diff options
Diffstat (limited to 'fs/ocfs2/dlm/dlmrecovery.c')
| -rw-r--r-- | fs/ocfs2/dlm/dlmrecovery.c | 2132 |
1 files changed, 2132 insertions, 0 deletions
diff --git a/fs/ocfs2/dlm/dlmrecovery.c b/fs/ocfs2/dlm/dlmrecovery.c new file mode 100644 index 000000000000..0c8eb1093f00 --- /dev/null +++ b/fs/ocfs2/dlm/dlmrecovery.c @@ -0,0 +1,2132 @@ +/* -*- mode: c; c-basic-offset: 8; -*- + * vim: noexpandtab sw=8 ts=8 sts=0: + * + * dlmrecovery.c + * + * recovery stuff + * + * 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 <linux/module.h> +#include <linux/fs.h> +#include <linux/types.h> +#include <linux/slab.h> +#include <linux/highmem.h> +#include <linux/utsname.h> +#include <linux/init.h> +#include <linux/sysctl.h> +#include <linux/random.h> +#include <linux/blkdev.h> +#include <linux/socket.h> +#include <linux/inet.h> +#include <linux/timer.h> +#include <linux/kthread.h> + + +#include "cluster/heartbeat.h" +#include "cluster/nodemanager.h" +#include "cluster/tcp.h" + +#include "dlmapi.h" +#include "dlmcommon.h" +#include "dlmdomain.h" + +#define MLOG_MASK_PREFIX (ML_DLM|ML_DLM_RECOVERY) +#include "cluster/masklog.h" + +static void dlm_do_local_recovery_cleanup(struct dlm_ctxt *dlm, u8 dead_node); + +static int dlm_recovery_thread(void *data); +void dlm_complete_recovery_thread(struct dlm_ctxt *dlm); +int dlm_launch_recovery_thread(struct dlm_ctxt *dlm); +static void dlm_kick_recovery_thread(struct dlm_ctxt *dlm); +static int dlm_do_recovery(struct dlm_ctxt *dlm); + +static int dlm_pick_recovery_master(struct dlm_ctxt *dlm); +static int dlm_remaster_locks(struct dlm_ctxt *dlm, u8 dead_node); +static int dlm_init_recovery_area(struct dlm_ctxt *dlm, u8 dead_node); +static int dlm_request_all_locks(struct dlm_ctxt *dlm, + u8 request_from, u8 dead_node); +static void dlm_destroy_recovery_area(struct dlm_ctxt *dlm, u8 dead_node); + +static inline int dlm_num_locks_in_lockres(struct dlm_lock_resource *res); +static void dlm_init_migratable_lockres(struct dlm_migratable_lockres *mres, + const char *lockname, int namelen, + int total_locks, u64 cookie, + u8 flags, u8 master); +static int dlm_send_mig_lockres_msg(struct dlm_ctxt *dlm, + struct dlm_migratable_lockres *mres, + u8 send_to, + struct dlm_lock_resource *res, + int total_locks); +static int dlm_lockres_master_requery(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + u8 *real_master); +static int dlm_process_recovery_data(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_migratable_lockres *mres); +static int dlm_do_master_requery(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + u8 nodenum, u8 *real_master); +static int dlm_send_finalize_reco_message(struct dlm_ctxt *dlm); +static int dlm_send_all_done_msg(struct dlm_ctxt *dlm, + u8 dead_node, u8 send_to); +static int dlm_send_begin_reco_message(struct dlm_ctxt *dlm, u8 dead_node); +static void dlm_move_reco_locks_to_list(struct dlm_ctxt *dlm, + struct list_head *list, u8 dead_node); +static void dlm_finish_local_lockres_recovery(struct dlm_ctxt *dlm, + u8 dead_node, u8 new_master); +static void dlm_reco_ast(void *astdata); +static void dlm_reco_bast(void *astdata, int blocked_type); +static void dlm_reco_unlock_ast(void *astdata, enum dlm_status st); +static void dlm_request_all_locks_worker(struct dlm_work_item *item, + void *data); +static void dlm_mig_lockres_worker(struct dlm_work_item *item, void *data); + +static u64 dlm_get_next_mig_cookie(void); + +static spinlock_t dlm_reco_state_lock = SPIN_LOCK_UNLOCKED; +static spinlock_t dlm_mig_cookie_lock = SPIN_LOCK_UNLOCKED; +static u64 dlm_mig_cookie = 1; + +static u64 dlm_get_next_mig_cookie(void) +{ + u64 c; + spin_lock(&dlm_mig_cookie_lock); + c = dlm_mig_cookie; + if (dlm_mig_cookie == (~0ULL)) + dlm_mig_cookie = 1; + else + dlm_mig_cookie++; + spin_unlock(&dlm_mig_cookie_lock); + return c; +} + +static inline void dlm_reset_recovery(struct dlm_ctxt *dlm) +{ + spin_lock(&dlm->spinlock); + clear_bit(dlm->reco.dead_node, dlm->recovery_map); + dlm->reco.dead_node = O2NM_INVALID_NODE_NUM; + dlm->reco.new_master = O2NM_INVALID_NODE_NUM; + spin_unlock(&dlm->spinlock); +} + +/* Worker function used during recovery. */ +void dlm_dispatch_work(void *data) +{ + struct dlm_ctxt *dlm = (struct dlm_ctxt *)data; + LIST_HEAD(tmp_list); + struct list_head *iter, *iter2; + struct dlm_work_item *item; + dlm_workfunc_t *workfunc; + + spin_lock(&dlm->work_lock); + list_splice_init(&dlm->work_list, &tmp_list); + spin_unlock(&dlm->work_lock); + + list_for_each_safe(iter, iter2, &tmp_list) { + item = list_entry(iter, struct dlm_work_item, list); + workfunc = item->func; + list_del_init(&item->list); + + /* already have ref on dlm to avoid having + * it disappear. just double-check. */ + BUG_ON(item->dlm != dlm); + + /* this is allowed to sleep and + * call network stuff */ + workfunc(item, item->data); + + dlm_put(dlm); + kfree(item); + } +} + +/* + * RECOVERY THREAD + */ + +static void dlm_kick_recovery_thread(struct dlm_ctxt *dlm) +{ + /* wake the recovery thread + * this will wake the reco thread in one of three places + * 1) sleeping with no recovery happening + * 2) sleeping with recovery mastered elsewhere + * 3) recovery mastered here, waiting on reco data */ + + wake_up(&dlm->dlm_reco_thread_wq); +} + +/* Launch the recovery thread */ +int dlm_launch_recovery_thread(struct dlm_ctxt *dlm) +{ + mlog(0, "starting dlm recovery thread...\n"); + + dlm->dlm_reco_thread_task = kthread_run(dlm_recovery_thread, dlm, + "dlm_reco_thread"); + if (IS_ERR(dlm->dlm_reco_thread_task)) { + mlog_errno(PTR_ERR(dlm->dlm_reco_thread_task)); + dlm->dlm_reco_thread_task = NULL; + return -EINVAL; + } + + return 0; +} + +void dlm_complete_recovery_thread(struct dlm_ctxt *dlm) +{ + if (dlm->dlm_reco_thread_task) { + mlog(0, "waiting for dlm recovery thread to exit\n"); + kthread_stop(dlm->dlm_reco_thread_task); + dlm->dlm_reco_thread_task = NULL; + } +} + + + +/* + * this is lame, but here's how recovery works... + * 1) all recovery threads cluster wide will work on recovering + * ONE node at a time + * 2) negotiate who will take over all the locks for the dead node. + * thats right... ALL the locks. + * 3) once a new master is chosen, everyone scans all locks + * and moves aside those mastered by the dead guy + * 4) each of these locks should be locked until recovery is done + * 5) the new master collects up all of secondary lock queue info + * one lock at a time, forcing each node to communicate back + * before continuing + * 6) each secondary lock queue responds with the full known lock info + * 7) once the new master has run all its locks, it sends a ALLDONE! + * message to everyone + * 8) upon receiving this message, the secondary queue node unlocks + * and responds to the ALLDONE + * 9) once the new master gets responses from everyone, he unlocks + * everything and recovery for this dead node is done + *10) go back to 2) while there are still dead nodes + * + */ + + +#define DLM_RECO_THREAD_TIMEOUT_MS (5 * 1000) + +static int dlm_recovery_thread(void *data) +{ + int status; + struct dlm_ctxt *dlm = data; + unsigned long timeout = msecs_to_jiffies(DLM_RECO_THREAD_TIMEOUT_MS); + + mlog(0, "dlm thread running for %s...