32(addr.s6_addr32[1]) ^ __nlm_hash32(addr.s6_addr32[2]) ^ __nlm_hash32(addr.s6_addr32[3]);} static unsigned int nlm_hash_address(const struct sockaddr *sap){ unsigned int hash; switch (sap->sa_family) { case AF_INET: hash = __nlm_hash_addr4(sap); break; case AF_INET6: hash = __nlm_hash_addr6(sap); break; default: hash = 0; } return hash & (NLM_HOST_NRHASH - 1);} /* * Allocate and initialize an nlm_host. Common to both client and server. */static struct nlm_host *nlm_alloc_host(struct nlm_lookup_host_info *ni, struct nsm_handle *nsm){ struct nlm_host *host = NULL; unsigned long now = jiffies; if (nsm != NULL) refcount_inc(&nsm->sm_count); else { nsm = nsm_get_handle(ni->net, ni->sap, ni->salen, ni->hostname, ni->hostname_len); if (unlikely(nsm == NULL)) { dprintk("lockd: %s failed; no nsm handle\n", __func__); goto out; } } host = kmalloc_obj(*host); if (unlikely(host == NULL)) { dprintk("lockd: %s failed; no memory\n", __func__); nsm_release(nsm); goto out; } memcpy(nlm_addr(host), ni->sap, ni->salen); host->h_addrlen = ni->salen; rpc_set_port(nlm_addr(host), 0); host->h_srcaddrlen = 0; host->h_rpcclnt = NULL; host->h_name = nsm->sm_name; host->h_version = ni->version; host->h_proto = ni->protocol; host->h_reclaiming = 0; host->h_server = ni->server; host->h_noresvport = ni->noresvport; host->h_inuse = 0; init_waitqueue_head(&host->h_gracewait); init_rwsem(&host->h_rwsem); host->h_state = 0; host->h_nsmstate = 0; host->h_pidcount = 0; refcount_set(&host->h_count, 1); mutex_init(&host->h_mutex); host->h_nextrebind = now + NLM_HOST_REBIND; host->h_expires = now + NLM_HOST_EXPIRE; INIT_LIST_HEAD(&host->h_lockowners); spin_lock_init(&host->h_lock); INIT_LIST_HEAD(&host->h_granted); INIT_LIST_HEAD(&host->h_reclaim); host->h_nsmhandle = nsm; host->h_addrbuf = nsm->sm_addrbuf; host->net = ni->net; host->h_cred = get_cred(ni->cred); strscpy(host->nodename, utsname()->nodename, sizeof(host->nodename)); out: return host;} /* * Destroy an nlm_host and free associated resources * * Caller must hold nlm_host_mutex. */static void nlm_destroy_host_locked(struct nlm_host *host){ struct rpc_clnt *clnt; struct lockd_net *ln = net_generic(host->net, lockd_net_id); dprintk("lockd: destroy host %s\n", host->h_name); hlist_del_init(&host->h_hash); nsm_unmonitor(host); nsm_release(host->h_nsmhandle); clnt = host->h_rpcclnt; if (clnt != NULL) rpc_shutdown_client(clnt); put_cred(host->h_cred); kfree(host); ln->nrhosts--; nrhosts--;} /** * nlmclnt_lookup_host - Find an NLM host handle matching a remote server * @sap: network address of server * @salen: length of server address * @protocol: transport protocol to use * @version: NLM protocol version * @hostname: '\0'-terminated hostname of server * @noresvport: 1 if non-privileged port should be used * @net: pointer to net namespace * @cred: pointer to cred * * Returns an nlm_host structure that matches the passed-in * [server address, transport protocol, NLM version, server hostname]. * If one doesn't already exist in the host cache, a new handle is * created and returned. */struct nlm_host *nlmclnt_lookup_host(const struct sockaddr *sap, const size_t salen, const unsigned short protocol, const u32 version, const char *hostname, int noresvport, struct net *net, const struct cred *cred){ struct nlm_lookup_host_info ni = { .server = 0, .sap = sap, .salen = salen, .protocol = protocol, .version = version, .hostname = hostname, .hostname_len = strlen(hostname), .noresvport = noresvport, .net = net, .cred = cred, }; struct hlist_head *chain; struct nlm_host *host; struct nsm_handle *nsm = NULL; struct lockd_net *ln = net_generic(net, lockd_net_id); dprintk("lockd: %s(host='%s', vers=%u, proto=%s)\n", __func__, (hostname ? hostname : "<none>"), version, (protocol == IPPROTO_UDP ? "udp" : "tcp")); mutex_lock(&nlm_host_mutex); chain = &nlm_client_hosts[nlm_hash_address(sap)]; hlist_for_each_entry(host, chain, h_hash) { if (host->net != net) continue; if (!rpc_cmp_addr(nlm_addr(host), sap)) continue; /* Same address. Share an NSM handle if we already have one */ if (nsm == NULL) nsm = host->h_nsmhandle; if (host->h_proto != protocol) continue; if (host->h_version != version) continue; nlm_get_host(host); dprintk("lockd: %s found host %s (%s)\n", __func__, host->h_name, host->h_addrbuf); goto out; } host = nlm_alloc_host(&ni, nsm); if (unlikely(host == NULL)) goto out; hlist_add_head(&host->h_hash, chain); ln->nrhosts++; nrhosts++; dprintk("lockd: %s created host %s (%s)\n", __func__, host->h_name, host->h_addrbuf); out: mutex_unlock(&nlm_host_mutex); return host;} /** * nlmclnt_release_host - release client nlm_host * @host: nlm_host to release * */void nlmclnt_release_host(struct nlm_host *host){ if (host == NULL) return; dprintk("lockd: release client host %s\n", host->h_name); WARN_ON_ONCE(host->h_server); if (refcount_dec_and_mutex_lock(&host->h_count, &nlm_host_mutex)) { WARN_ON_ONCE(!list_empty(&host->h_lockowners)); WARN_ON_ONCE(!list_empty(&host->h_granted)); WARN_ON_ONCE(!list_empty(&host->h_reclaim)); nlm_destroy_host_locked(host); mutex_unlock(&nlm_host_mutex); }} /* Callback for rpc_cancel_tasks() - matches all tasks for cancellation */static bool nlmclnt_match_all(const struct rpc_task *task, const void *data){ return true;} /** * nlmclnt_shutdown_rpc_clnt - safely shut down NLM client RPC operations * @host: nlm_host to shut down * * Cancels outstanding RPC tasks and marks the client as shut down. * Synchronizes with nlmclnt_release_host() via nlm_host_mutex to prevent * races between shutdown and host destruction. Safe to call if h_rpcclnt * is NULL or already shut down. */void nlmclnt_shutdown_rpc_clnt(struct nlm_host *host){ struct rpc_clnt *clnt; mutex_lock(&nlm_host_mutex); clnt = host->h_rpcclnt; if (clnt) { clnt->cl_shutdown = 1; rpc_cancel_tasks(clnt, -EIO, nlmclnt_match_all, NULL); } mutex_unlock(&nlm_host_mutex);}EXPORT_SYMBOL_GPL(nlmclnt_shutdown_rpc_clnt); /** * nlmsvc_lookup_host - Find an NLM host handle matching a remote client * @rqstp: incoming NLM request * @hostname: name of client host * @hostname_len: length of client hostname * * Returns an nlm_host structure that matches the [client address, * transport protocol, NLM version, client hostname] of the passed-in * NLM request. If one doesn't already exist in the host cache, a * new handle is created and returned. * * Before possibly creating a new nlm_host, construct a sockaddr * for a specific source address in case the local system has * multiple network addresses. The family of the address in * rq_daddr is guaranteed to be the same as the family of the * address in rq_addr, so it's safe to use the same family for * the source address. */struct nlm_host *nlmsvc_lookup_host(const struct svc_rqst *rqstp, const char *hostname, const size_t hostname_len){ struct hlist_head *chain; struct nlm_host *host = NULL; struct nsm_handle *nsm = NULL; struct sockaddr *src_sap = svc_daddr(rqstp); size_t src_len = rqstp->rq_daddrlen; struct net *net = SVC_NET(rqstp); struct nlm_lookup_host_info ni = { .server = 1, .sap = svc_addr(rqstp), .salen = rqstp->rq_addrlen, .protocol = rqstp->rq_prot, .version = rqstp->rq_vers, .hostname = hostname, .hostname_len = hostname_len, .net = net, }; struct lockd_net *ln = net_generic(net, lockd_net_id); dprintk("lockd: %s(host='%.