/* -*- mode: c; c-basic-offset: 8; -*- * vim: noexpandtab sw=8 ts=8 sts=0: * * vote.c * * description here * * Copyright (C) 2003, 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/types.h> #include <linux/slab.h> #include <linux/highmem.h> #include <linux/kthread.h> #include <cluster/heartbeat.h> #include <cluster/nodemanager.h> #include <cluster/tcp.h> #include <dlm/dlmapi.h> #define MLOG_MASK_PREFIX ML_VOTE #include <cluster/masklog.h> #include "ocfs2.h" #include "alloc.h" #include "dlmglue.h" #include "extent_map.h" #include "heartbeat.h" #include "inode.h" #include "journal.h" #include "slot_map.h" #include "vote.h" #include "buffer_head_io.h" #define OCFS2_MESSAGE_TYPE_VOTE (0x1) #define OCFS2_MESSAGE_TYPE_RESPONSE (0x2) struct ocfs2_msg_hdr { __be32 h_response_id; /* used to lookup message handle on sending * node. */ __be32 h_request; __be64 h_blkno; __be32 h_generation; __be32 h_node_num; /* node sending this particular message. */ }; struct ocfs2_vote_msg { struct ocfs2_msg_hdr v_hdr; __be32 v_reserved1; } __attribute__ ((packed)); /* Responses are given these values to maintain backwards * compatibility with older ocfs2 versions */ #define OCFS2_RESPONSE_OK (0) #define OCFS2_RESPONSE_BUSY (-16) #define OCFS2_RESPONSE_BAD_MSG (-22) struct ocfs2_response_msg { struct ocfs2_msg_hdr r_hdr; __be32 r_response; } __attribute__ ((packed)); struct ocfs2_vote_work { struct list_head w_list; struct ocfs2_vote_msg w_msg; }; enum ocfs2_vote_request { OCFS2_VOTE_REQ_INVALID = 0, OCFS2_VOTE_REQ_MOUNT, OCFS2_VOTE_REQ_UMOUNT, OCFS2_VOTE_REQ_LAST }; static inline int ocfs2_is_valid_vote_request(int request) { return OCFS2_VOTE_REQ_INVALID < request && request < OCFS2_VOTE_REQ_LAST; } typedef void (*ocfs2_net_response_callback)(void *priv, struct ocfs2_response_msg *resp); struct ocfs2_net_response_cb { ocfs2_net_response_callback rc_cb; void *rc_priv; }; struct ocfs2_net_wait_ctxt { struct list_head n_list; u32 n_response_id; wait_queue_head_t n_event; struct ocfs2_node_map n_node_map; int n_response; /* an agreggate response. 0 if * all nodes are go, < 0 on any * negative response from any * node or network error. */ struct ocfs2_net_response_cb *n_callback; }; static void ocfs2_process_mount_request(struct ocfs2_super *osb, unsigned int node_num) { mlog(0, "MOUNT vote from node %u\n", node_num); /* The other node only sends us this message when he has an EX * on the superblock, so our recovery threads (if having been * launched) are waiting on it.*/ ocfs2_recovery_map_clear(osb, node_num); ocfs2_node_map_set_bit(osb, &osb->mounted_map, node_num); /* We clear the umount map here because a node may have been * previously mounted, safely unmounted but never stopped * heartbeating - in which case we'd have a stale entry. */ ocfs2_node_map_clear_bit(osb, &osb->umount_map, node_num); } static void ocfs2_process_umount_request(struct ocfs2_super *osb, unsigned int node_num) { mlog(0, "UMOUNT vote from node %u\n", node_num); ocfs2_node_map_clear_bit(osb, &osb->mounted_map, node_num); ocfs2_node_map_set_bit(osb, &osb->umount_map, node_num); } static void ocfs2_process_vote(struct ocfs2_super *osb, struct ocfs2_vote_msg *msg) { int net_status, vote_response; unsigned int node_num; u64 blkno; enum ocfs2_vote_request request; struct ocfs2_msg_hdr *hdr = &msg->v_hdr; struct ocfs2_response_msg