diff options
Diffstat (limited to 'fs/dlm/requestqueue.c')
| -rw-r--r-- | fs/dlm/requestqueue.c | 171 |
1 files changed, 171 insertions, 0 deletions
diff --git a/fs/dlm/requestqueue.c b/fs/dlm/requestqueue.c new file mode 100644 index 000000000..1695f1b0d --- /dev/null +++ b/fs/dlm/requestqueue.c @@ -0,0 +1,171 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) 2005-2007 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +#include "dlm_internal.h" +#include "member.h" +#include "lock.h" +#include "dir.h" +#include "config.h" +#include "requestqueue.h" + +struct rq_entry { + struct list_head list; + uint32_t recover_seq; + int nodeid; + struct dlm_message request; +}; + +/* + * Requests received while the lockspace is in recovery get added to the + * request queue and processed when recovery is complete. This happens when + * the lockspace is suspended on some nodes before it is on others, or the + * lockspace is enabled on some while still suspended on others. + */ + +void dlm_add_requestqueue(struct dlm_ls *ls, int nodeid, struct dlm_message *ms) +{ + struct rq_entry *e; + int length = ms->m_header.h_length - sizeof(struct dlm_message); + + e = kmalloc(sizeof(struct rq_entry) + length, GFP_NOFS); + if (!e) { + log_print("dlm_add_requestqueue: out of memory len %d", length); + return; + } + + e->recover_seq = ls->ls_recover_seq & 0xFFFFFFFF; + e->nodeid = nodeid; + memcpy(&e->request, ms, ms->m_header.h_length); + + mutex_lock(&ls->ls_requestqueue_mutex); + list_add_tail(&e->list, &ls->ls_requestqueue); + mutex_unlock(&ls->ls_requestqueue_mutex); +} + +/* + * Called by dlm_recoverd to process normal messages saved while recovery was + * happening. Normal locking has been enabled before this is called. dlm_recv + * upon receiving a message, will wait for all saved messages to be drained + * here before processing the message it got. If a new dlm_ls_stop() arrives + * while we're processing these saved messages, it may block trying to suspend + * dlm_recv if dlm_recv is waiting for us in dlm_wait_requestqueue. In that + * case, we don't abort since locking_stopped is still 0. If dlm_recv is not + * waiting for us, then this processing may be aborted due to locking_stopped. + */ + +int dlm_process_requestqueue(struct dlm_ls *ls) +{ + struct rq_entry *e; + struct dlm_message *ms; + int error = 0; + + mutex_lock(&ls->ls_requestqueue_mutex); + + for (;;) { + if (list_empty(&ls->ls_requestqueue)) { + mutex_unlock(&ls->ls_requestqueue_mutex); + error = 0; + break; + } + e = list_entry(ls->ls_requestqueue.next, struct rq_entry, list); + mutex_unlock(&ls->ls_requestqueue_mutex); + + ms = &e->request; + + log_limit(ls, "dlm_process_requestqueue msg %d from %d " + "lkid %x remid %x result %d seq %u", + ms->m_type, ms->m_header.h_nodeid, + ms->m_lkid, ms->m_remid, ms->m_result, + e->recover_seq); + + dlm_receive_message_saved(ls, &e->request, e->recover_seq); + + mutex_lock(&ls->ls_requestqueue_mutex); + list_del(&e->list); + kfree(e); + + if (dlm_locking_stopped(ls)) { + log_debug(ls, "process_requestqueue abort running"); + mutex_unlock(&ls->ls_requestqueue_mutex); + error = -EINTR; + break; + } + schedule(); + } + + return error; +} + +/* + * After recovery is done, locking is resumed and dlm_recoverd takes all the + * saved requests and processes them as they would have been by dlm_recv. At + * the same time, dlm_recv will start receiving new requests from remote nodes. + * We want to delay dlm_recv processing new requests until dlm_recoverd has + * finished processing the old saved requests. We don't check for locking + * stopped here because dlm_ls_stop won't stop locking until it's suspended us + * (dlm_recv). + */ + +void dlm_wait_requestqueue(struct dlm_ls *ls) +{ + for (;;) { + mutex_lock(&ls->ls_requestqueue_mutex); + if (list_empty(&ls->ls_requestqueue)) + break; + mutex_unlock(&ls->ls_requestqueue_mutex); + schedule(); + } + mutex_unlock(&ls->ls_requestqueue_mutex); +} + +static int purge_request(struct dlm_ls *ls, struct dlm_message *ms, int nodeid) +{ + uint32_t type = ms->m_type; + + /* the ls is being cleaned up and freed by release_lockspace */ + if (!ls->ls_count) + return 1; + + if (dlm_is_removed(ls, nodeid)) + return 1; + + /* directory operations are always purged because the directory is + always rebuilt during recovery and the lookups resent */ + + if (type == DLM_MSG_REMOVE || + type == DLM_MSG_LOOKUP || + type == DLM_MSG_LOOKUP_REPLY) + return 1; + + if (!dlm_no_directory(ls)) + return 0; + + return 1; +} + +void dlm_purge_requestqueue(struct dlm_ls *ls) +{ + struct dlm_message *ms; + struct rq_entry *e, *safe; + + mutex_lock(&ls->ls_requestqueue_mutex); + list_for_each_entry_safe(e, safe, &ls->ls_requestqueue, list) { + ms = &e->request; + + if (purge_request(ls, ms, e->nodeid)) { + list_del(&e->list); + kfree(e); + } + } + mutex_unlock(&ls->ls_requestqueue_mutex); +} + |