\n", dlm->name); + + while (!kthread_should_stop()) { + if (dlm_joined(dlm)) { + status = dlm_do_recovery(dlm); + if (status == -EAGAIN) { + /* do not sleep, recheck immediately. */ + continue; + } + if (status < 0) + mlog_errno(status); + } + + wait_event_interruptible_timeout(dlm->dlm_reco_thread_wq, + kthread_should_stop(), + timeout); + } + + mlog(0, "quitting DLM recovery thread\n"); + return 0; +} + +/* callers of the top-level api calls (dlmlock/dlmunlock) should + * block on the dlm->reco.event when recovery is in progress. + * the dlm recovery thread will set this state when it begins + * recovering a dead node (as the new master or not) and clear + * the state and wake as soon as all affected lock resources have + * been marked with the RECOVERY flag */ +static int dlm_in_recovery(struct dlm_ctxt *dlm) +{ + int in_recovery; + spin_lock(&dlm->spinlock); + in_recovery = !!(dlm->reco.state & DLM_RECO_STATE_ACTIVE); + spin_unlock(&dlm->spinlock); + return in_recovery; +} + + +void dlm_wait_for_recovery(struct dlm_ctxt *dlm) +{ + wait_event(dlm->reco.event, !dlm_in_recovery(dlm)); +} + +static void dlm_begin_recovery(struct dlm_ctxt *dlm) +{ + spin_lock(&dlm->spinlock); + BUG_ON(dlm->reco.state & DLM_RECO_STATE_ACTIVE); + dlm->reco.state |= DLM_RECO_STATE_ACTIVE; + spin_unlock(&dlm->spinlock); +} + +static void dlm_end_recovery(struct dlm_ctxt *dlm) +{ + spin_lock(&dlm->spinlock); + BUG_ON(!(dlm->reco.state & DLM_RECO_STATE_ACTIVE)); + dlm->reco.state &= ~DLM_RECO_STATE_ACTIVE; + spin_unlock(&dlm->spinlock); + wake_up(&dlm->reco.event); +} + +static int dlm_do_recovery(struct dlm_ctxt *dlm) +{ + int status = 0; + + spin_lock(&dlm->spinlock); + + /* check to see if the new master has died */ + if (dlm->reco.new_master != O2NM_INVALID_NODE_NUM && + test_bit(dlm->reco.new_master, dlm->recovery_map)) { + mlog(0, "new master %u died while recovering %u!\n", + dlm->reco.new_master, dlm->reco.dead_node); + /* unset the new_master, leave dead_node */ + dlm->reco.new_master = O2NM_INVALID_NODE_NUM; + } + + /* select a target to recover */ + if (dlm->reco.dead_node == O2NM_INVALID_NODE_NUM) { + int bit; + + bit = find_next_bit (dlm->recovery_map, O2NM_MAX_NODES+1, 0); + if (bit >= O2NM_MAX_NODES || bit < 0) + dlm->reco.dead_node = O2NM_INVALID_NODE_NUM; + else + dlm->reco.dead_node = bit; + } else if (!test_bit(dlm->reco.dead_node, dlm->recovery_map)) { + /* BUG? */ + mlog(ML_ERROR, "dead_node %u no longer in recovery map!\n", + dlm->reco.dead_node); + dlm->reco.dead_node = O2NM_INVALID_NODE_NUM; + } + + if (dlm->reco.dead_node == O2NM_INVALID_NODE_NUM) { + // mlog(0, "nothing to recover! sleeping now!\n"); + spin_unlock(&dlm->spinlock); + /* return to main thread loop and sleep. */ + return 0; + } + mlog(0, "recovery thread found node %u in the recovery map!\n", + dlm->reco.dead_node); + spin_unlock(&dlm->spinlock); + + /* take write barrier */ + /* (stops the list reshuffling thread, proxy ast handling) */ + dlm_begin_recovery(dlm); + + if (dlm->reco.new_master == dlm->node_num) + goto master_here; + + if (dlm->reco.new_master == O2NM_INVALID_NODE_NUM) { + /* choose a new master */ + if (!dlm_pick_recovery_master(dlm)) { + /* already notified everyone. go. */ + dlm->reco.new_master = dlm->node_num; + goto master_here; + } + mlog(0, "another node will master this recovery session.\n"); + } + mlog(0, "dlm=%s, new_master=%u, this node=%u, dead_node=%u\n", + dlm->name, dlm->reco.new_master, + dlm->node_num, dlm->reco.dead_node); + + /* it is safe to start everything back up here + * because all of the dead node's lock resources + * have been marked as in-recovery */ + dlm_end_recovery(dlm); + + /* sleep out in main dlm_recovery_thread loop. */ + return 0; + +master_here: + mlog(0, "mastering recovery of %s:%u here(this=%u)!\n", + dlm->name, dlm->reco.dead_node, dlm->node_num); + + status = dlm_remaster_locks(dlm, dlm->reco.dead_node); + if (status < 0) { + mlog(ML_ERROR, "error %d remastering locks for node %u, " + "retrying.\n", status, dlm->reco.dead_node); + } else { + /* success! see if any other nodes need recovery */ + dlm_reset_recovery(dlm); + } + dlm_end_recovery(dlm); + + /* continue and look for another dead node */ + return -EAGAIN; +} + +static int dlm_remaster_locks(struct dlm_ctxt *dlm, u8 dead_node) +{ + int status = 0; + struct dlm_reco_node_data *ndata; + struct list_head *iter; + int all_nodes_done; + int destroy = 0; + int pass = 0; + + status = dlm_init_recovery_area(dlm, dead_node); + if (status < 0) + goto leave; + + /* safe to access the node data list without a lock, since this + * process is the only one to change the list */ + list_for_each(iter, &dlm->reco.node_data) { + ndata = list_entry (iter, struct dlm_reco_node_data, list); + BUG_ON(ndata->state != DLM_RECO_NODE_DATA_INIT); + ndata->state = DLM_RECO_NODE_DATA_REQUESTING; + + mlog(0, "requesting lock info from node %u\n", + ndata->node_num); + + if (ndata->node_num == dlm->node_num) { + ndata->state = DLM_RECO_NODE_DATA_DONE; + continue; + } + + status = dlm_request_all_locks(dlm, ndata->node_num, dead_node); + if (status < 0) { + mlog_errno(status); + if (dlm_is_host_down(status)) + ndata->state = DLM_RECO_NODE_DATA_DEAD; + else { + destroy = 1; + goto leave; + } + } + + switch (ndata->state) { + case DLM_RECO_NODE_DATA_INIT: + case DLM_RECO_NODE_DATA_FINALIZE_SENT: + case DLM_RECO_NODE_DATA_REQUESTED: + BUG(); + break; + case DLM_RECO_NODE_DATA_DEAD: + mlog(0, "node %u died after requesting " + "recovery info for node %u\n", + ndata->node_num, dead_node); + // start all over + destroy = 1; + status = -EAGAIN; + goto leave; + case DLM_RECO_NODE_DATA_REQUESTING: + ndata->state = DLM_RECO_NODE_DATA_REQUESTED; + mlog(0, "now receiving recovery data from " + "node %u for dead node %u\n", + ndata->node_num, dead_node); + break; + case DLM_RECO_NODE_DATA_RECEIVING: + mlog(0, "already receiving recovery data from " + "node %u for dead node %u\n", + ndata->node_num, dead_node); + break; + case DLM_RECO_NODE_DATA_DONE: + mlog(0, "already DONE receiving recovery data " + "from node %u for dead node %u\n", + ndata->node_num, dead_node); + break; + } + } + + mlog(0, "done requesting all lock info\n"); + + /* nodes should be sending reco data now + * just need to wait */ + + while (1) { + /* check all the nodes now to see if we are + * done, or if anyone died */ + all_nodes_done = 1; + spin_lock(&dlm_reco_state_lock); + list_for_each(iter, &dlm->reco.node_data) { + ndata = list_entry (iter, struct dlm_reco_node_data, list); + + mlog(0, "checking recovery state of node %u\n", + ndata->node_num); + switch (ndata->state) { + case DLM_RECO_NODE_DATA_INIT: + case DLM_RECO_NODE_DATA_REQUESTING: + mlog(ML_ERROR, "bad ndata state for " + "node %u: state=%d\n", + ndata->node_num, ndata->state); + BUG(); + break; + case DLM_RECO_NODE_DATA_DEAD: + mlog(0, "node %u died after " + "requesting recovery info for " + "node %u\n", ndata->node_num, + dead_node); + spin_unlock(&dlm_reco_state_lock); + // start all over + destroy = 1; + status = -EAGAIN; + goto leave; + case DLM_RECO_NODE_DATA_RECEIVING: + case DLM_RECO_NODE_DATA_REQUESTED: + all_nodes_done = 0; + break; + case DLM_RECO_NODE_DATA_DONE: + break; + case DLM_RECO_NODE_DATA_FINALIZE_SENT: + break; + } + } + spin_unlock(&dlm_reco_state_lock); + + mlog(0, "pass #%d, all_nodes_done?: %s\n", ++pass, + all_nodes_done?"yes":"no"); + if (all_nodes_done) { + int ret; + + /* all nodes are now in DLM_RECO_NODE_DATA_DONE state + * just send a finalize message to everyone and + * clean up */ + mlog(0, "all nodes are done! send finalize\n"); + ret = dlm_send_finalize_reco_message(dlm); + if (ret < 0) + mlog_errno(ret); + + spin_lock(&dlm->spinlock); + dlm_finish_local_lockres_recovery(dlm, dead_node, + dlm->node_num); + spin_unlock(&dlm->spinlock); + mlog(0, "should be done with recovery!