From e7fd41792fc0ee52a05fcaac87511f118328d147 Mon Sep 17 00:00:00 2001 From: David Teigland Date: Wed, 18 Jan 2006 09:30:29 +0000 Subject: [DLM] The core of the DLM for GFS2/CLVM This is the core of the distributed lock manager which is required to use GFS2 as a cluster filesystem. It is also used by CLVM and can be used as a standalone lock manager independantly of either of these two projects. It implements VAX-style locking modes. Signed-off-by: David Teigland Signed-off-by: Steve Whitehouse --- fs/dlm/rcom.c | 460 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 460 insertions(+) create mode 100644 fs/dlm/rcom.c (limited to 'fs/dlm/rcom.c') diff --git a/fs/dlm/rcom.c b/fs/dlm/rcom.c new file mode 100644 index 00000000000..4c5c08a8860 --- /dev/null +++ b/fs/dlm/rcom.c @@ -0,0 +1,460 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. +** Copyright (C) 2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +#include "dlm_internal.h" +#include "lockspace.h" +#include "member.h" +#include "lowcomms.h" +#include "midcomms.h" +#include "rcom.h" +#include "recover.h" +#include "dir.h" +#include "config.h" +#include "memory.h" +#include "lock.h" +#include "util.h" + + +static int rcom_response(struct dlm_ls *ls) +{ + return test_bit(LSFL_RCOM_READY, &ls->ls_flags); +} + +static int create_rcom(struct dlm_ls *ls, int to_nodeid, int type, int len, + struct dlm_rcom **rc_ret, struct dlm_mhandle **mh_ret) +{ + struct dlm_rcom *rc; + struct dlm_mhandle *mh; + char *mb; + int mb_len = sizeof(struct dlm_rcom) + len; + + mh = dlm_lowcomms_get_buffer(to_nodeid, mb_len, GFP_KERNEL, &mb); + if (!mh) { + log_print("create_rcom to %d type %d len %d ENOBUFS", + to_nodeid, type, len); + return -ENOBUFS; + } + memset(mb, 0, mb_len); + + rc = (struct dlm_rcom *) mb; + + rc->rc_header.h_version = (DLM_HEADER_MAJOR | DLM_HEADER_MINOR); + rc->rc_header.h_lockspace = ls->ls_global_id; + rc->rc_header.h_nodeid = dlm_our_nodeid(); + rc->rc_header.h_length = mb_len; + rc->rc_header.h_cmd = DLM_RCOM; + + rc->rc_type = type; + + *mh_ret = mh; + *rc_ret = rc; + return 0; +} + +static void send_rcom(struct dlm_ls *ls, struct dlm_mhandle *mh, + struct dlm_rcom *rc) +{ + dlm_rcom_out(rc); + dlm_lowcomms_commit_buffer(mh); +} + +/* When replying to a status request, a node also sends back its + configuration values. The requesting node then checks that the remote + node is configured the same way as itself. */ + +static void make_config(struct dlm_ls *ls, struct rcom_config *rf) +{ + rf->rf_lvblen = ls->ls_lvblen; + rf->rf_lsflags = ls->ls_exflags; +} + +static int check_config(struct dlm_ls *ls, struct rcom_config *rf, int nodeid) +{ + if (rf->rf_lvblen != ls->ls_lvblen || + rf->rf_lsflags != ls->ls_exflags) { + log_error(ls, "config mismatch: %d,%x nodeid %d: %d,%x", + ls->ls_lvblen, ls->ls_exflags, + nodeid, rf->rf_lvblen, rf->rf_lsflags); + return -EINVAL; + } + return 0; +} + +int dlm_rcom_status(struct dlm_ls *ls, int nodeid) +{ + struct dlm_rcom *rc; + struct dlm_mhandle *mh; + int error = 0; + + memset(ls->ls_recover_buf, 