*s', vers=%u, proto=%s)\n", __func__, (int)hostname_len, hostname, rqstp->rq_vers, (rqstp->rq_prot == IPPROTO_UDP ? "udp" : "tcp")); mutex_lock(&nlm_host_mutex); if (time_after_eq(jiffies, ln->next_gc)) nlm_gc_hosts(net); chain = &nlm_server_hosts[nlm_hash_address(ni.sap)]; hlist_for_each_entry(host, chain, h_hash) { if (host->net != net) continue; if (!rpc_cmp_addr(nlm_addr(host), ni.sap)) continue; /* Same address. Share an NSM handle if we already have one */ if (nsm == NULL) nsm = host->h_nsmhandle; if (host->h_proto != ni.protocol) continue; if (host->h_version != ni.version) continue; if (!rpc_cmp_addr(nlm_srcaddr(host), src_sap)) continue; /* Move to head of hash chain. */ hlist_del(&host->h_hash); hlist_add_head(&host->h_hash, chain); nlm_get_host(host); dprintk("lockd: %s found host %s (%s)\n", __func__, host->h_name, host->h_addrbuf); goto out; } host = nlm_alloc_host(&ni, nsm); if (unlikely(host == NULL)) goto out; memcpy(nlm_srcaddr(host), src_sap, src_len); host->h_srcaddrlen = src_len; hlist_add_head(&host->h_hash, chain); ln->nrhosts++; nrhosts++; refcount_inc(&host->h_count); dprintk("lockd: %s created host %s (%s)\n", __func__, host->h_name, host->h_addrbuf); out: mutex_unlock(&nlm_host_mutex); return host;} /** * nlmsvc_release_host - release server nlm_host * @host: nlm_host to release * * Host is destroyed later in nlm_gc_host(). */void nlmsvc_release_host(struct nlm_host *host){ if (host == NULL) return; dprintk("lockd: release server host %s\n", host->h_name); WARN_ON_ONCE(!host->h_server); refcount_dec(&host->h_count);} /* * Create the NLM RPC client for an NLM peer */struct rpc_clnt *nlm_bind_host(struct nlm_host *host){ struct rpc_clnt *clnt; dprintk("lockd: nlm_bind_host %s (%s)\n", host->h_name, host->h_addrbuf); /* Lock host handle */ mutex_lock(&host->h_mutex); /* If we've already created an RPC client, check whether * RPC rebind is required */ if ((clnt = host->h_rpcclnt) != NULL) { nlm_rebind_host(host); } else { unsigned long increment = nlm_timeout * HZ; struct rpc_timeout timeparms = { .to_initval = increment, .to_increment = increment, .to_maxval = increment * 6UL, .to_retries = 5U, }; struct rpc_create_args args = { .net = host->net, .protocol = host->h_proto, .address = nlm_addr(host), .addrsize = host->h_addrlen, .timeout = &timeparms, .servername = host->h_name, .program = &nlm_program, .version = host->h_version, .authflavor = RPC_AUTH_UNIX, .flags = (RPC_CLNT_CREATE_NOPING | RPC_CLNT_CREATE_AUTOBIND | RPC_CLNT_CREATE_REUSEPORT), .cred = host->h_cred, }; /* * lockd retries server side blocks automatically so we want * those to be soft RPC calls. Client side calls need to be * hard RPC tasks. */ if (!host->h_server)Lines 1–500 of 723. Load more
// SPDX-License-Identifier: GPL-2.0 /* * linux/fs/lockd/host.c * * Management for NLM peer hosts. The nlm_host struct is shared * between client and server implementation. The only reason to * do so is to reduce code bloat. * * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de> */ #include <linux/types.h> #include <linux/slab.h> #include <linux/in.h> #include <linux/in6.h> #include <linux/sunrpc/clnt.h> #include <linux/sunrpc/addr.h> #include <linux/sunrpc/svc.h> #include <linux/mutex.h> #include <linux/sunrpc/svc_xprt.h> #include <net/ipv6.h> #include "lockd.h" #include "netns.h" #define NLMDBG_FACILITY NLMDBG_HOSTCACHE #define NLM_HOST_NRHASH 32 #define NLM_HOST_REBIND (60 * HZ) #define NLM_HOST_EXPIRE (300 * HZ) #define NLM_HOST_COLLECT (120 * HZ) static struct hlist_head nlm_server_hosts[NLM_HOST_NRHASH]; static struct hlist_head nlm_client_hosts[NLM_HOST_NRHASH]; #define for_each_host(host, chain, table) \ for ((chain) = (table); \ (chain) < (table) + NLM_HOST_NRHASH; ++(chain)) \ hlist_for_each_entry((host), (chain), h_hash) #define for_each_host_safe(host, next, chain, table) \ for ((chain) = (table); \ (chain) < (table) + NLM_HOST_NRHASH; ++(chain)) \ hlist_for_each_entry_safe((host), (next), \ (chain), h_hash) static unsigned long nrhosts; static DEFINE_MUTEX(nlm_host_mutex); static void nlm_gc_hosts(struct net *net); struct nlm_lookup_host_info { const int server; /* search for server|client */ const struct sockaddr *sap; /* address to search for */ const size_t salen; /* it's length */ const unsigned short protocol; /* transport to search for*/ const u32 version; /* NLM version to search for */ const char *hostname; /* remote's hostname */ const size_t hostname_len; /* it's length */ const int noresvport; /* use non-priv port */ struct net *net; /* network namespace to bind */ const struct cred *cred; }; /* * Hash function must work well on big- and little-endian platforms */ static unsigned int __nlm_hash32(const __be32 n) { unsigned int hash = (__force u32)n ^ ((__force u32)n >> 16); return hash ^ (hash >> 8); } static unsigned int __nlm_hash_addr4(const struct sockaddr *sap) { const struct sockaddr_in *sin = (struct sockaddr_in *)sap; return __nlm_hash32(sin->sin_addr.s_addr); } static unsigned int __nlm_hash_addr6(const struct sockaddr *sap) { const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap; const struct in6_addr addr = sin6->sin6_addr; return __nlm_hash32(addr.s6_addr32[0]) ^ __nlm_hash32(addr.s6_addr32[1]) ^ __nlm_hash32(addr.s6_addr32[2]) ^ __nlm_hash32(addr.s6_addr32[3]); } static unsigned int nlm_hash_address(const struct sockaddr *sap) { unsigned int hash; switch (sap->sa_family) { case AF_INET: hash = __nlm_hash_addr4(sap); break; case AF_INET6: hash = __nlm_hash_addr6(sap); break; default: hash = 0; } return hash & (NLM_HOST_NRHASH - 1); } /* * Allocate and initialize an nlm_host. Common to both client and server. */ static struct nlm_host *nlm_alloc_host(struct nlm_lookup_host_info *ni, struct nsm_handle *nsm) { struct nlm_host *host = NULL; unsigned long now = jiffies; if (nsm != NULL) refcount_inc(&nsm->sm_count); else { nsm = nsm_get_handle(ni->net, ni->sap, ni->salen, ni->hostname, ni->hostname_len); if (unlikely(nsm == NULL)) { dprintk("lockd: %s failed; no nsm handle\n", __func__); goto out; } } host = kmalloc_obj(*host); if (unlikely(host == NULL)) { dprintk("lockd: %s failed; no memory\n", __func__); nsm_release(nsm); goto out; } memcpy(nlm_addr(host), ni->sap, ni->salen); host->h_addrlen = ni->salen; rpc_set_port(nlm_addr(host), 0); host->h_srcaddrlen = 0; host->h_rpcclnt = NULL; host->h_name = nsm->sm_name; host->h_version = ni->version; host->h_proto = ni->protocol; host->h_reclaiming = 0; host->h_server = ni->server; host->h_noresvport = ni->noresvport; host->h_inuse = 0; init_waitqueue_head(&host->h_gracewait); init_rwsem(&host->h_rwsem); host->h_state = 0; host->h_nsmstate = 0; host->h_pidcount = 0; refcount_set(&host->h_count, 1); mutex_init(&host->h_mutex); host->h_nextrebind = now + NLM_HOST_REBIND; host->h_expires = now + NLM_HOST_EXPIRE; INIT_LIST_HEAD(&host->h_lockowners); spin_lock_init(&host->h_lock); INIT_LIST_HEAD(&host->h_granted); INIT_LIST_HEAD(&host->h_reclaim); host->h_nsmhandle = nsm; host->h_addrbuf = nsm->sm_addrbuf; host->net = ni->net; host->h_cred = get_cred(ni->cred); strscpy(host->nodename, utsname()->nodename, sizeof(host->nodename)); out: return host; } /* * Destroy an nlm_host and free associated resources * * Caller must hold nlm_host_mutex. */ static void nlm_destroy_host_locked(struct nlm_host *host) { struct rpc_clnt *clnt; struct lockd_net *ln = net_generic(host->net, lockd_net_id); dprintk("lockd: destroy host %s\n", host->h_name); hlist_del_init(&host->h_hash); nsm_unmonitor(host); nsm_release(host->h_nsmhandle); clnt = host->h_rpcclnt; if (clnt != NULL) rpc_shutdown_client(clnt); put_cred(host->h_cred); kfree(host); ln->nrhosts--; nrhosts--; } /** * nlmclnt_lookup_host - Find an NLM host handle matching