linux-stable/fs/dlm/rcom.c
David Teigland 8304d6f24c dlm: record full callback state
Change how callbacks are recorded for locks.  Previously, information
about multiple callbacks was combined into a couple of variables that
indicated what the end result should be.  In some situations, we
could not tell from this combined state what the exact sequence of
callbacks were, and would end up either delivering the callbacks in
the wrong order, or suppress redundant callbacks incorrectly.  This
new approach records all the data for each callback, leaving no
uncertainty about what needs to be delivered.

Signed-off-by: David Teigland <teigland@redhat.com>
2011-03-10 10:40:00 -06:00

511 lines
13 KiB
C

/******************************************************************************
*******************************************************************************
**
** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
** Copyright (C) 2005-2008 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_NOFS, &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;
spin_lock(&ls->ls_recover_lock);
rc->rc_seq = ls->ls_recover_seq;
spin_unlock(&ls->ls_recover_lock);
*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 = cpu_to_le32(ls->ls_lvblen);
rf->rf_lsflags = cpu_to_le32(ls->ls_exflags);
}
static int check_config(struct dlm_ls *ls, struct dlm_rcom *rc, int nodeid)
{
struct rcom_config *rf = (struct rcom_config *) rc->rc_buf;
size_t conf_size = sizeof(struct dlm_rcom) + sizeof(struct rcom_config);
if ((rc->rc_header.h_version & 0xFFFF0000) != DLM_HEADER_MAJOR) {
log_error(ls, "version mismatch: %x nodeid %d: %x",
DLM_HEADER_MAJOR | DLM_HEADER_MINOR, nodeid,
rc->rc_header.h_version);
return -EPROTO;
}
if (rc->rc_header.h_length < conf_size) {
log_error(ls, "config too short: %d nodeid %d",
rc->rc_header.h_length, nodeid);
return -EPROTO;
}
if (le32_to_cpu(rf->rf_lvblen) != ls->ls_lvblen ||
le32_to_cpu(rf->rf_lsflags) != ls->ls_exflags) {
log_error(ls, "config mismatch: %d,%x nodeid %d: %d,%x",
ls->ls_lvblen, ls->ls_exflags, nodeid,
le32_to_cpu(rf->rf_lvblen),
le32_to_cpu(rf->rf_lsflags));
return -EPROTO;
}
return 0;
}
static void allow_sync_reply(struct dlm_ls *ls, uint64_t *new_seq)
{
spin_lock(&ls->ls_rcom_spin);
*new_seq = ++ls->ls_rcom_seq;
set_bit(LSFL_RCOM_WAIT, &ls->ls_flags);
spin_unlock(&ls->ls_rcom_spin);
}
static void disallow_sync_reply(struct dlm_ls *ls)
{
spin_lock(&ls->ls_rcom_spin);
clear_bit(LSFL_RCOM_WAIT, &ls->ls_flags);
clear_bit(LSFL_RCOM_READY, &ls->ls_flags);
spin_unlock(&ls->ls_rcom_spin);
}
int dlm_rcom_status(struct dlm_ls *ls, int nodeid)
{
struct dlm_rcom *rc;
struct dlm_mhandle *mh;
int error = 0;
ls->ls_recover_nodeid = nodeid;
if (nodeid == dlm_our_nodeid()) {
rc = 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;
allow_sync_reply(ls, &rc->rc_id);
memset(ls->ls_recover_buf, 0, dlm_config.ci_buffer_size);
send_rcom(ls, mh, rc);
error = dlm_wait_function(ls, &rcom_response);
disallow_sync_reply(ls);
if (error)
goto out;
rc = 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, rc, 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_id = rc_in->rc_id;
rc->rc_seq_reply = rc_in->rc_seq;
rc->rc_result = dlm_recover_status(ls);
make_config(ls, (struct rcom_config *) rc->rc_buf);
send_rcom(ls, mh, rc);
}
static void receive_sync_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
{
spin_lock(&ls->ls_rcom_spin);
if (!test_bit(LSFL_RCOM_WAIT, &ls->ls_flags) ||
rc_in->rc_id != ls->ls_rcom_seq) {
log_debug(ls, "reject reply %d from %d seq %llx expect %llx",
rc_in->rc_type, rc_in->rc_header.h_nodeid,
(unsigned long long)rc_in->rc_id,
(unsigned long long)ls->ls_rcom_seq);
goto out;
}
memcpy(ls->ls_recover_buf, rc_in, rc_in->rc_header.h_length);
set_bit(LSFL_RCOM_READY, &ls->ls_flags);
clear_bit(LSFL_RCOM_WAIT, &ls->ls_flags);
wake_up(&ls->ls_wait_general);
out:
spin_unlock(&ls->ls_rcom_spin);
}
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;