0, dlm_config.buffer_size); + + if (nodeid == dlm_our_nodeid()) { + rc = (struct dlm_rcom *) ls->ls_recover_buf; + rc->rc_result = dlm_recover_status(ls); + goto out; + } + + error = create_rcom(ls, nodeid, DLM_RCOM_STATUS, 0, &rc, &mh); + if (error) + goto out; + + send_rcom(ls, mh, rc); + + error = dlm_wait_function(ls, &rcom_response); + clear_bit(LSFL_RCOM_READY, &ls->ls_flags); + if (error) + goto out; + + rc = (struct dlm_rcom *) ls->ls_recover_buf; + + if (rc->rc_result == -ESRCH) { + /* we pretend the remote lockspace exists with 0 status */ + log_debug(ls, "remote node %d not ready", nodeid); + rc->rc_result = 0; + } else + error = check_config(ls, (struct rcom_config *) rc->rc_buf, + nodeid); + /* the caller looks at rc_result for the remote recovery status */ + out: + return error; +} + +static void receive_rcom_status(struct dlm_ls *ls, struct dlm_rcom *rc_in) +{ + struct dlm_rcom *rc; + struct dlm_mhandle *mh; + int error, nodeid = rc_in->rc_header.h_nodeid; + + error = create_rcom(ls, nodeid, DLM_RCOM_STATUS_REPLY, + sizeof(struct rcom_config), &rc, &mh); + if (error) + return; + rc->rc_result = dlm_recover_status(ls); + make_config(ls, (struct rcom_config *) rc->rc_buf); + + send_rcom(ls, mh, rc); +} + +static void receive_rcom_status_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in) +{ + memcpy(ls->ls_recover_buf, rc_in, rc_in->rc_header.h_length); + set_bit(LSFL_RCOM_READY, &ls->ls_flags); + wake_up(&ls->ls_wait_general); +} + +int dlm_rcom_names(struct dlm_ls *ls, int nodeid, char *last_name, int last_len) +{ + struct dlm_rcom *rc; + struct dlm_mhandle *mh; + int error = 0, len = sizeof(struct dlm_rcom); + + memset(ls->ls_recover_buf, 0, dlm_config.buffer_size); + + if (nodeid == dlm_our_nodeid()) { + dlm_copy_master_names(ls, last_name, last_len, + ls->ls_recover_buf + len, + dlm_config.buffer_size - len, nodeid); + goto out; + } + + error = create_rcom(ls, nodeid, DLM_RCOM_NAMES, last_len, &rc, &mh); + if (error) + goto out; + memcpy(rc->rc_buf, last_name, last_len); + + send_rcom(ls, mh, rc); + + error = dlm_wait_function(ls, &rcom_response); + clear_bit(LSFL_RCOM_READY, &ls->ls_flags); + out: + return error; +} + +static void receive_rcom_names(struct dlm_ls *ls, struct dlm_rcom *rc_in) +{ + struct dlm_rcom *rc; + struct dlm_mhandle *mh; + int error, inlen, outlen; + int nodeid = rc_in->rc_header.h_nodeid; + uint32_t status = dlm_recover_status(ls); + + /* + * We can't run dlm_dir_rebuild_send (which uses ls_nodes) while + * dlm_recoverd is running ls_nodes_reconfig (which changes ls_nodes). + * It could only happen in rare cases where we get a late NAMES + * message from a previous instance of recovery. + */ + + if (!