response; /* decode the network mumbo jumbo into local variables. */ request = be32_to_cpu(hdr->h_request); blkno = be64_to_cpu(hdr->h_blkno); node_num = be32_to_cpu(hdr->h_node_num); mlog(0, "processing vote: request = %u, blkno = %llu, node_num = %u\n", request, (unsigned long long)blkno, node_num); if (!ocfs2_is_valid_vote_request(request)) { mlog(ML_ERROR, "Invalid vote request %d from node %u\n", request, node_num); vote_response = OCFS2_RESPONSE_BAD_MSG; goto respond; } vote_response = OCFS2_RESPONSE_OK; switch (request) { case OCFS2_VOTE_REQ_UMOUNT: ocfs2_process_umount_request(osb, node_num); goto respond; case OCFS2_VOTE_REQ_MOUNT: ocfs2_process_mount_request(osb, node_num); goto respond; default: /* avoids a gcc warning */ break; } respond: /* Response struture is small so we just put it on the stack * and stuff it inline. */ memset(&response, 0, sizeof(struct ocfs2_response_msg)); response.r_hdr.h_response_id = hdr->h_response_id; response.r_hdr.h_blkno = hdr->h_blkno; response.r_hdr.h_generation = hdr->h_generation; response.r_hdr.h_node_num = cpu_to_be32(osb->node_num); response.r_response = cpu_to_be32(vote_response); net_status = o2net_send_message(OCFS2_MESSAGE_TYPE_RESPONSE, osb->net_key, &response, sizeof(struct ocfs2_response_msg), node_num, NULL); /* We still want to error print for ENOPROTOOPT here. The * sending node shouldn't have unregistered his net handler * without sending an unmount vote 1st */ if (net_status < 0 && net_status != -ETIMEDOUT && net_status != -ENOTCONN) mlog(ML_ERROR, "message to node %u fails with error %d!\n", node_num, net_status); } static void ocfs2_vote_thread_do_work(struct ocfs2_super *osb) { unsigned long processed; struct ocfs2_lock_res *lockres; struct ocfs2_vote_work *work; mlog_entry_void(); spin_lock(&osb->vote_task_lock); /* grab this early so we know to try again if a state change and * wake happens part-way through our work */ osb->vote_work_sequence = osb->vote_wake_sequence; processed = osb->blocked_lock_count; while (processed) { BUG_ON(list_empty(&osb->blocked_lock_list)); lockres = list_entry(osb->blocked_lock_list.next, struct ocfs2_lock_res, l_blocked_list); list_del_init(&lockres->l_blocked_list); osb->blocked_lock_count--; spin_unlock(&osb->vote_task_lock); BUG_ON(!processed); processed--; ocfs2_process_blocked_lock(osb, lockres); spin_lock(&osb->vote_task_lock); } while (osb->vote_count) { BUG_ON(list_empty(&osb->vote_list)); work = list_entry(osb->vote_list.next, struct ocfs2_vote_work, w_list); list_del(&work->w_list); osb->vote_count--; spin_unlock(&osb->vote_task_lock); ocfs2_process_vote(osb, &work->w_msg); kfree(work); spin_lock(&osb->vote_task_lock); } spin_unlock(&osb->vote_task_lock); mlog_exit_void(); } static int ocfs2_vote_thread_lists_empty(struct ocfs2_super *osb) { int empty = 0; spin_lock(&osb->vote_task_lock); if (list_empty(&osb->blocked_lock_list) && list_empty(&osb->vote_list)) empty = 1; spin_unlock(&osb->vote_task_lock); return empty; } static int ocfs2_vote_thread_should_wake(struct ocfs2_super *osb) { int should_wake = 0; spin_lock(&osb->vote_task_lock); if (osb->vote_work_sequence != osb->vote_wake_sequence) should_wake = 1; spin_unlock(&osb->vote_task_lock); return should_wake; } int ocfs2_vote_thread(void *arg) { int status = 0; struct ocfs2_super *osb = arg; /* only quit once we've been asked to stop and there is no more * work available */ while (!