a remote server * @sap: network address of server * @salen: length of server address * @protocol: transport protocol to use * @version: NLM protocol version * @hostname: '\0'-terminated hostname of server * @noresvport: 1 if non-privileged port should be used * @net: pointer to net namespace * @cred: pointer to cred * * Returns an nlm_host structure that matches the passed-in * [server address, transport protocol, NLM version, server hostname]. * If one doesn't already exist in the host cache, a new handle is * created and returned. */ struct nlm_host *nlmclnt_lookup_host(const struct sockaddr *sap, const size_t salen, const unsigned short protocol, const u32 version, const char *hostname, int noresvport, struct net *net, const struct cred *cred) { struct nlm_lookup_host_info ni = { .server = 0, .sap = sap, .salen = salen, .protocol = protocol, .version = version, .hostname = hostname, .hostname_len = strlen(hostname), .noresvport = noresvport, .net = net, .cred = cred, }; struct hlist_head *chain; struct nlm_host *host; struct nsm_handle *nsm = NULL; struct lockd_net *ln = net_generic(net, lockd_net_id); dprintk("lockd: %s(host='%s', vers=%u, proto=%s)\n", __func__, (hostname ? hostname : "<none>"), version, (protocol == IPPROTO_UDP ? "udp" : "tcp")); mutex_lock(&nlm_host_mutex); chain = &nlm_client_hosts[nlm_hash_address(sap)]; hlist_for_each_entry(host, chain, h_hash) { if (host->net != net) continue; if (!rpc_cmp_addr(nlm_addr(host), sap)) continue; /* Same address. Share an NSM handle if we already have one */ if (nsm == NULL) nsm = host->h_nsmhandle; if (host->h_proto != protocol) continue; if (host->h_version != version) continue; nlm_get_host(host); dprintk("lockd: %s found host %s (%s)\n", __func__, host->h_name, host->h_addrbuf); goto out; } host = nlm_alloc_host(&ni, nsm); if (unlikely(host == NULL)) goto out; hlist_add_head(&host->h_hash, chain); ln->nrhosts++; nrhosts++; dprintk("lockd: %s created host %s (%s)\n", __func__, host->h_name, host->h_addrbuf); out: mutex_unlock(&nlm_host_mutex); return host; } /** * nlmclnt_release_host - release client nlm_host * @host: nlm_host to release * */ void nlmclnt_release_host(struct nlm_host *host) { if (host == NULL) return; dprintk("lockd: release client host %s\n", host->h_name); WARN_ON_ONCE(host->h_server); if (refcount_dec_and_mutex_lock(&host->h_count, &nlm_host_mutex)) { WARN_ON_ONCE(!list_empty(&host->h_lockowners)); WARN_ON_ONCE(!list_empty(&host->h_granted)); WARN_ON_ONCE(!list_empty(&host->h_reclaim)); nlm_destroy_host_locked(host); mutex_unlock(&nlm_host_mutex); } } /* Callback for rpc_cancel_tasks() - matches all tasks for cancellation */ static bool nlmclnt_match_all(const struct rpc_task *task, const void *data) { return true; } /** * nlmclnt_shutdown_rpc_clnt - safely shut down NLM client RPC operations * @host: nlm_host to shut down * * Cancels outstanding RPC tasks and marks the client as shut down. * Synchronizes with nlmclnt_release_host() via nlm_host_mutex to prevent * races between shutdown and host destruction. Safe to call if h_rpcclnt * is NULL or already shut down. */ void nlmclnt_shutdown_rpc_clnt(struct nlm_host *host) { struct rpc_clnt *clnt; mutex_lock(&nlm_host_mutex); clnt = host->h_rpcclnt; if (clnt) { clnt->cl_shutdown = 1; rpc_cancel_tasks(clnt, -EIO, nlmclnt_match_all, NULL); } mutex_unlock(&nlm_host_mutex); } EXPORT_SYMBOL_GPL(nlmclnt_shutdown_rpc_clnt); /** * nlmsvc_lookup_host - Find an NLM host handle matching a remote client * @rqstp: incoming NLM request * @hostname: name of client host * @hostname_len: length of client hostname * * Returns an nlm_host structure that matches the [client address, * transport protocol, NLM version, client hostname] of the passed-in * NLM request. If