\n"); + + mlog(0, "finishing recovery of %s at %lu, " + "dead=%u, this=%u, new=%u\n", dlm->name, + jiffies, dlm->reco.dead_node, + dlm->node_num, dlm->reco.new_master); + destroy = 1; + status = ret; + /* rescan everything marked dirty along the way */ + dlm_kick_thread(dlm, NULL); + break; + } + /* wait to be signalled, with periodic timeout + * to check for node death */ + wait_event_interruptible_timeout(dlm->dlm_reco_thread_wq, + kthread_should_stop(), + msecs_to_jiffies(DLM_RECO_THREAD_TIMEOUT_MS)); + + } + +leave: + if (destroy) + dlm_destroy_recovery_area(dlm, dead_node); + + mlog_exit(status); + return status; +} + +static int dlm_init_recovery_area(struct dlm_ctxt *dlm, u8 dead_node) +{ + int num=0; + struct dlm_reco_node_data *ndata; + + spin_lock(&dlm->spinlock); + memcpy(dlm->reco.node_map, dlm->domain_map, sizeof(dlm->domain_map)); + /* nodes can only be removed (by dying) after dropping + * this lock, and death will be trapped later, so this should do */ + spin_unlock(&dlm->spinlock); + + while (1) { + num = find_next_bit (dlm->reco.node_map, O2NM_MAX_NODES, num); + if (num >= O2NM_MAX_NODES) { + break; + } + BUG_ON(num == dead_node); + + ndata = kcalloc(1, sizeof(*ndata), GFP_KERNEL); + if (!ndata) { + dlm_destroy_recovery_area(dlm, dead_node); + return -ENOMEM; + } + ndata->node_num = num; + ndata->state = DLM_RECO_NODE_DATA_INIT; + spin_lock(&dlm_reco_state_lock); + list_add_tail(&ndata->list, &dlm->reco.node_data); + spin_unlock(&dlm_reco_state_lock); + num++; + } + + return 0; +} + +static void dlm_destroy_recovery_area(struct dlm_ctxt *dlm, u8 dead_node) +{ + struct list_head *iter, *iter2; + struct dlm_reco_node_data *ndata; + LIST_HEAD(tmplist); + + spin_lock(&dlm_reco_state_lock); + list_splice_init(&dlm->reco.node_data, &tmplist); + spin_unlock(&dlm_reco_state_lock); + + list_for_each_safe(iter, iter2, &tmplist) { + ndata = list_entry (iter, struct dlm_reco_node_data, list); + list_del_init(&ndata->list); + kfree(ndata); + } +} + +static int dlm_request_all_locks(struct dlm_ctxt *dlm, u8 request_from, + u8 dead_node) +{ + struct dlm_lock_request lr; + enum dlm_status ret; + + mlog(0, "\n"); + + + mlog(0, "dlm_request_all_locks: dead node is %u, sending request " + "to %u\n", dead_node, request_from); + + memset(&lr, 0, sizeof(lr)); + lr.node_idx = dlm->node_num; + lr.dead_node = dead_node; + + // send message + ret = DLM_NOLOCKMGR; + ret = o2net_send_message(DLM_LOCK_REQUEST_MSG, dlm->key, + &lr, sizeof(lr), request_from, NULL); + + /* negative status is handled by caller */ + if (ret < 0) + mlog_errno(ret); + + // return from here, then + // sleep until all received or error + return ret; + +} + +int dlm_request_all_locks_handler(struct o2net_msg *msg, u32 len, void *data) +{ + struct dlm_ctxt *dlm = data; + struct dlm_lock_request *lr = (struct dlm_lock_request *)msg->buf; + char *buf = NULL; + struct dlm_work_item *item = NULL; + + if (!dlm_grab(dlm)) + return -EINVAL; + + BUG_ON(lr->dead_node != dlm->reco.dead_node); + + item = kcalloc(1, sizeof(*item), GFP_KERNEL); + if (!item) { + dlm_put(dlm); + return -ENOMEM; + } + + /* this will get freed by dlm_request_all_locks_worker */ + buf = (char *) __get_free_page(GFP_KERNEL); + if (!buf) { + kfree(item); + dlm_put(dlm); + return -ENOMEM; + } + + /* queue up work for dlm_request_all_locks_worker */ + dlm_grab(dlm); /* get an extra ref for the work item */ + dlm_init_work_item(dlm, item, dlm_request_all_locks_worker, buf); + item->u.ral.reco_master = lr->node_idx; + item->u.ral.dead_node = lr->dead_node; + spin_lock(&dlm->work_lock); + list_add_tail(&item->list, &dlm->work_list); + spin_unlock(&dlm->work_lock); + schedule_work(&dlm->dispatched_work); + + dlm_put(dlm); + return 0; +} + +static void dlm_request_all_locks_worker(struct dlm_work_item *item, void *data) +{ + struct dlm_migratable_lockres *mres; + struct dlm_lock_resource *res; + struct dlm_ctxt *dlm; + LIST_HEAD(resources); + struct list_head *iter; + int ret; + u8 dead_node, reco_master; + + dlm = item->dlm; + dead_node = item->u.ral.dead_node; + reco_master = item->u.ral.reco_master; + BUG_ON(dead_node != dlm->reco.dead_node); + BUG_ON(reco_master != dlm->reco.new_master); + + mres = (struct dlm_migratable_lockres *)data; + + /* lock resources should have already been moved to the + * dlm->reco.resources list. now move items from that list + * to a temp list if the dead owner matches. note that the + * whole cluster recovers only one node at a time, so we + * can safely move UNKNOWN lock resources for each recovery + * session. */ + dlm_move_reco_locks_to_list(dlm, &resources, dead_node); + + /* now we can begin blasting lockreses without the dlm lock */ + list_for_each(iter, &resources) { + res = list_entry (iter, struct dlm_lock_resource, recovering); + ret = dlm_send_one_lockres(dlm, res, mres, reco_master, + DLM_MRES_RECOVERY); + if (ret < 0) + mlog_errno(ret); + } + + /* move the resources back to the list */ + spin_lock(&dlm->spinlock); + list_splice_init(&resources, &dlm->reco.resources); + spin_unlock(&dlm->spinlock); + + ret = dlm_send_all_done_msg(dlm, dead_node, reco_master); + if (ret < 0) + mlog_errno(ret); + + free_page((unsigned long)data); +} + + +static int dlm_send_all_done_msg(struct dlm_ctxt *dlm, u8 dead_node, u8 send_to) +{ + int ret, tmpret; + struct dlm_reco_data_done done_msg; + + memset(&done_msg, 0, sizeof(done_msg)); + done_msg.node_idx = dlm->node_num; + done_msg.dead_node = dead_node; + mlog(0, "sending DATA DONE message to %u, " + "my node=%u, dead node=%u\n", send_to, done_msg.node_idx, + done_msg.dead_node); + + ret = o2net_send_message(DLM_RECO_DATA_DONE_MSG, dlm->key, &done_msg, + sizeof(done_msg), send_to, &tmpret); + /* negative status is ignored by the caller */ + if (ret >= 0) + ret = tmpret; + return ret; +} + + +int dlm_reco_data_done_handler(struct o2net_msg *msg, u32 len, void *data) +{ + struct dlm_ctxt *dlm = data; + struct dlm_reco_data_done *done = (struct dlm_reco_data_done *)msg->buf; + struct list_head *iter; + struct dlm_reco_node_data *ndata = NULL; + int ret = -EINVAL; + + if (!dlm_grab(dlm)) + return -EINVAL; + + mlog(0, "got DATA DONE: dead_node=%u, reco.dead_node=%u, " + "node_idx=%u, this node=%u\n", done->dead_node, + dlm->reco.dead_node, done->node_idx, dlm->node_num); + BUG_ON(done->dead_node != dlm->reco.dead_node); + + spin_lock(&dlm_reco_state_lock); + list_for_each(iter, &dlm->reco.node_data) { + ndata = list_entry (iter, struct dlm_reco_node_data, list); + if (ndata->node_num != done->node_idx) + continue; + + switch (ndata->state) { + case DLM_RECO_NODE_DATA_INIT: + case DLM_RECO_NODE_DATA_DEAD: + case DLM_RECO_NODE_DATA_DONE: + case DLM_RECO_NODE_DATA_FINALIZE_SENT: + mlog(ML_ERROR, "bad ndata state for node %u:" + " state=%d\n", ndata->node_num, + ndata->state); + BUG(); + break; + case DLM_RECO_NODE_DATA_RECEIVING: + case DLM_RECO_NODE_DATA_REQUESTED: + case DLM_RECO_NODE_DATA_REQUESTING: + mlog(0, "node %u is DONE sending " + "recovery data!\n", + ndata->node_num); + + ndata->state = DLM_RECO_NODE_DATA_DONE; + ret = 0; + break; + } + } + spin_unlock(&dlm_reco_state_lock); + + /* wake the recovery thread, some node is done */ + if (!ret) + dlm_kick_recovery_thread(dlm); + + if (ret < 0) + mlog(ML_ERROR, "failed to find recovery node data for node " + "%u\n", done->node_idx); + dlm_put(dlm); + + mlog(0, "leaving reco data done handler, ret=%d\n", ret); + return ret; +} + +static void dlm_move_reco_locks_to_list(struct dlm_ctxt *dlm, + struct list_head *list, + u8 dead_node) +{ + struct dlm_lock_resource *res; + struct list_head *iter, *iter2; + + spin_lock(&dlm->spinlock); + list_for_each_safe(iter, iter2, &dlm->reco.resources) { + res = list_entry (iter, struct dlm_lock_resource, recovering); + if (dlm_is_recovery_lock(res->lockname.name, + res->lockname.len)) + continue; + if (res->owner == dead_node) { + mlog(0, "found lockres owned by dead node while " + "doing recovery for node %u. sending it.