(status & DLM_RS_NODES)) { + log_debug(ls, "ignoring RCOM_NAMES from %u", nodeid); + return; + } + + nodeid = rc_in->rc_header.h_nodeid; + inlen = rc_in->rc_header.h_length - sizeof(struct dlm_rcom); + outlen = dlm_config.buffer_size - sizeof(struct dlm_rcom); + + error = create_rcom(ls, nodeid, DLM_RCOM_NAMES_REPLY, outlen, &rc, &mh); + if (error) + return; + + dlm_copy_master_names(ls, rc_in->rc_buf, inlen, rc->rc_buf, outlen, + nodeid); + send_rcom(ls, mh, rc); +} + +static void receive_rcom_names_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in) +{ + memcpy(ls->ls_recover_buf, rc_in, rc_in->rc_header.h_length); + set_bit(LSFL_RCOM_READY, &ls->ls_flags); + wake_up(&ls->ls_wait_general); +} + +int dlm_send_rcom_lookup(struct dlm_rsb *r, int dir_nodeid) +{ + struct dlm_rcom *rc; + struct dlm_mhandle *mh; + struct dlm_ls *ls = r->res_ls; + int error; + + error = create_rcom(ls, dir_nodeid, DLM_RCOM_LOOKUP, r->res_length, + &rc, &mh); + if (error) + goto out; + memcpy(rc->rc_buf, r->res_name, r->res_length); + rc->rc_id = (unsigned long) r; + + send_rcom(ls, mh, rc); + out: + return error; +} + +static void receive_rcom_lookup(struct dlm_ls *ls, struct dlm_rcom *rc_in) +{ + struct dlm_rcom *rc; + struct dlm_mhandle *mh; + int error, ret_nodeid, nodeid = rc_in->rc_header.h_nodeid; + int len = rc_in->rc_header.h_length - sizeof(struct dlm_rcom); + + error = create_rcom(ls, nodeid, DLM_RCOM_LOOKUP_REPLY, 0, &rc, &mh); + if (error) + return; + + error = dlm_dir_lookup(ls, nodeid, rc_in->rc_buf, len, &ret_nodeid); + if (error) + ret_nodeid = error; + rc->rc_result = ret_nodeid; + rc->rc_id = rc_in->rc_id; + + send_rcom(ls, mh, rc); +} + +static void receive_rcom_lookup_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in) +{ + dlm_recover_master_reply(ls, rc_in); +} + +static void pack_rcom_lock(struct dlm_rsb *r, struct dlm_lkb *lkb, + struct rcom_lock *rl) +{ + memset(rl, 0, sizeof(*rl)); + + rl->rl_ownpid = lkb->lkb_ownpid; + rl->rl_lkid = lkb->lkb_id; + rl->rl_exflags = lkb->lkb_exflags; + rl->rl_flags = lkb->lkb_flags; + rl->rl_lvbseq = lkb->lkb_lvbseq; + rl->rl_rqmode = lkb->lkb_rqmode; + rl->rl_grmode = lkb->lkb_grmode; + rl->rl_status = lkb->lkb_status; + rl->rl_wait_type = lkb->lkb_wait_type; + + if (lkb->lkb_bastaddr) + rl->rl_asts |= AST_BAST; + if (lkb->lkb_astaddr) + rl->rl_asts |= AST_COMP; + + if (lkb->lkb_range) + memcpy(rl->rl_range, lkb->lkb_range, 4*sizeof(uint64_t)); + + rl->rl_namelen = r->res_length; + memcpy(rl->rl_name, r->res_name, r->res_length); + + /* FIXME: might we have an lvb without DLM_LKF_VALBLK set ? + If so, receive_rcom_lock_args() won't take this copy. */ + + if (lkb->lkb_lvbptr) + memcpy(rl->rl_lvb, lkb->lkb_lvbptr, r->res_ls->ls_lvblen); +} + +int dlm_send_rcom_lock(struct dlm_rsb *r, struct dlm_lkb *lkb) +{ + struct dlm_ls *ls = r->res_ls; + struct dlm_rcom *rc; + struct dlm_mhandle *mh; + struct rcom_lock *rl; + int error, len = sizeof(struct rcom_lock); + + if (lkb->lkb_lvbptr) + len += ls->ls_lvblen; + + error = create_rcom(ls, r->res_nodeid, DLM_RCOM_LOCK, len, &rc, &mh); + if (error) + goto out; + + rl = (struct rcom_lock *) rc->rc_buf; + pack_rcom_lock(r, lkb, rl); + rc->rc_id = (unsigned long) r; + + send_rcom(ls, mh, rc); + out: + return error; +} + +static void receive_rcom_lock(struct dlm_ls *ls, struct dlm_rcom *rc_in) +{ + struct dlm_rcom *rc; + struct dlm_mhandle *mh; + int error, nodeid = rc_in->rc_header.h_nodeid; + + dlm_recover_master_copy(ls, rc_in); + + error = create_rcom(ls, nodeid, DLM_RCOM_LOCK_REPLY, + sizeof(struct rcom_lock), &rc, &mh); + if (error) + return; + + /* We send back the same rcom_lock struct we received, but + dlm_recover_master_copy() has filled in rl_remid and rl_result */ + + memcpy(rc->rc_buf, rc_in->rc_buf, sizeof(struct rcom_lock)); + rc->rc_id = rc_in->rc_id; + + send_rcom(ls, mh, rc); +} + +static void receive_rcom_lock_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in) +{ + uint32_t status = dlm_recover_status(ls); + + if (!(status & DLM_RS_DIR)) { + log_debug(ls, "ignoring RCOM_LOCK_REPLY from %u", + rc_in->rc_header.h_nodeid); + return; + } + + dlm_recover_process_copy(ls, rc_in); +} + +static int send_ls_not_ready(int nodeid, struct dlm_rcom *rc_in) +{ + struct dlm_rcom *rc; + struct dlm_mhandle *mh; + char *mb; + int mb_len = sizeof(struct dlm_rcom); + + mh = dlm_lowcomms_get_buffer(nodeid, mb_len, GFP_KERNEL, &mb); + if (!mh) + return -ENOBUFS; + memset(mb, 0, mb_len); + + rc = (struct dlm_rcom *) mb; + + rc->rc_header.h_version = (DLM_HEADER_MAJOR | DLM_HEADER_MINOR); + rc->rc_header.h_lockspace = rc_in->rc_header.h_lockspace; + rc->rc_header.h_nodeid = dlm_our_nodeid(); + rc->rc_header.h_length = mb_len; + rc->rc_header.h_cmd = DLM_RCOM; + + rc->rc_type = DLM_RCOM_STATUS_REPLY; + rc->rc_result = -ESRCH; + + dlm_rcom_out(rc); + dlm_lowcomms_commit_buffer(mh); + + return 0; +} + +/* Called by dlm_recvd; corresponds to dlm_receive_message() but special + recovery-only comms are sent through here. */ + +void dlm_receive_rcom(struct dlm_header *hd, int nodeid) +{ + struct dlm_rcom *rc = (struct dlm_rcom *) hd; + struct dlm_ls *ls; + + dlm_rcom_in(rc); + + /* If the lockspace doesn't exist then still send a status message + back; it's possible that it just doesn't have its global_id yet. */ + + ls = dlm_find_lockspace_global(hd->h_lockspace); + if (!ls) { + log_print("lockspace %x from %d not found", + hd->h_lockspace, nodeid); + send_ls_not_ready(nodeid, rc); + return; + } + + if (dlm_recovery_stopped(ls) && (rc->rc_type != DLM_RCOM_STATUS)) { + log_error(ls, "ignoring recovery message %x from %d", + rc->rc_type, nodeid); + goto out; + } + + if (nodeid != rc->rc_header.h_nodeid) { + log_error(ls, "bad rcom nodeid %d from %d", + rc->rc_header.h_nodeid, nodeid); + goto out; + } + + switch (rc->rc_type) { + case DLM_RCOM_STATUS: + receive_rcom_status(ls, rc); + break; + + case DLM_RCOM_NAMES: + receive_rcom_names(ls, rc); + break; + + case DLM_RCOM_LOOKUP: + receive_rcom_lookup(ls, rc); + break; + + case DLM_RCOM_LOCK: + receive_rcom_lock(ls, rc); + break; + + case DLM_RCOM_STATUS_REPLY: + receive_rcom_status_reply(ls, rc); + break; + + case DLM_RCOM_NAMES_REPLY: + receive_rcom_names_reply(ls, rc); + break; + + case DLM_RCOM_LOOKUP_REPLY: + receive_rcom_lookup_reply(ls, rc); + break; + + case DLM_RCOM_LOCK_REPLY: + receive_rcom_lock_reply(ls, rc); + break; + + default: + DLM_ASSERT(0, printk("rc_type=%x\n", rc->rc_type);); + } + out: + dlm_put_lockspace(ls); +} + -- cgit v1.2.3