(kthread_should_stop() && ocfs2_vote_thread_lists_empty(osb))) { wait_event_interruptible(osb->vote_event, ocfs2_vote_thread_should_wake(osb) || kthread_should_stop()); mlog(0, "vote_thread: awoken\n"); ocfs2_vote_thread_do_work(osb); } osb->vote_task = NULL; return status; } static struct ocfs2_net_wait_ctxt *ocfs2_new_net_wait_ctxt(unsigned int response_id) { struct ocfs2_net_wait_ctxt *w; w = kzalloc(sizeof(*w), GFP_NOFS); if (!w) { mlog_errno(-ENOMEM); goto bail; } INIT_LIST_HEAD(&w->n_list); init_waitqueue_head(&w->n_event); ocfs2_node_map_init(&w->n_node_map); w->n_response_id = response_id; w->n_callback = NULL; bail: return w; } static unsigned int ocfs2_new_response_id(struct ocfs2_super *osb) { unsigned int ret; spin_lock(&osb->net_response_lock); ret = ++osb->net_response_ids; spin_unlock(&osb->net_response_lock); return ret; } static void ocfs2_dequeue_net_wait_ctxt(struct ocfs2_super *osb, struct ocfs2_net_wait_ctxt *w) { spin_lock(&osb->net_response_lock); list_del(&w->n_list); spin_unlock(&osb->net_response_lock); } static void ocfs2_queue_net_wait_ctxt(struct ocfs2_super *osb, struct ocfs2_net_wait_ctxt *w) { spin_lock(&osb->net_response_lock); list_add_tail(&w->n_list, &osb->net_response_list); spin_unlock(&osb->net_response_lock); } static void __ocfs2_mark_node_responded(struct ocfs2_super *osb, struct ocfs2_net_wait_ctxt *w, int node_num) { assert_spin_locked(&osb->net_response_lock); ocfs2_node_map_clear_bit(osb, &w->n_node_map, node_num); if (ocfs2_node_map_is_empty(osb, &w->n_node_map)) wake_up(&w->n_event); } /* Intended to be called from the node down callback, we fake remove * the node from all our response contexts */ void ocfs2_remove_node_from_vote_queues(struct ocfs2_super *osb, int node_num) { struct list_head *p; struct ocfs2_net_wait_ctxt *w = NULL; spin_lock(&osb->net_response_lock); list_for_each(p, &osb->net_response_list) { w = list_entry(p, struct ocfs2_net_wait_ctxt, n_list); __ocfs2_mark_node_responded(osb, w, node_num); } spin_unlock(&osb->net_response_lock); } static int ocfs2_broadcast_vote(struct ocfs2_super *osb, struct ocfs2_vote_msg *request, unsigned int response_id, int *response, struct ocfs2_net_response_cb *callback) { int status, i, remote_err; struct ocfs2_net_wait_ctxt *w = NULL; int dequeued = 0; mlog_entry_void(); w = ocfs2_new_net_wait_ctxt(response_id); if (!w) { status = -ENOMEM; mlog_errno(status); goto bail; } w->n_callback = callback; /* we're pretty much ready to go at this point, and this fills * in n_response which we need anyway... */ ocfs2_queue_net_wait_ctxt(osb, w); i = ocfs2_node_map_iterate(osb, &osb->mounted_map, 0); while (i != O2NM_INVALID_NODE_NUM) { if (i != osb->node_num) { mlog(0, "trying to send request to node %i\n", i); ocfs2_node_map_set_bit(osb, &w->n_node_map, i); remote_err = 0; status = o2net_send_message(OCFS2_MESSAGE_TYPE_VOTE, osb->net_key, request, sizeof(*request), i, &remote_err); if (status == -ETIMEDOUT) { mlog(0, "remote node %d timed out!\n", i); status = -EAGAIN; goto bail; } if (remote_err < 0) { status = remote_err; mlog(0, "remote error %d on node %d!\n", remote_err, i); mlog_errno(status); goto bail; } if (status < 0) { mlog_errno(status); goto bail; } } i++; i = ocfs2_node_map_iterate(osb, &osb->mounted_map, i); mlog(0, "next is %d, i am %d\n", i, osb->node_num); } mlog(0, "done sending, now waiting on responses...