\n", + dead_node); + list_del_init(&res->recovering); + list_add_tail(&res->recovering, list); + } else if (res->owner == DLM_LOCK_RES_OWNER_UNKNOWN) { + mlog(0, "found UNKNOWN owner while doing recovery " + "for node %u. sending it.\n", dead_node); + list_del_init(&res->recovering); + list_add_tail(&res->recovering, list); + } + } + spin_unlock(&dlm->spinlock); +} + +static inline int dlm_num_locks_in_lockres(struct dlm_lock_resource *res) +{ + int total_locks = 0; + struct list_head *iter, *queue = &res->granted; + int i; + + for (i=0; i<3; i++) { + list_for_each(iter, queue) + total_locks++; + queue++; + } + return total_locks; +} + + +static int dlm_send_mig_lockres_msg(struct dlm_ctxt *dlm, + struct dlm_migratable_lockres *mres, + u8 send_to, + struct dlm_lock_resource *res, + int total_locks) +{ + u64 mig_cookie = be64_to_cpu(mres->mig_cookie); + int mres_total_locks = be32_to_cpu(mres->total_locks); + int sz, ret = 0, status = 0; + u8 orig_flags = mres->flags, + orig_master = mres->master; + + BUG_ON(mres->num_locks > DLM_MAX_MIGRATABLE_LOCKS); + if (!mres->num_locks) + return 0; + + sz = sizeof(struct dlm_migratable_lockres) + + (mres->num_locks * sizeof(struct dlm_migratable_lock)); + + /* add an all-done flag if we reached the last lock */ + orig_flags = mres->flags; + BUG_ON(total_locks > mres_total_locks); + if (total_locks == mres_total_locks) + mres->flags |= DLM_MRES_ALL_DONE; + + /* send it */ + ret = o2net_send_message(DLM_MIG_LOCKRES_MSG, dlm->key, mres, + sz, send_to, &status); + if (ret < 0) { + /* XXX: negative status is not handled. + * this will end up killing this node. */ + mlog_errno(ret); + } else { + /* might get an -ENOMEM back here */ + ret = status; + if (ret < 0) { + mlog_errno(ret); + + if (ret == -EFAULT) { + mlog(ML_ERROR, "node %u told me to kill " + "myself!\n", send_to); + BUG(); + } + } + } + + /* zero and reinit the message buffer */ + dlm_init_migratable_lockres(mres, res->lockname.name, + res->lockname.len, mres_total_locks, + mig_cookie, orig_flags, orig_master); + return ret; +} + +static void dlm_init_migratable_lockres(struct dlm_migratable_lockres *mres, + const char *lockname, int namelen, + int total_locks, u64 cookie, + u8 flags, u8 master) +{ + /* mres here is one full page */ + memset(mres, 0, PAGE_SIZE); + mres->lockname_len = namelen; + memcpy(mres->lockname, lockname, namelen); + mres->num_locks = 0; + mres->total_locks = cpu_to_be32(total_locks); + mres->mig_cookie = cpu_to_be64(cookie); + mres->flags = flags; + mres->master = master; +} + + +/* returns 1 if this lock fills the network structure, + * 0 otherwise */ +static int dlm_add_lock_to_array(struct dlm_lock *lock, + struct dlm_migratable_lockres *mres, int queue) +{ + struct dlm_migratable_lock *ml; + int lock_num = mres->num_locks; + + ml = &(mres->ml[lock_num]); + ml->cookie = lock->ml.cookie; + ml->type = lock->ml.type; + ml->convert_type = lock->ml.convert_type; + ml->highest_blocked = lock->ml.highest_blocked; + ml->list = queue; + if (lock->lksb) { + ml->flags = lock->lksb->flags; + /* send our current lvb */ + if (ml->type == LKM_EXMODE || + ml->type == LKM_PRMODE) { + /* if it is already set, this had better be a PR + * and it has to match */ + if (mres->lvb[0] && (ml->type == LKM_EXMODE || + memcmp(mres->lvb, lock->lksb->lvb, DLM_LVB_LEN))) { + mlog(ML_ERROR, "mismatched lvbs!\n"); + __dlm_print_one_lock_resource(lock->lockres); + BUG(); + } + memcpy(mres->lvb, lock->lksb->lvb, DLM_LVB_LEN); + } + } + ml->node = lock->ml.node; + mres->num_locks++; + /* we reached the max, send this network message */ + if (mres->num_locks == DLM_MAX_MIGRATABLE_LOCKS) + return 1; + return 0; +} + + +int dlm_send_one_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res, + struct dlm_migratable_lockres *mres, + u8 send_to, u8 flags) +{ + struct list_head *queue, *iter; + int total_locks, i; + u64 mig_cookie = 0; + struct dlm_lock *lock; + int ret = 0; + + BUG_ON(!(flags & (DLM_MRES_RECOVERY|DLM_MRES_MIGRATION))); + + mlog(0, "sending to %u\n", send_to); + + total_locks = dlm_num_locks_in_lockres(res); + if (total_locks > DLM_MAX_MIGRATABLE_LOCKS) { + /* rare, but possible */ + mlog(0, "argh. lockres has %d locks. this will " + "require more than one network packet to " + "migrate\n", total_locks); + mig_cookie = dlm_get_next_mig_cookie(); + } + + dlm_init_migratable_lockres(mres, res->lockname.name, + res->lockname.len, total_locks, + mig_cookie, flags, res->owner); + + total_locks = 0; + for (i=DLM_GRANTED_LIST; i<=DLM_BLOCKED_LIST; i++) { + queue = dlm_list_idx_to_ptr(res, i); + list_for_each(iter, queue) { + lock = list_entry (iter, struct dlm_lock, list); + + /* add another lock. */ + total_locks++; + if (!dlm_add_lock_to_array(lock, mres, i)) + continue; + + /* this filled the lock message, + * we must send it immediately. */ + ret = dlm_send_mig_lockres_msg(dlm, mres, send_to, + res, total_locks); + if (ret < 0) { + // TODO + mlog(ML_ERROR, "dlm_send_mig_lockres_msg " + "returned %d, TODO\n", ret); + BUG(); + } + } + } + /* flush any remaining locks */ + ret = dlm_send_mig_lockres_msg(dlm, mres, send_to, res, total_locks); + if (ret < 0) { + // TODO + mlog(ML_ERROR, "dlm_send_mig_lockres_msg returned %d, " + "TODO\n", ret); + BUG(); + } + return ret; +} + + + +/* + * this message will contain no more than one page worth of + * recovery data, and it will work on only one lockres. + * there may be many locks in this page, and we may need to wait + * for additional packets to complete all the locks (rare, but + * possible). + */ +/* + * NOTE: the allocation error cases here are scary + * we really cannot afford to fail an alloc in recovery + * do we spin? returning an error only delays the problem really + */ + +int dlm_mig_lockres_handler(struct o2net_msg *msg, u32 len, void *data) +{ + struct dlm_ctxt *dlm = data; + struct dlm_migratable_lockres *mres = + (struct dlm_migratable_lockres *)msg->buf; + int ret = 0; + u8 real_master; + char *buf = NULL; + struct dlm_work_item *item = NULL; + struct dlm_lock_resource *res = NULL; + + if (!dlm_grab(dlm)) + return -EINVAL; + + BUG_ON(!(mres->flags & (DLM_MRES_RECOVERY|DLM_MRES_MIGRATION))); + + real_master = mres->master; + if (real_master == DLM_LOCK_RES_OWNER_UNKNOWN) { + /* cannot migrate a lockres with no master */ + BUG_ON(!(mres->flags & DLM_MRES_RECOVERY)); + } + + mlog(0, "%s message received from node %u\n", + (mres->flags & DLM_MRES_RECOVERY) ? + "recovery" : "migration", mres->master); + if (mres->flags & DLM_MRES_ALL_DONE) + mlog(0, "all done flag. all lockres data received!\n"); + + ret = -ENOMEM; + buf = kmalloc(be16_to_cpu(msg->data_len), GFP_KERNEL); + item = kcalloc(1, sizeof(*item), GFP_KERNEL); + if (!buf || !item) + goto leave; + + /* lookup the lock to see if we have a secondary queue for this + * already... just add the locks in and this will have its owner + * and RECOVERY flag changed when it completes. */ + res = dlm_lookup_lockres(dlm, mres->lockname, mres->lockname_len); + if (res) { + /* this will get a ref on res */ + /* mark it as recovering/migrating and hash it */ + spin_lock(&res->spinlock); + if (mres->flags & DLM_MRES_RECOVERY) { + res->state |= DLM_LOCK_RES_RECOVERING; + } else { + if (res->state & DLM_LOCK_RES_MIGRATING) { + /* this is at least the second + * lockres message */ + mlog(0, "lock %.