From 6714d8e86bf443f6f7af50f9d432025649f091f5 Mon Sep 17 00:00:00 2001 From: Kurt Hackel Date: Thu, 15 Dec 2005 14:31:23 -0800 Subject: [PATCH] OCFS2: The Second Oracle Cluster Filesystem A distributed lock manager built with the cluster file system use case in mind. The OCFS2 dlm exposes a VMS style API, though things have been simplified internally. The only lock levels implemented currently are NLMODE, PRMODE and EXMODE. Signed-off-by: Mark Fasheh Signed-off-by: Kurt Hackel --- fs/ocfs2/dlm/dlmast.c | 466 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 466 insertions(+) create mode 100644 fs/ocfs2/dlm/dlmast.c (limited to 'fs/ocfs2/dlm/dlmast.c') diff --git a/fs/ocfs2/dlm/dlmast.c b/fs/ocfs2/dlm/dlmast.c new file mode 100644 index 00000000000..8d17d28ef91 --- /dev/null +++ b/fs/ocfs2/dlm/dlmast.c @@ -0,0 +1,466 @@ +/* -*- mode: c; c-basic-offset: 8; -*- + * vim: noexpandtab sw=8 ts=8 sts=0: + * + * dlmast.c + * + * AST and BAST functionality for local and remote nodes + * + * Copyright (C) 2004 Oracle. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public + * License along with this program; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + * + */ + + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + + +#include "cluster/heartbeat.h" +#include "cluster/nodemanager.h" +#include "cluster/tcp.h" +#include "cluster/endian.h" + +#include "dlmapi.h" +#include "dlmcommon.h" + +#define MLOG_MASK_PREFIX ML_DLM +#include "cluster/masklog.h" + +static void dlm_update_lvb(struct dlm_ctxt *dlm, struct dlm_lock_resource *res, + struct dlm_lock *lock); +static int dlm_should_cancel_bast(struct dlm_ctxt *dlm, struct dlm_lock *lock); + +/* Should be called as an ast gets queued to see if the new + * lock level will obsolete a pending bast. + * For example, if dlm_thread queued a bast for an EX lock that + * was blocking another EX, but before sending the bast the + * lock owner downconverted to NL, the bast is now obsolete. + * Only the ast should be sent. + * This is needed because the lock and convert paths can queue + * asts out-of-band (not waiting for dlm_thread) in order to + * allow for LKM_NOQUEUE to get immediate responses. */ +static int dlm_should_cancel_bast(struct dlm_ctxt *dlm, struct dlm_lock *lock) +{ + assert_spin_locked(&dlm->ast_lock); + assert_spin_locked(&lock->spinlock); + + if (lock->ml.highest_blocked == LKM_IVMODE) + return 0; + BUG_ON(lock->ml.highest_blocked == LKM_NLMODE); + + if (lock->bast_pending && + list_empty(&lock->bast_list)) + /* old bast already sent, ok */ + return 0; + + if (lock->ml.type == LKM_EXMODE) + /* EX blocks anything left, any bast still valid */ + return 0; + else if (lock->ml.type == LKM_NLMODE) + /* NL blocks nothing, no reason to send any bast, cancel it */ + return 1; + else if (lock->ml.highest_blocked != LKM_EXMODE) + /* PR only blocks EX */ + return 1; + + return 0; +} + +static void __dlm_queue_ast(struct dlm_ctxt *dlm, struct dlm_lock *lock) +{ + mlog_entry_void(); + + BUG_ON(!dlm); + BUG_ON(!lock); + + assert_spin_locked(&dlm->ast_lock); + if (!list_empty(&lock->ast_list)) { + mlog(ML_ERROR, "ast list not empty!! pending=%d, newlevel=%d\n", + lock->ast_pending, lock->ml.type); + BUG(); + } + BUG_ON(!list_empty(&lock->ast_list)); + if (lock->ast_pending) + mlog(0, "lock has an ast getting flushed right now\n"); + + /* putting lock on list, add a ref */ + dlm_lock_get(lock); + spin_lock(&lock->spinlock); + + /* check to see if this ast obsoletes the bast */ + if (dlm_should_cancel_bast(dlm, lock)) { + struct dlm_lock_resource *res = lock->lockres; + mlog(0, "%s: cancelling bast for %.