\n"); wait_event(w->n_event, ocfs2_node_map_is_empty(osb, &w->n_node_map)); ocfs2_dequeue_net_wait_ctxt(osb, w); dequeued = 1; *response = w->n_response; status = 0; bail: if (w) { if (!dequeued) ocfs2_dequeue_net_wait_ctxt(osb, w); kfree(w); } mlog_exit(status); return status; } static struct ocfs2_vote_msg * ocfs2_new_vote_request(struct ocfs2_super *osb, u64 blkno, unsigned int generation, enum ocfs2_vote_request type) { struct ocfs2_vote_msg *request; struct ocfs2_msg_hdr *hdr; BUG_ON(!ocfs2_is_valid_vote_request(type)); request = kzalloc(sizeof(*request), GFP_NOFS); if (!request) { mlog_errno(-ENOMEM); } else { hdr = &request->v_hdr; hdr->h_node_num = cpu_to_be32(osb->node_num); hdr->h_request = cpu_to_be32(type); hdr->h_blkno = cpu_to_be64(blkno); hdr->h_generation = cpu_to_be32(generation); } return request; } /* Complete the buildup of a new vote request and process the * broadcast return value. */ static int ocfs2_do_request_vote(struct ocfs2_super *osb, struct ocfs2_vote_msg *request, struct ocfs2_net_response_cb *callback) { int status, response = -EBUSY; unsigned int response_id; struct ocfs2_msg_hdr *hdr; response_id = ocfs2_new_response_id(osb); hdr = &request->v_hdr; hdr->h_response_id = cpu_to_be32(response_id); status = ocfs2_broadcast_vote(osb, request, response_id, &response, callback); if (status < 0) { mlog_errno(status); goto bail; } status = response; bail: return status; } int ocfs2_request_mount_vote(struct ocfs2_super *osb) { int status; struct ocfs2_vote_msg *request = NULL; request = ocfs2_new_vote_request(osb, 0ULL, 0, OCFS2_VOTE_REQ_MOUNT); if (!request) { status = -ENOMEM; goto bail; } status = -EAGAIN; while (status == -EAGAIN) { if (!(osb->s_mount_opt & OCFS2_MOUNT_NOINTR) && signal_pending(current)) { status = -ERESTARTSYS; goto bail; } if (ocfs2_node_map_is_only(osb, &osb->mounted_map, osb->node_num)) { status = 0; goto bail; } status = ocfs2_do_request_vote(osb, request, NULL); } bail: kfree(request); return status; } int ocfs2_request_umount_vote(struct ocfs2_super *osb) { int status; struct ocfs2_vote_msg *request = NULL; request = ocfs2_new_vote_request(osb, 0ULL, 0, OCFS2_VOTE_REQ_UMOUNT); if (!request) { status = -ENOMEM; goto bail; } status = -EAGAIN; while (status == -EAGAIN) { /* Do not check signals on this vote... We really want * this one to go all the way through. */ if (ocfs2_node_map_is_only(osb, &osb->mounted_map, osb->node_num)) { status = 0; goto bail; } status = ocfs2_do_request_vote(osb, request, NULL); } bail: kfree(request); return status; } /* TODO: This should eventually be a hash table! */ static struct ocfs2_net_wait_ctxt * __ocfs2_find_net_wait_ctxt(struct ocfs2_super *osb, u32 response_id) { struct list_head *p; struct ocfs2_net_wait_ctxt *w = NULL; list_for_each(p, &osb->net_response_list) { w = list_entry(p, struct ocfs2_net_wait_ctxt, n_list); if (response_id == w->n_response_id) break; w = NULL; } return w; } /* Translate response codes into local node errno values */ static inline int ocfs2_translate_response(int response) { int ret; switch (response) { case OCFS2_RESPONSE_OK: ret = 0; break; case OCFS2_RESPONSE_BUSY: ret = -EBUSY; break; default: ret = -EINVAL; } return ret; } static int