*s is already migrating\n", + mres->lockname_len, + mres->lockname); + } else if (res->state & DLM_LOCK_RES_RECOVERING) { + /* caller should BUG */ + mlog(ML_ERROR, "node is attempting to migrate " + "lock %.*s, but marked as recovering!\n", + mres->lockname_len, mres->lockname); + ret = -EFAULT; + spin_unlock(&res->spinlock); + goto leave; + } + res->state |= DLM_LOCK_RES_MIGRATING; + } + spin_unlock(&res->spinlock); + } else { + /* need to allocate, just like if it was + * mastered here normally */ + res = dlm_new_lockres(dlm, mres->lockname, mres->lockname_len); + if (!res) + goto leave; + + /* to match the ref that we would have gotten if + * dlm_lookup_lockres had succeeded */ + dlm_lockres_get(res); + + /* mark it as recovering/migrating and hash it */ + if (mres->flags & DLM_MRES_RECOVERY) + res->state |= DLM_LOCK_RES_RECOVERING; + else + res->state |= DLM_LOCK_RES_MIGRATING; + + spin_lock(&dlm->spinlock); + __dlm_insert_lockres(dlm, res); + spin_unlock(&dlm->spinlock); + + /* now that the new lockres is inserted, + * make it usable by other processes */ + spin_lock(&res->spinlock); + res->state &= ~DLM_LOCK_RES_IN_PROGRESS; + spin_unlock(&res->spinlock); + + /* add an extra ref for just-allocated lockres + * otherwise the lockres will be purged immediately */ + dlm_lockres_get(res); + + } + + /* at this point we have allocated everything we need, + * and we have a hashed lockres with an extra ref and + * the proper res->state flags. */ + ret = 0; + if (mres->master == DLM_LOCK_RES_OWNER_UNKNOWN) { + /* migration cannot have an unknown master */ + BUG_ON(!(mres->flags & DLM_MRES_RECOVERY)); + mlog(0, "recovery has passed me a lockres with an " + "unknown owner.. will need to requery: " + "%.*s\n", mres->lockname_len, mres->lockname); + } else { + spin_lock(&res->spinlock); + dlm_change_lockres_owner(dlm, res, dlm->node_num); + spin_unlock(&res->spinlock); + } + + /* queue up work for dlm_mig_lockres_worker */ + dlm_grab(dlm); /* get an extra ref for the work item */ + memcpy(buf, msg->buf, be16_to_cpu(msg->data_len)); /* copy the whole message */ + dlm_init_work_item(dlm, item, dlm_mig_lockres_worker, buf); + item->u.ml.lockres = res; /* already have a ref */ + item->u.ml.real_master = real_master; + spin_lock(&dlm->work_lock); + list_add_tail(&item->list, &dlm->work_list); + spin_unlock(&dlm->work_lock); + schedule_work(&dlm->dispatched_work); + +leave: + dlm_put(dlm); + if (ret < 0) { + if (buf) + kfree(buf); + if (item) + kfree(item); + } + + mlog_exit(ret); + return ret; +} + + +static void dlm_mig_lockres_worker(struct dlm_work_item *item, void *data) +{ + struct dlm_ctxt *dlm = data; + struct dlm_migratable_lockres *mres; + int ret = 0; + struct dlm_lock_resource *res; + u8 real_master; + + dlm = item->dlm; + mres = (struct dlm_migratable_lockres *)data; + + res = item->u.ml.lockres; + real_master = item->u.ml.real_master; + + if (real_master == DLM_LOCK_RES_OWNER_UNKNOWN) { + /* this case is super-rare. only occurs if + * node death happens during migration. */ +again: + ret = dlm_lockres_master_requery(dlm, res, &real_master); + if (ret < 0) { + mlog(0, "dlm_lockres_master_requery failure: %d\n", + ret); + goto again; + } + if (real_master == DLM_LOCK_RES_OWNER_UNKNOWN) { + mlog(0, "lockres %.*s not claimed. " + "this node will take it.\n", + res->lockname.len, res->lockname.name); + } else { + mlog(0, "master needs to respond to sender " + "that node %u still owns %.*s\n", + real_master, res->lockname.len, + res->lockname.name); + /* cannot touch this lockres */ + goto leave; + } + } + + ret = dlm_process_recovery_data(dlm, res, mres); + if (ret < 0) + mlog(0, "dlm_process_recovery_data returned %d\n", ret); + else + mlog(0, "dlm_process_recovery_data succeeded\n"); + + if ((mres->flags & (DLM_MRES_MIGRATION|DLM_MRES_ALL_DONE)) == + (DLM_MRES_MIGRATION|DLM_MRES_ALL_DONE)) { + ret = dlm_finish_migration(dlm, res, mres->master); + if (ret < 0) + mlog_errno(ret); + } + +leave: + kfree(data); + mlog_exit(ret); +} + + + +static int dlm_lockres_master_requery(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + u8 *real_master) +{ + struct dlm_node_iter iter; + int nodenum; + int ret = 0; + + *real_master = DLM_LOCK_RES_OWNER_UNKNOWN; + + /* we only reach here if one of the two nodes in a + * migration died while the migration was in progress. + * at this point we need to requery the master. we + * know that the new_master got as far as creating + * an mle on at least one node, but we do not know + * if any nodes had actually cleared the mle and set + * the master to the new_master. the old master + * is supposed to set the owner to UNKNOWN in the + * event of a new_master death, so the only possible + * responses that we can get from nodes here are + * that the master is new_master, or that the master + * is UNKNOWN. + * if all nodes come back with UNKNOWN then we know + * the lock needs remastering here. + * if any node comes back with a valid master, check + * to see if that master is the one that we are + * recovering. if so, then the new_master died and + * we need to remaster this lock. if not, then the + * new_master survived and that node will respond to + * other nodes about the owner. + * if there is an owner, this node needs to dump this + * lockres and alert the sender that this lockres + * was rejected. */ + spin_lock(&dlm->spinlock); + dlm_node_iter_init(dlm->domain_map, &iter); + spin_unlock(&dlm->spinlock); + + while ((nodenum = dlm_node_iter_next(&iter)) >= 0) { + /* do not send to self */ + if (nodenum == dlm->node_num) + continue; + ret = dlm_do_master_requery(dlm, res, nodenum, real_master); + if (ret < 0) { + mlog_errno(ret); + BUG(); + /* TODO: need to figure a way to restart this */ + } + if (*real_master != DLM_LOCK_RES_OWNER_UNKNOWN) { + mlog(0, "lock master is %u\n", *real_master); + break; + } + } + return ret; +} + + +static int dlm_do_master_requery(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + u8 nodenum, u8 *real_master) +{ + int ret = -EINVAL; + struct dlm_master_requery req; + int status = DLM_LOCK_RES_OWNER_UNKNOWN; + + memset(&req, 0, sizeof(req)); + req.node_idx = dlm->node_num; + req.namelen = res->lockname.len; + memcpy(req.name, res->lockname.name, res->lockname.len); + + ret = o2net_send_message(DLM_MASTER_REQUERY_MSG, dlm->key, + &req, sizeof(req), nodenum, &status); + /* XXX: negative status not handled properly here. */ + if (ret < 0) + mlog_errno(ret); + else { + BUG_ON(status < 0); + BUG_ON(status > DLM_LOCK_RES_OWNER_UNKNOWN); + *real_master = (u8) (status & 0xff); + mlog(0, "node %u responded to master requery with %u\n", + nodenum, *real_master); + ret = 0; + } + return ret; +} + + +/* this function cannot error, so unless the sending + * or receiving of the message failed, the owner can + * be trusted */ +int dlm_master_requery_handler(struct o2net_msg *msg, u32 len, void *data) +{ + struct dlm_ctxt *dlm = data; + struct dlm_master_requery *req = (struct dlm_master_requery *)msg->buf; + struct dlm_lock_resource *res = NULL; + int master = DLM_LOCK_RES_OWNER_UNKNOWN; + u32 flags = DLM_ASSERT_MASTER_REQUERY; + + if (!dlm_grab(dlm)) { + /* since the domain has gone away on this + * node, the proper response is UNKNOWN */ + return master; + } + + spin_lock(&dlm->spinlock); + res = __dlm_lookup_lockres(dlm, req->name, req->namelen); + if (res) { + spin_lock(&res->spinlock); + master = res->owner; + if (master == dlm->node_num) { + int ret = dlm_dispatch_assert_master(dlm, res, + 0, 0, flags); + if (ret < 0) { + mlog_errno(-ENOMEM); + /* retry!? */ + BUG(); + } + } + spin_unlock(&res->spinlock); + } + spin_unlock(&dlm->spinlock); + + dlm_put(dlm); + return