diff options
Diffstat (limited to 'fs/afs/fs_probe.c')
| -rw-r--r-- | fs/afs/fs_probe.c | 584 |
1 files changed, 422 insertions, 162 deletions
diff --git a/fs/afs/fs_probe.c b/fs/afs/fs_probe.c index 3a9eaec06756..e0030ac74ea0 100644 --- a/fs/afs/fs_probe.c +++ b/fs/afs/fs_probe.c @@ -1,29 +1,134 @@ +// SPDX-License-Identifier: GPL-2.0-or-later /* AFS fileserver probing * - * Copyright (C) 2018 Red Hat, Inc. All Rights Reserved. + * Copyright (C) 2018, 2020 Red Hat, Inc. All Rights Reserved. * Written by David Howells (dhowells@redhat.com) - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public Licence - * as published by the Free Software Foundation; either version - * 2 of the Licence, or (at your option) any later version. */ #include <linux/sched.h> #include <linux/slab.h> #include "afs_fs.h" #include "internal.h" +#include "protocol_afs.h" #include "protocol_yfs.h" -static bool afs_fs_probe_done(struct afs_server *server) +static unsigned int afs_fs_probe_fast_poll_interval = 30 * HZ; +static unsigned int afs_fs_probe_slow_poll_interval = 5 * 60 * HZ; + +struct afs_endpoint_state *afs_get_endpoint_state(struct afs_endpoint_state *estate, + enum afs_estate_trace where) +{ + if (estate) { + int r; + + __refcount_inc(&estate->ref, &r); + trace_afs_estate(estate->server_id, estate->probe_seq, r, where); + } + return estate; +} + +static void afs_endpoint_state_rcu(struct rcu_head *rcu) +{ + struct afs_endpoint_state *estate = container_of(rcu, struct afs_endpoint_state, rcu); + + trace_afs_estate(estate->server_id, estate->probe_seq, refcount_read(&estate->ref), + afs_estate_trace_free); + afs_put_addrlist(estate->addresses, afs_alist_trace_put_estate); + kfree(estate); +} + +void afs_put_endpoint_state(struct afs_endpoint_state *estate, enum afs_estate_trace where) +{ + if (estate) { + unsigned int server_id = estate->server_id, probe_seq = estate->probe_seq; + bool dead; + int r; + + dead = __refcount_dec_and_test(&estate->ref, &r); + trace_afs_estate(server_id, probe_seq, r, where); + if (dead) + call_rcu(&estate->rcu, afs_endpoint_state_rcu); + } +} + +/* + * Start the probe polling timer. We have to supply it with an inc on the + * outstanding server count. + */ +static void afs_schedule_fs_probe(struct afs_net *net, + struct afs_server *server, bool fast) +{ + unsigned long atj; + + if (!net->live) + return; + + atj = server->probed_at; + atj += fast ? afs_fs_probe_fast_poll_interval : afs_fs_probe_slow_poll_interval; + + afs_inc_servers_outstanding(net); + if (timer_reduce(&net->fs_probe_timer, atj)) + afs_dec_servers_outstanding(net); +} + +/* + * Handle the completion of a set of probes. + */ +static void afs_finished_fs_probe(struct afs_net *net, struct afs_server *server, + struct afs_endpoint_state *estate) +{ + bool responded = test_bit(AFS_ESTATE_RESPONDED, &estate->flags); + + write_seqlock(&net->fs_lock); + if (responded) { + list_add_tail(&server->probe_link, &net->fs_probe_slow); + } else { + server->rtt = UINT_MAX; + clear_bit(AFS_SERVER_FL_RESPONDING, &server->flags); + list_add_tail(&server->probe_link, &net->fs_probe_fast); + } + + write_sequnlock(&net->fs_lock); + + afs_schedule_fs_probe(net, server, !responded); +} + +/* + * Handle the completion of a probe. + */ +static void afs_done_one_fs_probe(struct afs_net *net, struct afs_server *server, + struct afs_endpoint_state *estate) +{ + _enter(""); + + if (atomic_dec_and_test(&estate->nr_probing)) + afs_finished_fs_probe(net, server, estate); + + wake_up_all(&server->probe_wq); +} + +/* + * Handle inability to send a probe due to ENOMEM when trying to allocate a + * call struct. + */ +static void afs_fs_probe_not_done(struct afs_net *net, + struct afs_server *server, + struct afs_endpoint_state *estate, + int index) { - if (!atomic_dec_and_test(&server->probe_outstanding)) - return false; + _enter(""); + + trace_afs_io_error(0, -ENOMEM, afs_io_error_fs_probe_fail); + spin_lock(&server->probe_lock); - wake_up_var(&server->probe_outstanding); - clear_bit_unlock(AFS_SERVER_FL_PROBING, &server->flags); - wake_up_bit(&server->flags, AFS_SERVER_FL_PROBING); - return true; + set_bit(AFS_ESTATE_LOCAL_FAILURE, &estate->flags); + if (estate->error == 0) + estate->error = -ENOMEM; + + set_bit(index, &estate->failed_set); + + spin_unlock(&server->probe_lock); + return afs_done_one_fs_probe(net, server, estate); } /* @@ -32,33 +137,35 @@ static bool afs_fs_probe_done(struct afs_server *server) */ void afs_fileserver_probe_result(struct afs_call *call) { - struct afs_addr_list *alist = call->alist; - struct afs_server *server = call->reply[0]; - unsigned int server_index = (long)call->reply[1]; - unsigned int index = call->addr_ix; - unsigned int rtt = UINT_MAX; - bool have_result = false; - u64 _rtt; + struct afs_endpoint_state *estate = call->probe; + struct afs_addr_list *alist = estate->addresses; + struct afs_address *addr = &alist->addrs[call->probe_index]; + struct afs_server *server = call->server; + unsigned int index = call->probe_index; + unsigned int rtt_us = -1, cap0; int ret = call->error; _enter("%pU,%u", &server->uuid, index); + WRITE_ONCE(addr->last_error, ret); + spin_lock(&server->probe_lock); switch (ret) { case 0: - server->probe.error = 0; + estate->error = 0; goto responded; case -ECONNABORTED: - if (!server->probe.responded) { - server->probe.abort_code = call->abort_code; - server->probe.error = ret; + if (!test_bit(AFS_ESTATE_RESPONDED, &estate->flags)) { + estate->abort_code = call->abort_code; + estate->error = ret; } goto responded; case -ENOMEM: case -ENONET: - server->probe.local_failure = true; - afs_io_error(call, afs_io_error_fs_probe_fail); + clear_bit(index, &estate->responsive_set); + set_bit(AFS_ESTATE_LOCAL_FAILURE, &estate->flags); + trace_afs_io_error(call->debug_id, ret, afs_io_error_fs_probe_fail); goto out; case -ECONNRESET: /* Responded, but call expired. */ case -ERFKILL: @@ -70,180 +177,179 @@ void afs_fileserver_probe_result(struct afs_call *call) case -ETIMEDOUT: case -ETIME: default: - clear_bit(index, &alist->responded); - set_bit(index, &alist->failed); - if (!server->probe.responded && - (server->probe.error == 0 || - server->probe.error == -ETIMEDOUT || - server->probe.error == -ETIME)) - server->probe.error = ret; - afs_io_error(call, afs_io_error_fs_probe_fail); + clear_bit(index, &estate->responsive_set); + set_bit(index, &estate->failed_set); + if (!test_bit(AFS_ESTATE_RESPONDED, &estate->flags) && + (estate->error == 0 || + estate->error == -ETIMEDOUT || + estate->error == -ETIME)) + estate->error = ret; + trace_afs_io_error(call->debug_id, ret, afs_io_error_fs_probe_fail); goto out; } responded: - set_bit(index, &alist->responded); - clear_bit(index, &alist->failed); + clear_bit(index, &estate->failed_set); if (call->service_id == YFS_FS_SERVICE) { - server->probe.is_yfs = true; + set_bit(AFS_ESTATE_IS_YFS, &estate->flags); set_bit(AFS_SERVER_FL_IS_YFS, &server->flags); - alist->addrs[index].srx_service = call->service_id; + server->service_id = call->service_id; } else { - server->probe.not_yfs = true; - if (!server->probe.is_yfs) { + set_bit(AFS_ESTATE_NOT_YFS, &estate->flags); + if (!test_bit(AFS_ESTATE_IS_YFS, &estate->flags)) { clear_bit(AFS_SERVER_FL_IS_YFS, &server->flags); - alist->addrs[index].srx_service = call->service_id; + server->service_id = call->service_id; } + cap0 = ntohl(call->tmp); + if (cap0 & AFS3_VICED_CAPABILITY_64BITFILES) + set_bit(AFS_SERVER_FL_HAS_FS64, &server->flags); + else + clear_bit(AFS_SERVER_FL_HAS_FS64, &server->flags); } - /* Get the RTT and scale it to fit into a 32-bit value that represents - * over a minute of time so that we can access it with one instruction - * on a 32-bit system. - */ - _rtt = rxrpc_kernel_get_rtt(call->net->socket, call->rxcall); - _rtt /= 64; - rtt = (_rtt > UINT_MAX) ? UINT_MAX : _rtt; - if (rtt < server->probe.rtt) { - server->probe.rtt = rtt; + rtt_us = rxrpc_kernel_get_srtt(addr->peer); + if (rtt_us < estate->rtt) { + estate->rtt = rtt_us; + server->rtt = rtt_us; alist->preferred = index; - have_result = true; } smp_wmb(); /* Set rtt before responded. */ - server->probe.responded = true; - set_bit(AFS_SERVER_FL_PROBED, &server->flags); + set_bit(AFS_ESTATE_RESPONDED, &estate->flags); + set_bit(index, &estate->responsive_set); + set_bit(AFS_SERVER_FL_RESPONDING, &server->flags); out: spin_unlock(&server->probe_lock); - _debug("probe [%u][%u] %pISpc rtt=%u ret=%d", - server_index, index, &alist->addrs[index].transport, - (unsigned int)rtt, ret); + trace_afs_fs_probe(server, false, estate, index, call->error, call->abort_code, rtt_us); + _debug("probe[%x] %pU [%u] %pISpc rtt=%d ret=%d", + estate->probe_seq, &server->uuid, index, + rxrpc_kernel_remote_addr(alist->addrs[index].peer), + rtt_us, ret); - have_result |= afs_fs_probe_done(server); - if (have_result) { - server->probe.have_result = true; - wake_up_var(&server->probe.have_result); - wake_up_all(&server->probe_wq); - } + return afs_done_one_fs_probe(call->net, server, estate); } /* * Probe all of a fileserver's addresses to find out the best route and to * query its capabilities. */ -static int afs_do_probe_fileserver(struct afs_net *net, - struct afs_server *server, - struct key *key, - unsigned int server_index, - struct afs_error *_e) +int afs_fs_probe_fileserver(struct afs_net *net, struct afs_server *server, + struct afs_addr_list *new_alist, struct key *key) { - struct afs_addr_cursor ac = { - .index = 0, - }; - bool in_progress = false; - int err; + struct afs_endpoint_state *estate, *old; + struct afs_addr_list *old_alist = NULL, *alist; + unsigned long unprobed; _enter("%pU", &server->uuid); - read_lock(&server->fs_lock); - ac.alist = rcu_dereference_protected(server->addresses, - lockdep_is_held(&server->fs_lock)); - read_unlock(&server->fs_lock); + estate = kzalloc(sizeof(*estate), GFP_KERNEL); + if (!estate) + return -ENOMEM; + + refcount_set(&estate->ref, 2); + estate->server_id = server->debug_id; + estate->rtt = UINT_MAX; - atomic_set(&server->probe_outstanding, ac.alist->nr_addrs); - memset(&server->probe, 0, sizeof(server->probe)); - server->probe.rtt = UINT_MAX; + write_lock(&server->fs_lock); - for (ac.index = 0; ac.index < ac.alist->nr_addrs; ac.index++) { - err = afs_fs_get_capabilities(net, server, &ac, key, server_index, - true); - if (err == -EINPROGRESS) - in_progress = true; - else - afs_prioritise_error(_e, err, ac.abort_code); + old = rcu_dereference_protected(server->endpoint_state, + lockdep_is_held(&server->fs_lock)); + if (old) { + estate->responsive_set = old->responsive_set; + if (!new_alist) + new_alist = old->addresses; } - if (!in_progress) - afs_fs_probe_done(server); - return in_progress; -} + if (old_alist != new_alist) + afs_set_peer_appdata(server, old_alist, new_alist); + + estate->addresses = afs_get_addrlist(new_alist, afs_alist_trace_get_estate); + alist = estate->addresses; + estate->probe_seq = ++server->probe_counter; + atomic_set(&estate->nr_probing, alist->nr_addrs); + + if (new_alist) + server->addr_version = new_alist->version; + rcu_assign_pointer(server->endpoint_state, estate); + write_unlock(&server->fs_lock); + if (old) + set_bit(AFS_ESTATE_SUPERSEDED, &old->flags); + + trace_afs_estate(estate->server_id, estate->probe_seq, refcount_read(&estate->ref), + afs_estate_trace_alloc_probe); + + afs_get_address_preferences(net, new_alist); + + server->probed_at = jiffies; + unprobed = (1UL << alist->nr_addrs) - 1; + while (unprobed) { + unsigned int index = 0, i; + int best_prio = -1; + + for (i = 0; i < alist->nr_addrs; i++) { + if (test_bit(i, &unprobed) && + alist->addrs[i].prio > best_prio) { + index = i; + best_prio = alist->addrs[i].prio; + } + } + __clear_bit(index, &unprobed); -/* - * Send off probes to all unprobed servers. - */ -int afs_probe_fileservers(struct afs_net *net, struct key *key, - struct afs_server_list *list) -{ - struct afs_server *server; - struct afs_error e; - bool in_progress = false; - int i; - - e.error = 0; - e.responded = false; - for (i = 0; i < list->nr_servers; i++) { - server = list->servers[i].server; - if (test_bit(AFS_SERVER_FL_PROBED, &server->flags)) - continue; - - if (!test_and_set_bit_lock(AFS_SERVER_FL_PROBING, &server->flags) && - afs_do_probe_fileserver(net, server, key, i, &e)) - in_progress = true; + trace_afs_fs_probe(server, true, estate, index, 0, 0, 0); + if (!afs_fs_get_capabilities(net, server, estate, index, key)) + afs_fs_probe_not_done(net, server, estate, index); } - return in_progress ? 0 : e.error; + afs_put_endpoint_state(old, afs_estate_trace_put_probe); + afs_put_endpoint_state(estate, afs_estate_trace_put_probe); + return 0; } /* - * Wait for the first as-yet untried fileserver to respond. + * Wait for the first as-yet untried fileserver to respond, for the probe state + * to be superseded or for all probes to finish. */ -int afs_wait_for_fs_probes(struct afs_server_list *slist, unsigned long untried) +int afs_wait_for_fs_probes(struct afs_operation *op, struct afs_server_state *states, bool intr) { - struct wait_queue_entry *waits; - struct afs_server *server; - unsigned int rtt = UINT_MAX; - bool have_responders = false; - int pref = -1, i; + struct afs_endpoint_state *estate; + struct afs_server_list *slist = op->server_list; + bool still_probing = true; + int ret = 0, i; - _enter("%u,%lx", slist->nr_servers, untried); + _enter("%u", slist->nr_servers); - /* Only wait for servers that have a probe outstanding. */ for (i = 0; i < slist->nr_servers; i++) { - if (test_bit(i, &untried)) { - server = slist->servers[i].server; - if (!test_bit(AFS_SERVER_FL_PROBING, &server->flags)) - __clear_bit(i, &untried); - if (server->probe.responded) - have_responders = true; - } + estate = states[i].endpoint_state; + if (test_bit(AFS_ESTATE_SUPERSEDED, &estate->flags)) + return 2; + if (atomic_read(&estate->nr_probing)) + still_probing = true; + if (estate->responsive_set & states[i].untried_addrs) + return 1; } - if (have_responders || !untried) + if (!still_probing) return 0; - waits = kmalloc(array_size(slist->nr_servers, sizeof(*waits)), GFP_KERNEL); - if (!waits) - return -ENOMEM; - - for (i = 0; i < slist->nr_servers; i++) { - if (test_bit(i, &untried)) { - server = slist->servers[i].server; - init_waitqueue_entry(&waits[i], current); - add_wait_queue(&server->probe_wq, &waits[i]); - } - } + for (i = 0; i < slist->nr_servers; i++) + add_wait_queue(&slist->servers[i].server->probe_wq, &states[i].probe_waiter); for (;;) { - bool still_probing = false; + still_probing = false; - set_current_state(TASK_INTERRUPTIBLE); + set_current_state(intr ? TASK_INTERRUPTIBLE : TASK_UNINTERRUPTIBLE); for (i = 0; i < slist->nr_servers; i++) { - if (test_bit(i, &untried)) { - server = slist->servers[i].server; - if (server->probe.responded) - goto stop; - if (test_bit(AFS_SERVER_FL_PROBING, &server->flags)) - still_probing = true; + estate = states[i].endpoint_state; + if (test_bit(AFS_ESTATE_SUPERSEDED, &estate->flags)) { + ret = 2; + goto stop; + } + if (atomic_read(&estate->nr_probing)) + still_probing = true; + if (estate->responsive_set & states[i].untried_addrs) { + ret = 1; + goto stop; } } @@ -255,25 +361,179 @@ int afs_wait_for_fs_probes(struct afs_server_list *slist, unsigned long untried) stop: set_current_state(TASK_RUNNING); - for (i = 0; i < slist->nr_servers; i++) { - if (test_bit(i, &untried)) { - server = slist->servers[i].server; - if (server->probe.responded && - server->probe.rtt < rtt) { - pref = i; - rtt = server->probe.rtt; - } + for (i = 0; i < slist->nr_servers; i++) + remove_wait_queue(&slist->servers[i].server->probe_wq, &states[i].probe_waiter); + + if (!ret && signal_pending(current)) + ret = -ERESTARTSYS; + return ret; +} + +/* + * Probe timer. We have an increment on fs_outstanding that we need to pass + * along to the work item. + */ +void afs_fs_probe_timer(struct timer_list *timer) +{ + struct afs_net *net = container_of(timer, struct afs_net, fs_probe_timer); + + if (!net->live || !queue_work(afs_wq, &net->fs_prober)) + afs_dec_servers_outstanding(net); +} + +/* + * Dispatch a probe to a server. + */ +static void afs_dispatch_fs_probe(struct afs_net *net, struct afs_server *server) + __releases(&net->fs_lock) +{ + struct key *key = NULL; + + /* We remove it from the queues here - it will be added back to + * one of the queues on the completion of the probe. + */ + list_del_init(&server->probe_link); + + afs_get_server(server, afs_server_trace_get_probe); + write_sequnlock(&net->fs_lock); + + afs_fs_probe_fileserver(net, server, NULL, key); + afs_put_server(net, server, afs_server_trace_put_probe); +} + +/* + * Probe a server immediately without waiting for its due time to come + * round. This is used when all of the addresses have been tried. + */ +void afs_probe_fileserver(struct afs_net *net, struct afs_server *server) +{ + write_seqlock(&net->fs_lock); + if (!list_empty(&server->probe_link)) + return