kernel-ark/fs/dlm/rcom.c
David Teigland 475f230c60 dlm: fix unlock balance warnings
The in_recovery rw_semaphore has always been acquired and
released by different threads by design.  To work around
the "BUG: bad unlock balance detected!" messages, adjust
things so the dlm_recoverd thread always does both down_write
and up_write.

Signed-off-by: David Teigland <teigland@redhat.com>
2012-08-08 11:33:49 -05:00

657 lines
16 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);
}
static void set_rcom_status(struct dlm_ls *ls, struct rcom_status *rs,
uint32_t flags)
{
rs->rs_flags = cpu_to_le32(flags);
}
/* 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 set_rcom_config(struct dlm_ls *ls, struct rcom_config *rf,
uint32_t num_slots)
{
rf->rf_lvblen = cpu_to_le32(ls->ls_lvblen);
rf->rf_lsflags = cpu_to_le32(ls->ls_exflags);
rf->rf_our_slot = cpu_to_le16(ls->ls_slot);
rf->rf_num_slots = cpu_to_le16(num_slots);
rf->rf_generation = cpu_to_le32(ls->ls_generation);
}
static int check_rcom_config(struct dlm_ls *ls, struct dlm_rcom *rc, int nodeid)
{
struct rcom_config *rf = (struct rcom_config *) rc->rc_buf;
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 (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);
}
/*
* low nodeid gathers one slot value at a time from each node.
* it sets need_slots=0, and saves rf_our_slot returned from each
* rcom_config.
*
* other nodes gather all slot values at once from the low nodeid.
* they set need_slots=1, and ignore the rf_our_slot returned from each
* rcom_config. they use the rf_num_slots returned from the low
* node's rcom_config.
*/
int dlm_rcom_status(struct dlm_ls *ls, int nodeid, uint32_t status_flags)
{
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,
sizeof(struct rcom_status), &rc, &mh);
if (error)
goto out;
set_rcom_status(ls, (struct rcom_status *)rc->rc_buf, status_flags);
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;
error = 0;
} else {
error = check_rcom_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;
struct rcom_status *rs;
uint32_t status;
int nodeid = rc_in->rc_header.h_nodeid;
int len = sizeof(struct rcom_config);
int num_slots = 0;
int error;
if (!dlm_slots_version(&rc_in->rc_header)) {
status = dlm_recover_status(ls);
goto do_create;
}
rs = (struct rcom_status *)rc_in->rc_buf;
if (!(rs->rs_flags & DLM_RSF_NEED_SLOTS)) {
status = dlm_recover_status(ls);
goto do_create;
}
spin_lock(&ls->ls_recover_lock);
status = ls->ls_recover_status;
num_slots = ls->ls_num_slots;
spin_unlock(&ls->ls_recover_lock);
len += num_slots * sizeof(struct rcom_slot);
do_create:
error = create_rcom(ls, nodeid, DLM_RCOM_STATUS_REPLY,
len, &rc, &mh);
if (error)
return;
rc->rc_id = rc_in->rc_id;
rc->rc_seq_reply = rc_in->rc_seq;
rc->rc_result = status;
set_rcom_config(ls, (struct rcom_config *)rc->rc_buf, num_slots);
if (!num_slots)
goto do_send;
spin_lock(&ls->ls_recover_lock);
if (ls->ls_num_slots != num_slots) {
spin_unlock(&ls->ls_recover_lock);
log_debug(ls, "receive_rcom_status num_slots %d to %d",
num_slots, ls->ls_num_slots);
rc->rc_result = 0;
set_rcom_config(ls, (struct rcom_config *)rc->rc_buf, 0);
goto do_send;
}
dlm_slots_copy_out(ls, rc);
spin_unlock(&ls->ls_recover_lock);
do_send:
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;
ls->ls_recover_nodeid = nodeid;
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->res_id;
send_rcom(ls, mh, rc);
out:
return error;
}
int dlm_send_rcom_lookup_dump(struct dlm_rsb *r, int to_nodeid)
{
struct dlm_rcom *rc;
struct dlm_mhandle *mh;
struct dlm_ls *ls = r->res_ls;
int error;
error = create_rcom(ls, to_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 = 0xFFFFFFFF;
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;
if (rc_in->rc_id == 0xFFFFFFFF) {
log_error(ls, "receive_rcom_lookup dump from %d", nodeid);
dlm_dump_rsb_name(ls, rc_in->rc_buf, len);
return;
}
error = dlm_master_lookup(ls, nodeid, rc_in->rc_buf, len,
DLM_LU_RECOVER_MASTER, &ret_nodeid, NULL);
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;
}
/*
* Ignore messages for stage Y before we set
* recover_status bit for stage X:
*
* recover_status = 0
*
* dlm_recover_members()
* - send nothing
* - recv nothing
* - ignore NAMES, NAMES_REPLY
* - ignore LOOKUP, LOOKUP_REPLY
* - ignore LOCK, LOCK_REPLY
*
* recover_status |= NODES
*
* dlm_recover_members_wait()
*
* dlm_recover_directory()
* - send NAMES
* - recv NAMES_REPLY
* - ignore LOOKUP, LOOKUP_REPLY
* - ignore LOCK, LOCK_REPLY
*
* recover_status |= DIR
*
* dlm_recover_directory_wait()
*
* dlm_recover_masters()
* - send LOOKUP
* - recv LOOKUP_REPLY
*
* dlm_recover_locks()
* - send LOCKS
* - recv LOCKS_REPLY
*
* recover_status |= LOCKS
*
* dlm_recover_locks_wait()
*
* recover_status |= DONE
*/
/* 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);
int stop, reply = 0, names = 0, lookup = 0, lock = 0;
uint32_t status;
uint64_t seq;
switch (rc->rc_type) {
case DLM_RCOM_STATUS_REPLY:
reply = 1;
break;
case DLM_RCOM_NAMES:
names = 1;
break;
case DLM_RCOM_NAMES_REPLY:
names = 1;
reply = 1;
break;
case DLM_RCOM_LOOKUP:
lookup = 1;
break;
case DLM_RCOM_LOOKUP_REPLY:
lookup = 1;
reply = 1;
break;
case DLM_RCOM_LOCK:
lock = 1;
break;
case DLM_RCOM_LOCK_REPLY:
lock = 1;
reply = 1;
break;
};
spin_lock(&ls->ls_recover_lock);
status = ls->ls_recover_status;
stop = test_bit(LSFL_RECOVER_STOP, &ls->ls_flags);
seq = ls->ls_recover_seq;
spin_unlock(&ls->ls_recover_lock);
if (stop && (rc->rc_type != DLM_RCOM_STATUS))
goto ignore;
if (reply && (rc->rc_seq_reply != seq))
goto ignore;
if (!(status & DLM_RS_NODES) && (names || lookup || lock))
goto ignore;
if (!(status & DLM_RS_DIR) && (lookup || lock))
goto ignore;
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);
}
return;
ignore:
log_limit(ls, "dlm_receive_rcom ignore msg %d "
"from %d %llu %llu recover seq %llu sts %x gen %u",
rc->rc_type,
nodeid,
(unsigned long long)rc->rc_seq,
(unsigned long long)rc->rc_seq_reply,
(unsigned long long)seq,
status, ls->ls_generation);
return;
Eshort:
log_error(ls, "recovery message %d from %d is too short",
rc->rc_type, nodeid);
}