master; +} + +static inline struct list_head * +dlm_list_num_to_pointer(struct dlm_lock_resource *res, int list_num) +{ + struct list_head *ret; + BUG_ON(list_num < 0); + BUG_ON(list_num > 2); + ret = &(res->granted); + ret += list_num; + return ret; +} +/* TODO: do ast flush business + * TODO: do MIGRATING and RECOVERING spinning + */ + +/* +* NOTE about in-flight requests during migration: +* +* Before attempting the migrate, the master has marked the lockres as +* MIGRATING and then flushed all of its pending ASTS. So any in-flight +* requests either got queued before the MIGRATING flag got set, in which +* case the lock data will reflect the change and a return message is on +* the way, or the request failed to get in before MIGRATING got set. In +* this case, the caller will be told to spin and wait for the MIGRATING +* flag to be dropped, then recheck the master. +* This holds true for the convert, cancel and unlock cases, and since lvb +* updates are tied to these same messages, it applies to lvb updates as +* well. For the lock case, there is no way a lock can be on the master +* queue and not be on the secondary queue since the lock is always added +* locally first. This means that the new target node will never be sent +* a lock that he doesn't already have on the list. +* In total, this means that the local lock is correct and should not be +* updated to match the one sent by the master. Any messages sent back +* from the master before the MIGRATING flag will bring the lock properly +* up-to-date, and the change will be ordered properly for the waiter. +* We will *not* attempt to modify the lock underneath the waiter. +*/ + +static int dlm_process_recovery_data(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, + struct dlm_migratable_lockres *mres) +{ + struct dlm_migratable_lock *ml; + struct list_head *queue; + struct dlm_lock *newlock = NULL; + struct dlm_lockstatus *lksb = NULL; + int ret = 0; + int i; + struct list_head *iter; + struct dlm_lock *lock = NULL; + + mlog(0, "running %d locks for this lockres\n", mres->num_locks); + for (i=0; i<mres->num_locks; i++) { + ml = &(mres->ml[i]); + BUG_ON(ml->highest_blocked != LKM_IVMODE); + newlock = NULL; + lksb = NULL; + + queue = dlm_list_num_to_pointer(res, ml->list); + + /* if the lock is for the local node it needs to + * be moved to the proper location within the queue. + * do not allocate a new lock structure. */ + if (ml->node == dlm->node_num) { + /* MIGRATION ONLY! */ + BUG_ON(!(mres->flags & DLM_MRES_MIGRATION)); + + spin_lock(&res->spinlock); + list_for_each(iter, queue) { + lock = list_entry (iter, struct dlm_lock, list); + if (lock->ml.cookie != ml->cookie) + lock = NULL; + else + break; + } + + /* lock is always created locally first, and + * destroyed locally last. it must be on the list */ + if (!lock) { + mlog(ML_ERROR, "could not find local lock " + "with cookie %"MLFu64"!\n", + ml->cookie); + BUG(); + } + BUG_ON(lock->ml.node != ml->node); + + /* see NOTE above about why we do not update + * to match the master here */ + + /* move the lock to its proper place */ + /* do not alter lock refcount. switching lists. */ + list_del_init(&lock->list); + list_add_tail(&lock->list, queue); + spin_unlock(&res->spinlock); + + mlog(0, "just reordered a local lock!\n"); + continue; + } + + /* lock is for another node. */ + newlock = dlm_new_lock(ml->type, ml->node, + be64_to_cpu(ml->cookie), NULL); + if (!newlock) { + ret = -ENOMEM; + goto leave; + } + lksb = newlock->lksb; + dlm_lock_attach_lockres(newlock, res); + + if (ml->convert_type != LKM_IVMODE) { + BUG_ON(queue != &res->converting); + newlock->ml.convert_type = ml->convert_type; + } + lksb->flags |= (ml->flags & + (DLM_LKSB_PUT_LVB|DLM_LKSB_GET_LVB)); + + if (mres->lvb[0]) { + if (lksb->flags & DLM_LKSB_PUT_LVB) { + /* other node was trying to update + * lvb when node died. recreate the + * lksb with the updated lvb. */ + memcpy(lksb->lvb, mres->lvb, DLM_LVB_LEN); + } else { + /* otherwise, the node is sending its + * most recent valid lvb info */ + BUG_ON(ml->type != LKM_EXMODE && + ml->type != LKM_PRMODE); + if (res->lvb[0] && (ml->type == LKM_EXMODE || + memcmp(res->lvb, mres->lvb, DLM_LVB_LEN))) { + mlog(ML_ERROR, "received bad lvb!\n"); + __dlm_print_one_lock_resource(res); + BUG(); + } + memcpy(res->lvb, mres->lvb, DLM_LVB_LEN); + } + } + + + /* NOTE: + * wrt lock queue ordering and recovery: + * 1. order of locks on granted queue is + * meaningless. + * 2. order of locks on converting queue is + * LOST with the node death. sorry charlie. + * 3. order of locks on the blocked queue is + * also LOST. + * order of locks does not affect integrity, it + * just means that a lock request may get pushed + * back in line as a result of the node death. + * also note that for a given node the lock order + * for its secondary queue locks is preserved + * relative to each other, but clearly *not* + * preserved relative to locks from other nodes. + */ + spin_lock(&res->spinlock); + dlm_lock_get(newlock); + list_add_tail(&newlock->list, queue); + spin_unlock(&res->spinlock); + } + mlog(0, "done running all the locks\n"); + +leave: + if (ret < 0) { + mlog_errno(ret); + if (newlock) + dlm_lock_put(newlock); + } + + mlog_exit(ret); + return ret; +} + +void dlm_move_lockres_to_recovery_list(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res) +{ + int i; + struct list_head *queue, *iter, *iter2; + struct dlm_lock *lock; + + res->state |= DLM_LOCK_RES_RECOVERING; + if (!list_empty(&res->recovering)) + list_del_init(&res->recovering); + list_add_tail(&res->recovering, &dlm->reco.resources); + + /* find any pending locks and put them back on proper list */ + for (i=DLM_BLOCKED_LIST; i>=DLM_GRANTED_LIST; i--) { + queue = dlm_list_idx_to_ptr(res, i); + list_for_each_safe(iter, iter2, queue) { + lock = list_entry (iter, struct dlm_lock, list); + dlm_lock_get(lock); + if (lock->convert_pending) { + /* move converting lock back to granted */ + BUG_ON(i != DLM_CONVERTING_LIST); + mlog(0, "node died with convert pending " + "on %.*s. move back to granted list.\n", + res->lockname.len, res->lockname.name); + dlm_revert_pending_convert(res, lock); + lock->convert_pending = 0; + } else if (lock->lock_pending) { + /* remove pending lock requests completely */ + BUG_ON(i != DLM_BLOCKED_LIST); + mlog(0, "node died with lock pending " + "on %.*s. remove from blocked list and skip.\n", + res->lockname.len, res->lockname.name); + /* lock will be floating until ref in + * dlmlock_remote is freed after the network + * call returns. ok for it to not be on any + * list since no ast can be called + * (the master is dead). */ + dlm_revert_pending_lock(res, lock); + lock->lock_pending = 0; + } else if (lock->unlock_pending) { + /* if an unlock was in progress, treat as + * if this had completed successfully + * before sending this lock state to the + * new master. note that the dlm_unlock + * call is still responsible for calling + * the unlockast. that will happen after + * the network call times out. for now, + * just move lists to prepare the new + * recovery master. */ + BUG_ON(i != DLM_GRANTED_LIST); + mlog(0, "node died with unlock pending " + "on %.*s. remove from blocked list and skip.\n", + res->lockname.len, res->lockname.name); + dlm_commit_pending_unlock(res, lock); + lock->unlock_pending = 0; + } else if (lock->cancel_pending) { + /* if a cancel was in progress, treat as + * if this had completed successfully + * before sending this lock state to the + * new master */ + BUG_ON(i != DLM_CONVERTING_LIST); + mlog(0, "node died with cancel pending " + "on %.