afs_dispatch_fs_probe(net, server); + write_sequnlock(&net->fs_lock); +} - remove_wait_queue(&server->probe_wq, &waits[i]); +/* + * Probe dispatcher to regularly dispatch probes to keep NAT alive. + */ +void afs_fs_probe_dispatcher(struct work_struct *work) +{ + struct afs_net *net = container_of(work, struct afs_net, fs_prober); + struct afs_server *fast, *slow, *server; + unsigned long nowj, timer_at, poll_at; + bool first_pass = true, set_timer = false; + + if (!net->live) { + afs_dec_servers_outstanding(net); + return; + } + + _enter(""); + + if (list_empty(&net->fs_probe_fast) && list_empty(&net->fs_probe_slow)) { + afs_dec_servers_outstanding(net); + _leave(" [none]"); + return; + } + +again: + write_seqlock(&net->fs_lock); + + fast = slow = server = NULL; + nowj = jiffies; + timer_at = nowj + MAX_JIFFY_OFFSET; + + if (!list_empty(&net->fs_probe_fast)) { + fast = list_first_entry(&net->fs_probe_fast, struct afs_server, probe_link); + poll_at = fast->probed_at + afs_fs_probe_fast_poll_interval; + if (time_before(nowj, poll_at)) { + timer_at = poll_at; + set_timer = true; + fast = NULL; + } + } + + if (!list_empty(&net->fs_probe_slow)) { + slow = list_first_entry(&net->fs_probe_slow, struct afs_server, probe_link); + poll_at = slow->probed_at + afs_fs_probe_slow_poll_interval; + if (time_before(nowj, poll_at)) { + if (time_before(poll_at, timer_at)) + timer_at = poll_at; + set_timer = true; + slow = NULL; } } - kfree(waits); + server = fast ?: slow; + if (server) + _debug("probe %pU", &server->uuid); + + if (server && (first_pass || !need_resched())) { + afs_dispatch_fs_probe(net, server); + first_pass = false; + goto again; + } + + write_sequnlock(&net->fs_lock); + + if (server) { + if (!queue_work(afs_wq, &net->fs_prober)) + afs_dec_servers_outstanding(net); + _leave(" [requeue]"); + } else if (set_timer) { + if (timer_reduce(&net->fs_probe_timer, timer_at)) + afs_dec_servers_outstanding(net); + _leave(" [timer]"); + } else { + afs_dec_servers_outstanding(net); + _leave(" [quiesce]"); + } +} - if (pref == -1 && signal_pending(current)) +/* + * Wait for a probe on a particular fileserver to complete for 2s. + */ +int afs_wait_for_one_fs_probe(struct afs_server *server, struct afs_endpoint_state *estate, + unsigned long exclude, bool is_intr) +{ + struct wait_queue_entry wait; + unsigned long timo = 2 * HZ; + + if (atomic_read(&estate->nr_probing) == 0) + goto dont_wait; + + init_wait_entry(&wait, 0); + for (;;) { + prepare_to_wait_event(&server->probe_wq, &wait, + is_intr ? TASK_INTERRUPTIBLE : TASK_UNINTERRUPTIBLE); + if (timo == 0 || + test_bit(AFS_ESTATE_SUPERSEDED, &estate->flags) || + (estate->responsive_set & ~exclude) || + atomic_read(&estate->nr_probing) == 0 || + (is_intr && signal_pending(current))) + break; + timo = schedule_timeout(timo); + } + + finish_wait(&server->probe_wq, &wait); + +dont_wait: + if (test_bit(AFS_ESTATE_SUPERSEDED, &estate->flags)) + return 0; + if (estate->responsive_set & ~exclude) + return 1; + if (is_intr && signal_pending(current)) return -ERESTARTSYS; + if (timo == 0) + return -ETIME; + return -EDESTADDRREQ; +} - if (pref >= 0) - slist->preferred = pref; - return 0; +/* + * Clean up the probing when the namespace is killed off. + */ +void afs_fs_probe_cleanup(struct afs_net *net) +{ + if (timer_delete_sync(&net->fs_probe_timer)) + afs_dec_servers_outstanding(net); } |