ocfs2_handle_response_message(struct o2net_msg *msg, u32 len, void *data, void **ret_data) { unsigned int response_id, node_num; int response_status; struct ocfs2_super *osb = data; struct ocfs2_response_msg *resp; struct ocfs2_net_wait_ctxt * w; struct ocfs2_net_response_cb *resp_cb; resp = (struct ocfs2_response_msg *) msg->buf; response_id = be32_to_cpu(resp->r_hdr.h_response_id); node_num = be32_to_cpu(resp->r_hdr.h_node_num); response_status = ocfs2_translate_response(be32_to_cpu(resp->r_response)); mlog(0, "received response message:\n"); mlog(0, "h_response_id = %u\n", response_id); mlog(0, "h_request = %u\n", be32_to_cpu(resp->r_hdr.h_request)); mlog(0, "h_blkno = %llu\n", (unsigned long long)be64_to_cpu(resp->r_hdr.h_blkno)); mlog(0, "h_generation = %u\n", be32_to_cpu(resp->r_hdr.h_generation)); mlog(0, "h_node_num = %u\n", node_num); mlog(0, "r_response = %d\n", response_status); spin_lock(&osb->net_response_lock); w = __ocfs2_find_net_wait_ctxt(osb, response_id); if (!w) { mlog(0, "request not found!\n"); goto bail; } resp_cb = w->n_callback; if (response_status && (!w->n_response)) { /* we only really need one negative response so don't * set it twice. */ w->n_response = response_status; } if (resp_cb) { spin_unlock(&osb->net_response_lock); resp_cb->rc_cb(resp_cb->rc_priv, resp); spin_lock(&osb->net_response_lock); } __ocfs2_mark_node_responded(osb, w, node_num); bail: spin_unlock(&osb->net_response_lock); return 0; } static int ocfs2_handle_vote_message(struct o2net_msg *msg, u32 len, void *data, void **ret_data) { int status; struct ocfs2_super *osb = data; struct ocfs2_vote_work *work; work = kmalloc(sizeof(struct ocfs2_vote_work), GFP_NOFS); if (!work) { status = -ENOMEM; mlog_errno(status); goto bail; } INIT_LIST_HEAD(&work->w_list); memcpy(&work->w_msg, msg->buf, sizeof(struct ocfs2_vote_msg)); mlog(0, "scheduling vote request:\n"); mlog(0, "h_response_id = %u\n", be32_to_cpu(work->w_msg.v_hdr.h_response_id)); mlog(0, "h_request = %u\n", be32_to_cpu(work->w_msg.v_hdr.h_request)); mlog(0, "h_blkno = %llu\n", (unsigned long long)be64_to_cpu(work->w_msg.v_hdr.h_blkno)); mlog(0, "h_generation = %u\n", be32_to_cpu(work->w_msg.v_hdr.h_generation)); mlog(0, "h_node_num = %u\n", be32_to_cpu(work->w_msg.v_hdr.h_node_num)); spin_lock(&osb->vote_task_lock); list_add_tail(&work->w_list, &osb->vote_list); osb->vote_count++; spin_unlock(&osb->vote_task_lock); ocfs2_kick_vote_thread(osb); status = 0; bail: return status; } void ocfs2_unregister_net_handlers(struct ocfs2_super *osb) { if (!osb->net_key) return; o2net_unregister_handler_list(&osb->osb_net_handlers); if (!list_empty(&osb->net_response_list)) mlog(ML_ERROR, "net response list not empty!\n"); osb->net_key = 0; } int ocfs2_register_net_handlers(struct ocfs2_super *osb) { int status = 0; if (ocfs2_mount_local(osb)) return 0; status = o2net_register_handler(OCFS2_MESSAGE_TYPE_RESPONSE, osb->net_key, sizeof(struct ocfs2_response_msg), ocfs2_handle_response_message, osb, NULL, &osb->osb_net_handlers); if (status) { mlog_errno(status); goto bail; } status = o2net_register_handler(OCFS2_MESSAGE_TYPE_VOTE, osb->net_key, sizeof(struct ocfs2_vote_msg), ocfs2_handle_vote_message, osb, NULL, &osb->osb_net_handlers); if (status) { mlog_errno(status); goto bail; } bail: if (status < 0) ocfs2_unregister_net_handlers(osb); return status; }