*s. move back to granted list.\n", + res->lockname.len, res->lockname.name); + dlm_commit_pending_cancel(res, lock); + lock->cancel_pending = 0; + } + dlm_lock_put(lock); + } + } +} + + + +/* removes all recovered locks from the recovery list. + * sets the res->owner to the new master. + * unsets the RECOVERY flag and wakes waiters. */ +static void dlm_finish_local_lockres_recovery(struct dlm_ctxt *dlm, + u8 dead_node, u8 new_master) +{ + int i; + struct list_head *iter, *iter2, *bucket; + struct dlm_lock_resource *res; + + mlog_entry_void(); + + assert_spin_locked(&dlm->spinlock); + + list_for_each_safe(iter, iter2, &dlm->reco.resources) { + res = list_entry (iter, struct dlm_lock_resource, recovering); + if (res->owner == dead_node) { + list_del_init(&res->recovering); + spin_lock(&res->spinlock); + dlm_change_lockres_owner(dlm, res, new_master); + res->state &= ~DLM_LOCK_RES_RECOVERING; + __dlm_dirty_lockres(dlm, res); + spin_unlock(&res->spinlock); + wake_up(&res->wq); + } + } + + /* this will become unnecessary eventually, but + * for now we need to run the whole hash, clear + * the RECOVERING state and set the owner + * if necessary */ + for (i=0; i<DLM_HASH_SIZE; i++) { + bucket = &(dlm->resources[i]); + list_for_each(iter, bucket) { + res = list_entry (iter, struct dlm_lock_resource, list); + if (res->state & DLM_LOCK_RES_RECOVERING) { + if (res->owner == dead_node) { + mlog(0, "(this=%u) res %.*s owner=%u " + "was not on recovering list, but " + "clearing state anyway\n", + dlm->node_num, res->lockname.len, + res->lockname.name, new_master); + } else if (res->owner == dlm->node_num) { + mlog(0, "(this=%u) res %.*s owner=%u " + "was not on recovering list, " + "owner is THIS node, clearing\n", + dlm->node_num, res->lockname.len, + res->lockname.name, new_master); + } else + continue; + + spin_lock(&res->spinlock); + dlm_change_lockres_owner(dlm, res, new_master); + res->state &= ~DLM_LOCK_RES_RECOVERING; + __dlm_dirty_lockres(dlm, res); + spin_unlock(&res->spinlock); + wake_up(&res->wq); + } + } + } +} + +static inline int dlm_lvb_needs_invalidation(struct dlm_lock *lock, int local) +{ + if (local) { + if (lock->ml.type != LKM_EXMODE && + lock->ml.type != LKM_PRMODE) + return 1; + } else if (lock->ml.type == LKM_EXMODE) + return 1; + return 0; +} + +static void dlm_revalidate_lvb(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, u8 dead_node) +{ + struct list_head *iter, *queue; + struct dlm_lock *lock; + int blank_lvb = 0, local = 0; + int i; + u8 search_node; + + assert_spin_locked(&dlm->spinlock); + assert_spin_locked(&res->spinlock); + + if (res->owner == dlm->node_num) + /* if this node owned the lockres, and if the dead node + * had an EX when he died, blank out the lvb */ + search_node = dead_node; + else { + /* if this is a secondary lockres, and we had no EX or PR + * locks granted, we can no longer trust the lvb */ + search_node = dlm->node_num; + local = 1; /* check local state for valid lvb */ + } + + for (i=DLM_GRANTED_LIST; i<=DLM_CONVERTING_LIST; i++) { + queue = dlm_list_idx_to_ptr(res, i); + list_for_each(iter, queue) { + lock = list_entry (iter, struct dlm_lock, list); + if (lock->ml.node == search_node) { + if (dlm_lvb_needs_invalidation(lock, local)) { + /* zero the lksb lvb and lockres lvb */ + blank_lvb = 1; + memset(lock->lksb->lvb, 0, DLM_LVB_LEN); + } + } + } + } + + if (blank_lvb) { + mlog(0, "clearing %.*s lvb, dead node %u had EX\n", + res->lockname.len, res->lockname.name, dead_node); + memset(res->lvb, 0, DLM_LVB_LEN); + } +} + +static void dlm_free_dead_locks(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res, u8 dead_node) +{ + struct list_head *iter, *tmpiter; + struct dlm_lock *lock; + + /* this node is the lockres master: + * 1) remove any stale locks for the dead node + * 2) if the dead node had an EX when he died, blank out the lvb + */ + assert_spin_locked(&dlm->spinlock); + assert_spin_locked(&res->spinlock); + + /* TODO: check pending_asts, pending_basts here */ + list_for_each_safe(iter, tmpiter, &res->granted) { + lock = list_entry (iter, struct dlm_lock, list); + if (lock->ml.node == dead_node) { + list_del_init(&lock->list); + dlm_lock_put(lock); + } + } + list_for_each_safe(iter, tmpiter, &res->converting) { + lock = list_entry (iter, struct dlm_lock, list); + if (lock->ml.node == dead_node) { + list_del_init(&lock->list); + dlm_lock_put(lock); + } + } + list_for_each_safe(iter, tmpiter, &res->blocked) { + lock = list_entry (iter, struct dlm_lock, list); + if (lock->ml.node == dead_node) { + list_del_init(&lock->list); + dlm_lock_put(lock); + } + } + + /* do not kick thread yet */ + __dlm_dirty_lockres(dlm, res); +} + +/* if this node is the recovery master, and there are no + * locks for a given lockres owned by this node that are in + * either PR or EX mode, zero out the lvb before requesting. + * + */ + + +static void dlm_do_local_recovery_cleanup(struct dlm_ctxt *dlm, u8 dead_node) +{ + struct list_head *iter; + struct dlm_lock_resource *res; + int i; + struct list_head *bucket; + + + /* purge any stale mles */ + dlm_clean_master_list(dlm, dead_node); + + /* + * now clean up all lock resources. there are two rules: + * + * 1) if the dead node was the master, move the lockres + * to the recovering list. set the RECOVERING flag. + * this lockres needs to be cleaned up before it can + * be used further. + * + * 2) if this node was the master, remove all locks from + * each of the lockres queues that were owned by the + * dead node. once recovery finishes, the dlm thread + * can be kicked again to see if any ASTs or BASTs + * need to be fired as a result. + */ + for (i=0; i<DLM_HASH_SIZE; i++) { + bucket = &(dlm->resources[i]); + list_for_each(iter, bucket) { + res = list_entry (iter, struct dlm_lock_resource, list); + if (dlm_is_recovery_lock(res->lockname.name, + res->lockname.len)) + continue; + + spin_lock(&res->spinlock); + /* zero the lvb if necessary */ + dlm_revalidate_lvb(dlm, res, dead_node); + if (res->owner == dead_node) + dlm_move_lockres_to_recovery_list(dlm, res); + else if (res->owner == dlm->node_num) { + dlm_free_dead_locks(dlm, res, dead_node); + __dlm_lockres_calc_usage(dlm, res); + } + spin_unlock(&res->spinlock); + } + } + +} + +static void __dlm_hb_node_down(struct dlm_ctxt *dlm, int idx) +{ + assert_spin_locked(&dlm->spinlock); + + /* check to see if the node is already considered dead */ + if (!test_bit(idx, dlm->live_nodes_map)) { + mlog(0, "for domain %s, node %d is already dead. " + "another node likely did recovery already.\n", + dlm->name, idx); + return; + } + + /* check to see if we do not care about this node */ + if (!test_bit(idx, dlm->domain_map)) { + /* This also catches the case that we get a node down + * but haven't joined the domain yet. */ + mlog(0, "node %u already removed from domain!\n", idx); + return; + } + + clear_bit(idx, dlm->live_nodes_map); + + /* Clean up join state on node death. */ + if (dlm->joining_node == idx) { + mlog(0, "Clearing join state for node %u\n", idx); + __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN); + } + + /* make sure local cleanup occurs before the heartbeat events */ + if (!test_bit(idx, dlm->recovery_map)) + dlm_do_local_recovery_cleanup(dlm, idx); + + /* notify anything attached to the heartbeat events */ + dlm_hb_event_notify_attached(dlm, idx, 0); + + mlog(0, "node %u being removed from domain map!\n", idx); + clear_bit(idx, dlm->domain_map); + /* wake up migration waiters if a node goes down. + * perhaps later we can genericize this for other waiters. */ + wake_up(&dlm->migration_wq); + + if (test_bit(idx, dlm->recovery_map)) + mlog(0, "domain %s, node %u already added " + "to recovery map!