one doesn't already exist in the host cache, a * new handle is created and returned. * * Before possibly creating a new nlm_host, construct a sockaddr * for a specific source address in case the local system has * multiple network addresses. The family of the address in * rq_daddr is guaranteed to be the same as the family of the * address in rq_addr, so it's safe to use the same family for * the source address. */ struct nlm_host *nlmsvc_lookup_host(const struct svc_rqst *rqstp, const char *hostname, const size_t hostname_len) { struct hlist_head *chain; struct nlm_host *host = NULL; struct nsm_handle *nsm = NULL; struct sockaddr *src_sap = svc_daddr(rqstp); size_t src_len = rqstp->rq_daddrlen; struct net *net = SVC_NET(rqstp); struct nlm_lookup_host_info ni = { .server = 1, .sap = svc_addr(rqstp), .salen = rqstp->rq_addrlen, .protocol = rqstp->rq_prot, .version = rqstp->rq_vers, .hostname = hostname, .hostname_len = hostname_len, .net = net, }; struct lockd_net *ln = net_generic(net, lockd_net_id); dprintk("lockd: %s(host='%.*s', vers=%u, proto=%s)\n", __func__, (int)hostname_len, hostname, rqstp->rq_vers, (rqstp->rq_prot == IPPROTO_UDP ? "udp" : "tcp")); mutex_lock(&nlm_host_mutex); if (time_after_eq(jiffies, ln->next_gc)) nlm_gc_hosts(net); chain = &nlm_server_hosts[nlm_hash_address(ni.sap)]; hlist_for_each_entry(host, chain, h_hash) { if (host->net != net) continue; if (!rpc_cmp_addr(nlm_addr(host), ni.sap)) continue; /* Same address. Share an NSM handle if we already have one */ if (nsm == NULL) nsm = host->h_nsmhandle; if (host->h_proto != ni.protocol) continue; if (host->h_version != ni.version) continue; if (!rpc_cmp_addr(nlm_srcaddr(host), src_sap)) continue; /* Move to head of hash chain. */ hlist_del(&host->h_hash); hlist_add_head(&host->h_hash, chain); nlm_get_host(host); dprintk("lockd: %s found host %s (%s)\n", __func__, host->h_name, host->h_addrbuf); goto out; } host = nlm_alloc_host(&ni, nsm); if (unlikely(host == NULL)) goto out; memcpy(nlm_srcaddr(host), src_sap, src_len); host->h_srcaddrlen = src_len; hlist_add_head(&host->h_hash, chain); ln->nrhosts++; nrhosts++; refcount_inc(&host->h_count); dprintk("lockd: %s created host %s (%s)\n", __func__, host->h_name, host->h_addrbuf); out: mutex_unlock(&nlm_host_mutex); return host; } /** * nlmsvc_release_host - release server nlm_host * @host: nlm_host to release * * Host is destroyed later in nlm_gc_host(). */ void nlmsvc_release_host(struct nlm_host *host) { if (host == NULL) return; dprintk("lockd: release server host %s\n", host->h_name); WARN_ON_ONCE(!host->h_server); refcount_dec(&host->h_count); } /* * Create the NLM RPC client for an NLM peer */ struct rpc_clnt * nlm_bind_host(struct nlm_host *host) { struct rpc_clnt *clnt; dprintk("lockd: nlm_bind_host %s (%s)\n", host->h_name, host->h_addrbuf); /* Lock host handle */ mutex_lock(&host->h_mutex); /* If we've already created an RPC client, check whether * RPC rebind is required */ if ((clnt = host->h_rpcclnt) != NULL) { nlm_rebind_host(host); } else { unsigned long increment = nlm_timeout * HZ; struct rpc_timeout timeparms = { .to_initval = increment, .to_increment = increment, .to_maxval = increment * 6UL, .to_retries = 5U, }; struct rpc_create_args args = { .net = host->net, .protocol = host->h_proto, .address = nlm_addr(host), .addrsize = host->h_addrlen, .timeout = &timeparms, .servername = host->h_name, .program = &nlm_program, .version = host->h_version, .authflavor = RPC_AUTH_UNIX, .flags = (RPC_CLNT_CREATE_NOPING | RPC_CLNT_CREATE_AUTOBIND | RPC_CLNT_CREATE_REUSEPORT), .cred = host->h_cred, }; /* * lockd retries server side blocks automatically so we want * those to be soft RPC calls. Client side calls need to be * hard RPC tasks. */ if (!host->h_server)