*s\n", + dlm->name, res->lockname.len, res->lockname.name); + lock->bast_pending = 0; + list_del_init(&lock->bast_list); + lock->ml.highest_blocked = LKM_IVMODE; + /* removing lock from list, remove a ref. guaranteed + * this won't be the last ref because of the get above, + * so res->spinlock will not be taken here */ + dlm_lock_put(lock); + /* free up the reserved bast that we are cancelling. + * guaranteed that this will not be the last reserved + * ast because *both* an ast and a bast were reserved + * to get to this point. the res->spinlock will not be + * taken here */ + dlm_lockres_release_ast(dlm, res); + } + list_add_tail(&lock->ast_list, &dlm->pending_asts); + lock->ast_pending = 1; + spin_unlock(&lock->spinlock); +} + +void dlm_queue_ast(struct dlm_ctxt *dlm, struct dlm_lock *lock) +{ + mlog_entry_void(); + + BUG_ON(!dlm); + BUG_ON(!lock); + + spin_lock(&dlm->ast_lock); + __dlm_queue_ast(dlm, lock); + spin_unlock(&dlm->ast_lock); +} + + +static void __dlm_queue_bast(struct dlm_ctxt *dlm, struct dlm_lock *lock) +{ + mlog_entry_void(); + + BUG_ON(!dlm); + BUG_ON(!lock); + assert_spin_locked(&dlm->ast_lock); + + BUG_ON(!list_empty(&lock->bast_list)); + if (lock->bast_pending) + mlog(0, "lock has a bast getting flushed right now\n"); + + /* putting lock on list, add a ref */ + dlm_lock_get(lock); + spin_lock(&lock->spinlock); + list_add_tail(&lock->bast_list, &dlm->pending_basts); + lock->bast_pending = 1; + spin_unlock(&lock->spinlock); +} + +void dlm_queue_bast(struct dlm_ctxt *dlm, struct dlm_lock *lock) +{ + mlog_entry_void(); + + BUG_ON(!dlm); + BUG_ON(!lock); + + spin_lock(&dlm->ast_lock); + __dlm_queue_bast(dlm, lock); + spin_unlock(&dlm->ast_lock); +} + +static void dlm_update_lvb(struct dlm_ctxt *dlm, struct dlm_lock_resource *res, + struct dlm_lock *lock) +{ + struct dlm_lockstatus *lksb = lock->lksb; + BUG_ON(!lksb); + + /* only updates if this node masters the lockres */ + if (res->owner == dlm->node_num) { + + spin_lock(&res->spinlock); + /* check the lksb flags for the direction */ + if (lksb->flags & DLM_LKSB_GET_LVB) { + mlog(0, "getting lvb from lockres for %s node\n", + lock->ml.node == dlm->node_num ? "master" : + "remote"); + memcpy(lksb->lvb, res->lvb, DLM_LVB_LEN); + } else if (lksb->flags & DLM_LKSB_PUT_LVB) { + mlog(0, "setting lvb from lockres for %s node\n", + lock->ml.node == dlm->node_num ? "master" : + "remote"); + memcpy(res->lvb, lksb->lvb, DLM_LVB_LEN); + } + spin_unlock(&res->spinlock); + } + + /* reset any lvb flags on the lksb */ + lksb->flags &= ~(DLM_LKSB_PUT_LVB|DLM_LKSB_GET_LVB); +} + +void dlm_do_local_ast(struct dlm_ctxt *dlm, struct dlm_lock_resource *res, + struct dlm_lock *lock) +{ + dlm_astlockfunc_t *fn; + struct dlm_lockstatus *lksb; + + mlog_entry_void(); + + lksb = lock->lksb; + fn = lock->ast; + BUG_ON(lock->ml.node != dlm->node_num); + + dlm_update_lvb(dlm, res, lock); + (*fn)(lock->astdata); +} + + +int dlm_do_remote_ast(struct dlm_ctxt *dlm, struct dlm_lock_resource *res, + struct dlm_lock *lock) +{ + int ret; + struct dlm_lockstatus *lksb; + int lksbflags; + + mlog_entry_void(); + + lksb = lock->lksb; + BUG_ON(lock->ml.node == dlm->node_num); + + lksbflags = lksb->flags; + dlm_update_lvb(dlm, res, lock); + + /* lock request came from another node + * go do the ast over there */ + ret = dlm_send_proxy_ast(dlm, res, lock, lksbflags); + return ret; +} + +void dlm_do_local_bast(struct dlm_ctxt *dlm, struct dlm_lock_resource *res, + struct dlm_lock *lock, int blocked_type) +{ + dlm_bastlockfunc_t *fn = lock->bast; + + mlog_entry_void(); + BUG_ON(lock->ml.node != dlm->node_num); + + (*fn)(lock->astdata, blocked_type); +} + + + +int dlm_proxy_ast_handler(struct o2net_msg *msg, u32 len, void *data) +{ + int ret; + unsigned int locklen; + struct dlm_ctxt *dlm = data; + struct dlm_lock_resource *res = NULL; + struct dlm_lock *lock = NULL; + struct dlm_proxy_ast *past = (struct dlm_proxy_ast *) msg->buf; + char *name; + struct list_head *iter, *head=NULL; + u64 cookie; + u32 flags; + + if (!dlm_grab(dlm)) { + dlm_error(DLM_REJECTED); + return DLM_REJECTED; + } + + mlog_bug_on_msg(!dlm_domain_fully_joined(dlm), + "Domain %s not fully joined!\n", dlm->name); + + name = past->name; + locklen = past->namelen; + cookie = be64_to_cpu(past->cookie); + flags = be32_to_cpu(past->flags); + + if (locklen > DLM_LOCKID_NAME_MAX) { + ret = DLM_IVBUFLEN; + mlog(ML_ERROR, "Invalid name length in proxy ast handler!\n"); + goto leave; + } + + if ((flags & (LKM_PUT_LVB|LKM_GET_LVB)) == + (LKM_PUT_LVB|LKM_GET_LVB)) { + mlog(ML_ERROR, "both PUT and GET lvb specified\n"); + ret = DLM_BADARGS; + goto leave; + } + + mlog(0, "lvb: %s\n", flags & LKM_PUT_LVB ? "put lvb" : + (flags & LKM_GET_LVB ? "get lvb" : "none")); + + mlog(0, "type=%d, blocked_type=%d\n", past->type, past->blocked_type); + + if (past->type != DLM_AST && + past->type != DLM_BAST) { + mlog(ML_ERROR, "Unknown ast type! %d, cookie=%"MLFu64", " + "name=%.*s\n", past->type, cookie, locklen, name); + ret = DLM_IVLOCKID; + goto leave; + } + + res = dlm_lookup_lockres(dlm, name, locklen); + if (!res) { + mlog(ML_ERROR, "got %sast for unknown lockres! " + "cookie=%"MLFu64", name=%.*s, namelen=%u\n", + past->type == DLM_AST ? "" : "b", + cookie, locklen, name, locklen); + ret = DLM_IVLOCKID; + goto leave; + } + + /* cannot get a proxy ast message if this node owns it */ + BUG_ON(res->owner == dlm->node_num); + + mlog(0, "lockres %.*s\n", res->lockname.len, res->lockname.name); + + spin_lock(&res->spinlock); + if (res->state & DLM_LOCK_RES_RECOVERING) { + mlog(0, "responding with DLM_RECOVERING!\n"); + ret = DLM_RECOVERING; + goto unlock_out; + } + if (res->state & DLM_LOCK_RES_MIGRATING) { + mlog(0, "responding with DLM_MIGRATING!