\n", dlm->name, idx); + else + set_bit(idx, dlm->recovery_map); +} + +void dlm_hb_node_down_cb(struct o2nm_node *node, int idx, void *data) +{ + struct dlm_ctxt *dlm = data; + + if (!dlm_grab(dlm)) + return; + + spin_lock(&dlm->spinlock); + __dlm_hb_node_down(dlm, idx); + spin_unlock(&dlm->spinlock); + + dlm_put(dlm); +} + +void dlm_hb_node_up_cb(struct o2nm_node *node, int idx, void *data) +{ + struct dlm_ctxt *dlm = data; + + if (!dlm_grab(dlm)) + return; + + spin_lock(&dlm->spinlock); + + set_bit(idx, dlm->live_nodes_map); + + /* notify any mles attached to the heartbeat events */ + dlm_hb_event_notify_attached(dlm, idx, 1); + + spin_unlock(&dlm->spinlock); + + dlm_put(dlm); +} + +static void dlm_reco_ast(void *astdata) +{ + struct dlm_ctxt *dlm = astdata; + mlog(0, "ast for recovery lock fired!, this=%u, dlm=%s\n", + dlm->node_num, dlm->name); +} +static void dlm_reco_bast(void *astdata, int blocked_type) +{ + struct dlm_ctxt *dlm = astdata; + mlog(0, "bast for recovery lock fired!, this=%u, dlm=%s\n", + dlm->node_num, dlm->name); +} +static void dlm_reco_unlock_ast(void *astdata, enum dlm_status st) +{ + mlog(0, "unlockast for recovery lock fired!\n"); +} + + +static int dlm_pick_recovery_master(struct dlm_ctxt *dlm) +{ + enum dlm_status ret; + struct dlm_lockstatus lksb; + int status = -EINVAL; + + mlog(0, "starting recovery of %s at %lu, dead=%u, this=%u\n", + dlm->name, jiffies, dlm->reco.dead_node, dlm->node_num); +retry: + memset(&lksb, 0, sizeof(lksb)); + + ret = dlmlock(dlm, LKM_EXMODE, &lksb, LKM_NOQUEUE|LKM_RECOVERY, + DLM_RECOVERY_LOCK_NAME, dlm_reco_ast, dlm, dlm_reco_bast); + + if (ret == DLM_NORMAL) { + mlog(0, "dlm=%s dlmlock says I got it (this=%u)\n", + dlm->name, dlm->node_num); + /* I am master, send message to all nodes saying + * that I am beginning a recovery session */ + status = dlm_send_begin_reco_message(dlm, + dlm->reco.dead_node); + + /* recovery lock is a special case. ast will not get fired, + * so just go ahead and unlock it. */ + ret = dlmunlock(dlm, &lksb, 0, dlm_reco_unlock_ast, dlm); + if (ret != DLM_NORMAL) { + /* this would really suck. this could only happen + * if there was a network error during the unlock + * because of node death. this means the unlock + * is actually "done" and the lock structure is + * even freed. we can continue, but only + * because this specific lock name is special. */ + mlog(0, "dlmunlock returned %d\n", ret); + } + + if (status < 0) { + mlog(0, "failed to send recovery message. " + "must retry with new node map.\n"); + goto retry; + } + } else if (ret == DLM_NOTQUEUED) { + mlog(0, "dlm=%s dlmlock says another node got it (this=%u)\n", + dlm->name, dlm->node_num); + /* another node is master. wait on + * reco.new_master != O2NM_INVALID_NODE_NUM */ + status = -EEXIST; + } + + return status; +} + +static int dlm_send_begin_reco_message(struct dlm_ctxt *dlm, u8 dead_node) +{ + struct dlm_begin_reco br; + int ret = 0; + struct dlm_node_iter iter; + int nodenum; + int status; + + mlog_entry("%u\n", dead_node); + + mlog(0, "dead node is %u\n", dead_node); + + spin_lock(&dlm->spinlock); + dlm_node_iter_init(dlm->domain_map, &iter); + spin_unlock(&dlm->spinlock); + + clear_bit(dead_node, iter.node_map); + + memset(&br, 0, sizeof(br)); + br.node_idx = dlm->node_num; + br.dead_node = dead_node; + + while ((nodenum = dlm_node_iter_next(&iter)) >= 0) { + ret = 0; + if (nodenum == dead_node) { + mlog(0, "not sending begin reco to dead node " + "%u\n", dead_node); + continue; + } + if (nodenum == dlm->node_num) { + mlog(0, "not sending begin reco to self\n"); + continue; + } + + ret = -EINVAL; + mlog(0, "attempting to send begin reco msg to %d\n", + nodenum); + ret = o2net_send_message(DLM_BEGIN_RECO_MSG, dlm->key, + &br, sizeof(br), nodenum, &status); + /* negative status is handled ok by caller here */ + if (ret >= 0) + ret = status; + if (ret < 0) { + struct dlm_lock_resource *res; + mlog_errno(ret); + mlog(ML_ERROR, "begin reco of dlm %s to node %u " + " returned %d\n", dlm->name, nodenum, ret); + res = dlm_lookup_lockres(dlm, DLM_RECOVERY_LOCK_NAME, + DLM_RECOVERY_LOCK_NAME_LEN); + if (res) { + dlm_print_one_lock_resource(res); + dlm_lockres_put(res); + } else { + mlog(ML_ERROR, "recovery lock not found\n"); + } + break; + } + } + + return ret; +} + +int dlm_begin_reco_handler(struct o2net_msg *msg, u32 len, void *data) +{ + struct dlm_ctxt *dlm = data; + struct dlm_begin_reco *br = (struct dlm_begin_reco *)msg->buf; + + /* ok to return 0, domain has gone away */ + if (!dlm_grab(dlm)) + return 0; + + mlog(0, "node %u wants to recover node %u\n", + br->node_idx, br->dead_node); + + dlm_fire_domain_eviction_callbacks(dlm, br->dead_node); + + spin_lock(&dlm->spinlock); + if (dlm->reco.new_master != O2NM_INVALID_NODE_NUM) { + mlog(0, "new_master already set to %u!\n", + dlm->reco.new_master); + } + if (dlm->reco.dead_node != O2NM_INVALID_NODE_NUM) { + mlog(0, "dead_node already set to %u!\n", + dlm->reco.dead_node); + } + dlm->reco.new_master = br->node_idx; + dlm->reco.dead_node = br->dead_node; + if (!test_bit(br->dead_node, dlm->recovery_map)) { + mlog(ML_ERROR, "recovery master %u sees %u as dead, but this " + "node has not yet. marking %u as dead\n", + br->node_idx, br->dead_node, br->dead_node); + __dlm_hb_node_down(dlm, br->dead_node); + } + spin_unlock(&dlm->spinlock); + + dlm_kick_recovery_thread(dlm); + dlm_put(dlm); + return 0; +} + +static int dlm_send_finalize_reco_message(struct dlm_ctxt *dlm) +{ + int ret = 0; + struct dlm_finalize_reco fr; + struct dlm_node_iter iter; + int nodenum; + int status; + + mlog(0, "finishing recovery for node %s:%u\n", + dlm->name, dlm->reco.dead_node); + + spin_lock(&dlm->spinlock); + dlm_node_iter_init(dlm->domain_map, &iter); + spin_unlock(&dlm->spinlock); + + memset(&fr, 0, sizeof(fr)); + fr.node_idx = dlm->node_num; + fr.dead_node = dlm->reco.dead_node; + + while ((nodenum = dlm_node_iter_next(&iter)) >= 0) { + if (nodenum == dlm->node_num) + continue; + ret = o2net_send_message(DLM_FINALIZE_RECO_MSG, dlm->key, + &fr, sizeof(fr), nodenum, &status); + if (ret >= 0) { + ret = status; + if (dlm_is_host_down(ret)) { + /* this has no effect on this recovery + * session, so set the status to zero to + * finish out the last recovery */ + mlog(ML_ERROR, "node %u went down after this " + "node finished recovery.\n", nodenum); + ret = 0; + } + } + if (ret < 0) { + mlog_errno(ret); + break; + } + } + + return ret; +} + +int dlm_finalize_reco_handler(struct o2net_msg *msg, u32 len, void *data) +{ + struct dlm_ctxt *dlm = data; + struct dlm_finalize_reco *fr = (struct dlm_finalize_reco *)msg->buf; + + /* ok to return 0, domain has gone away */ + if (!dlm_grab(dlm)) + return 0; + + mlog(0, "node %u finalizing recovery of node %u\n", + fr->node_idx, fr->dead_node); + + spin_lock(&dlm->spinlock); + + if (dlm->reco.new_master != fr->node_idx) { + mlog(ML_ERROR, "node %u sent recovery finalize msg, but node " + "%u is supposed to be the new master, dead=%u\n", + fr->node_idx, dlm->reco.new_master, fr->dead_node); + BUG(); + } + if (dlm->reco.dead_node != fr->dead_node) { + mlog(ML_ERROR, "node %u sent recovery finalize msg for dead " + "node %u, but node %u is supposed to be dead\n", + fr->node_idx, fr->dead_node, dlm->reco.dead_node); + BUG(); + } + + dlm_finish_local_lockres_recovery(dlm, fr->dead_node, fr->node_idx); + + spin_unlock(&dlm->spinlock); + + dlm_reset_recovery(dlm); + + dlm_kick_recovery_thread(dlm); + dlm_put(dlm); + return 0; +} |