int max_size = dlm_config.ci_buffer_size - sizeof(struct dlm_rcom);
ls->ls_recover_nodeid = nodeid;
if (nodeid == dlm_our_nodeid()) {
ls->ls_recover_buf->rc_header.h_length =
dlm_config.ci_buffer_size;
dlm_copy_master_names(ls, last_name, last_len,
ls->ls_recover_buf->rc_buf,
max_size, 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);
allow_sync_reply(ls, &rc->rc_id);
memset(ls->ls_recover_buf, 0, dlm_config.ci_buffer_size);
send_rcom(ls, mh, rc);
error = dlm_wait_function(ls, &rcom_response);
disallow_sync_reply(ls);
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, nodeid;
nodeid = rc_in->rc_header.h_nodeid;
inlen = rc_in->rc_header.h_length - sizeof(struct dlm_rcom);
outlen = dlm_config.ci_buffer_size - sizeof(struct dlm_rcom);
error = create_rcom(ls, nodeid, DLM_RCOM_NAMES_REPLY, outlen, &rc, &mh);
if (error)
return;
rc->rc_id = rc_in->rc_id;
rc->rc_seq_reply = rc_in->rc_seq;
dlm_copy_master_names(ls, rc_in->rc_buf, inlen, rc->rc_buf, outlen,
nodeid);
send_rcom(ls, mh, rc);
}
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;
rc->rc_seq_reply = rc_in->rc_seq;
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 = cpu_to_le32(lkb->lkb_ownpid);
rl->rl_lkid = cpu_to_le32(lkb->lkb_id);
rl->rl_exflags = cpu_to_le32(lkb->lkb_exflags);
rl->rl_flags = cpu_to_le32(lkb->lkb_flags);
rl->rl_lvbseq = cpu_to_le32(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 = cpu_to_le16(lkb->lkb_wait_type);
if (lkb->lkb_bastfn)
rl->rl_asts |= DLM_CB_BAST;
if (lkb->lkb_astfn)
rl->rl_asts |= DLM_CB_CAST;
rl->rl_namelen = cpu_to_le16(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;
}
/* needs at least dlm_rcom + rcom_lock */
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;
rc->rc_seq_reply = rc_in->rc_seq;
send_rcom(ls, mh, 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. */
int dlm_send_ls_not_ready(int nodeid, struct dlm_rcom *rc_in)
{
struct dlm_rcom *rc;
struct rcom_config *rf;
struct dlm_mhandle *mh;
char *mb;
int mb_len = sizeof(struct dlm_rcom) + sizeof(struct rcom_config);
mh = dlm_lowcomms_get_buffer(nodeid, mb_len, GFP_NOFS, &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_id = rc_in->rc_id;
rc->rc_seq_reply = rc_in->rc_seq;
rc->rc_result = -ESRCH;
rf = (struct rcom_config *) rc->rc_buf;
rf->rf_lvblen = cpu_to_le32(~0U);
dlm_rcom_out(rc);
dlm_lowcomms_commit_buffer(mh);
return 0;
}
static int is_old_reply(struct dlm_ls *ls, struct dlm_rcom *rc)
{
uint64_t seq;
int rv = 0;
switch (rc->rc_type) {
case DLM_RCOM_STATUS_REPLY:
case DLM_RCOM_NAMES_REPLY:
case DLM_RCOM_LOOKUP_REPLY:
case DLM_RCOM_LOCK_REPLY:
spin_lock(&ls->ls_recover_lock);
seq = ls->ls_recover_seq;
spin_unlock(&ls->ls_recover_lock);
if (rc->rc_seq_reply != seq) {
log_debug(ls, "ignoring old reply %x from %d "
"seq_reply %llx expect %llx",
rc->rc_type, rc->rc_header.h_nodeid,
(unsigned long long)rc->rc_seq_reply,
(unsigned long long)seq);
rv = 1;
}
}
return rv;
}
/* Called by dlm_recv; corresponds to dlm_receive_message() but special
recovery-only comms are sent through here. */
void dlm_receive_rcom(struct dlm_ls *ls, struct dlm_rcom *rc, int nodeid)
{
int lock_size = sizeof(struct dlm_rcom) + sizeof(struct rcom_lock);
if (dlm_recovery_stopped(ls) && (rc->rc_type != DLM_RCOM_STATUS)) {
log_debug(ls, "ignoring recovery message %x from %d",
rc->rc_type, nodeid);
goto out;
}
if (is_old_reply(ls, rc))
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:
if (rc->rc_header.h_length < lock_size)
goto Eshort;
receive_rcom_lock(ls, rc);
break;
case DLM_RCOM_STATUS_REPLY:
receive_sync_reply(ls, rc);
break;
case DLM_RCOM_NAMES_REPLY:
receive_sync_reply(ls, rc);
break;
case DLM_RCOM_LOOKUP_REPLY:
receive_rcom_lookup_reply(ls, rc);
break;
case DLM_RCOM_LOCK_REPLY:
if (rc->rc_header.h_length < lock_size)
goto Eshort;
dlm_recover_process_copy(ls, rc);
break;
default:
log_error(ls, "receive_rcom bad type %d", rc->rc_type);
}
out:
return;
Eshort:
log_error(ls, "recovery message %x from %d is too short",
rc->rc_type, nodeid);
}