\n"); + ret = DLM_MIGRATING; + goto unlock_out; + } + /* try convert queue for both ast/bast */ + head = &res->converting; + lock = NULL; + list_for_each(iter, head) { + lock = list_entry (iter, struct dlm_lock, list); + if (be64_to_cpu(lock->ml.cookie) == cookie) + goto do_ast; + } + + /* if not on convert, try blocked for ast, granted for bast */ + if (past->type == DLM_AST) + head = &res->blocked; + else + head = &res->granted; + + list_for_each(iter, head) { + lock = list_entry (iter, struct dlm_lock, list); + if (be64_to_cpu(lock->ml.cookie) == cookie) + goto do_ast; + } + + mlog(ML_ERROR, "got %sast for unknown lock! cookie=%"MLFu64", " + "name=%.*s, namelen=%u\n", + past->type == DLM_AST ? "" : "b", cookie, locklen, name, locklen); + + ret = DLM_NORMAL; +unlock_out: + spin_unlock(&res->spinlock); + goto leave; + +do_ast: + ret = DLM_NORMAL; + if (past->type == DLM_AST) { + /* do not alter lock refcount. switching lists. */ + list_del_init(&lock->list); + list_add_tail(&lock->list, &res->granted); + mlog(0, "ast: adding to granted list... type=%d, " + "convert_type=%d\n", lock->ml.type, lock->ml.convert_type); + if (lock->ml.convert_type != LKM_IVMODE) { + lock->ml.type = lock->ml.convert_type; + lock->ml.convert_type = LKM_IVMODE; + } else { + // should already be there.... + } + + lock->lksb->status = DLM_NORMAL; + + /* if we requested the lvb, fetch it into our lksb now */ + if (flags & LKM_GET_LVB) { + BUG_ON(!(lock->lksb->flags & DLM_LKSB_GET_LVB)); + memcpy(lock->lksb->lvb, past->lvb, DLM_LVB_LEN); + } + } + spin_unlock(&res->spinlock); + + if (past->type == DLM_AST) + dlm_do_local_ast(dlm, res, lock); + else + dlm_do_local_bast(dlm, res, lock, past->blocked_type); + +leave: + + if (res) + dlm_lockres_put(res); + + dlm_put(dlm); + return ret; +} + + + +int dlm_send_proxy_ast_msg(struct dlm_ctxt *dlm, struct dlm_lock_resource *res, + struct dlm_lock *lock, int msg_type, + int blocked_type, int flags) +{ + int ret = 0; + struct dlm_proxy_ast past; + struct kvec vec[2]; + size_t veclen = 1; + int status; + + mlog_entry("res %.*s, to=%u, type=%d, blocked_type=%d\n", + res->lockname.len, res->lockname.name, lock->ml.node, + msg_type, blocked_type); + + memset(&past, 0, sizeof(struct dlm_proxy_ast)); + past.node_idx = dlm->node_num; + past.type = msg_type; + past.blocked_type = blocked_type; + past.namelen = res->lockname.len; + memcpy(past.name, res->lockname.name, past.namelen); + past.cookie = lock->ml.cookie; + + vec[0].iov_len = sizeof(struct dlm_proxy_ast); + vec[0].iov_base = &past; + if (flags & DLM_LKSB_GET_LVB) { + mlog(0, "returning requested LVB data\n"); + be32_add_cpu(&past.flags, LKM_GET_LVB); + vec[1].iov_len = DLM_LVB_LEN; + vec[1].iov_base = lock->lksb->lvb; + veclen++; + } + + ret = o2net_send_message_vec(DLM_PROXY_AST_MSG, dlm->key, vec, veclen, + lock->ml.node, &status); + if (ret < 0) + mlog_errno(ret); + else { + if (status == DLM_RECOVERING) { + mlog(ML_ERROR, "sent AST to node %u, it thinks this " + "node is dead!\n", lock->ml.node); + BUG(); + } else if (status == DLM_MIGRATING) { + mlog(ML_ERROR, "sent AST to node %u, it returned " + "DLM_MIGRATING!\n", lock->ml.node); + BUG(); + } else if (status != DLM_NORMAL) { + mlog(ML_ERROR, "AST to node %u returned %d!\n", + lock->ml.node, status); + /* ignore it */ + } + ret = 0; + } + return ret; +} -- cgit v1.2.3