int servant(const char *diskname, int mode, const void* argp)
{
struct sector_mbox_s *s_mbox = NULL;
struct sector_node_s *s_node = NULL;
struct sector_header_s *s_header = NULL;
int mbox;
int rc = 0;
time_t t0, t1, latency;
union sigval signal_value;
sigset_t servant_masks;
struct sbd_context *st;
pid_t ppid;
char uuid[37];
const struct servants_list_item *s = argp;
if (!diskname) {
cl_log(LOG_ERR, "Empty disk name %s.", diskname);
return -1;
}
cl_log(LOG_INFO, "Servant starting for device %s", diskname);
/* Block most of the signals */
sigfillset(&servant_masks);
sigdelset(&servant_masks, SIGKILL);
sigdelset(&servant_masks, SIGFPE);
sigdelset(&servant_masks, SIGILL);
sigdelset(&servant_masks, SIGSEGV);
sigdelset(&servant_masks, SIGBUS);
sigdelset(&servant_masks, SIGALRM);
/* FIXME: check error */
sigprocmask(SIG_SETMASK, &servant_masks, NULL);
atexit(servant_exit);
servant_inform_parent = 1;
st = open_device(diskname, LOG_WARNING);
if (!st) {
return -1;
}
s_header = header_get(st);
if (!s_header) {
cl_log(LOG_ERR, "Not a valid header on %s", diskname);
return -1;
}
if (servant_check_timeout_inconsistent(s_header) < 0) {
cl_log(LOG_ERR, "Timeouts on %s do not match first device",
diskname);
return -1;
}
if (s_header->minor_version > 0) {
uuid_unparse_lower(s_header->uuid, uuid);
cl_log(LOG_INFO, "Device %s uuid: %s", diskname, uuid);
}
mbox = slot_allocate(st, local_uname);
if (mbox < 0) {
cl_log(LOG_ERR,
"No slot allocated, and automatic allocation failed for disk %s.",
diskname);
rc = -1;
goto out;
}
s_node = sector_alloc();
if (slot_read(st, mbox, s_node) < 0) {
cl_log(LOG_ERR, "Unable to read node entry on %s",
diskname);
exit(1);
}
DBGLOG(LOG_INFO, "Monitoring slot %d on disk %s", mbox, diskname);
if (s_header->minor_version == 0) {
set_proc_title("sbd: watcher: %s - slot: %d", diskname, mbox);
} else {
set_proc_title("sbd: watcher: %s - slot: %d - uuid: %s",
diskname, mbox, uuid);
}
s_mbox = sector_alloc();
if (s->first_start) {
if (mode > 0) {
if (mbox_read(st, mbox, s_mbox) < 0) {
cl_log(LOG_ERR, "mbox read failed during start-up in servant.");
rc = -1;
goto out;
}
if (s_mbox->cmd != SBD_MSG_EXIT &&
s_mbox->cmd != SBD_MSG_EMPTY) {
/* Not a clean stop. Abort start-up */
cl_log(LOG_WARNING, "Found fencing message - aborting start-up. Manual intervention required!");
ppid = getppid();
sigqueue(ppid, SIG_EXITREQ, signal_value);
rc = 0;
goto out;
}
}
DBGLOG(LOG_INFO, "First servant start - zeroing inbox");
memset(s_mbox, 0, sizeof(*s_mbox));
if (mbox_write(st, mbox, s_mbox) < 0) {
rc = -1;
goto out;
}
}
memset(&signal_value, 0, sizeof(signal_value));
while (1) {
struct sector_header_s *s_header_retry = NULL;
struct sector_node_s *s_node_retry = NULL;
t0 = time(NULL);
sleep(timeout_loop);
ppid = getppid();
if (ppid == 1) {
/* Our parent died unexpectedly. Triggering
* self-fence. */
do_reset();
}
/* These attempts are, by definition, somewhat racy. If
* the device is wiped out or corrupted between here and
* us reading our mbox, there is nothing we can do about
* that. But at least we tried. */
s_header_retry = header_get(st);
if (!s_header_retry) {
cl_log(LOG_ERR, "No longer found a valid header on %s", diskname);
exit(1);
}
if (memcmp(s_header, s_header_retry, sizeof(*s_header)) != 0) {
cl_log(LOG_ERR, "Header on %s changed since start-up!", diskname);
exit(1);
}
free(s_header_retry);
s_node_retry = sector_alloc();
if (slot_read(st, mbox, s_node_retry) < 0) {
cl_log(LOG_ERR, "slot read failed in servant.");
exit(1);
}
if (memcmp(s_node, s_node_retry, sizeof(*s_node)) != 0) {
cl_log(LOG_ERR, "Node entry on %s changed since start-up!", diskname);
exit(1);
}
free(s_node_retry);
if (mbox_read(st, mbox, s_mbox) < 0) {
cl_log(LOG_ERR, "mbox read failed in servant.");
exit(1);
}
if (s_mbox->cmd > 0) {
cl_log(LOG_INFO,
"Received command %s from %s on disk %s",
char2cmd(s_mbox->cmd), s_mbox->from, diskname);
switch (s_mbox->cmd) {
case SBD_MSG_TEST:
memset(s_mbox, 0, sizeof(*s_mbox));
mbox_write(st, mbox, s_mbox);
sigqueue(ppid, SIG_TEST, signal_value);
break;
case SBD_MSG_RESET:
do_reset();
break;
case SBD_MSG_OFF:
do_off();
break;
case SBD_MSG_EXIT:
sigqueue(ppid, SIG_EXITREQ, signal_value);
break;
case SBD_MSG_CRASHDUMP:
do_crashdump();
break;
default:
/* FIXME:
An "unknown" message might result
from a partial write.
log it and clear the slot.
*/
cl_log(LOG_ERR, "Unknown message on disk %s",
diskname);
memset(s_mbox, 0, sizeof(*s_mbox));
mbox_write(st, mbox, s_mbox);
break;
}
}
sigqueue(ppid, SIG_LIVENESS, signal_value);
t1 = time(NULL);
latency = t1 - t0;
if (timeout_watchdog_warn && (latency > timeout_watchdog_warn)) {
cl_log(LOG_WARNING,
"Latency: %d exceeded threshold %d on disk %s",
(int)latency, (int)timeout_watchdog_warn,
diskname);
} else if (debug) {
DBGLOG(LOG_INFO, "Latency: %d on disk %s", (int)latency,
diskname);
}
}
out:
free(s_mbox);
close_device(st);
if (rc == 0) {
servant_inform_parent = 0;
}
return rc;
}
/*
** This function must a send reply from at least one node, otherwise
** the requesting fence_virtd will block forever in wait_cpt_reply.
*/
static void
do_real_work(void *data, size_t len, uint32_t nodeid, uint32_t seqno)
{
struct cpg_info *info = cpg_virt_handle;
struct cpg_fence_req *req = data;
struct cpg_fence_req reply;
int reply_code = -1;
virt_state_t *vs = NULL;
int cur_state;
uint32_t cur_owner = 0;
int local = 0;
uint32_t my_id, high_id;
dbg_printf(2, "Request %d for VM %s\n", req->request, req->vm_name);
if (cpg_get_ids(&my_id, &high_id) == -1) {
syslog(LOG_WARNING, "Unable to get CPG IDs");
printf("Should never happen: Can't get CPG node ids - can't proceed\n");
return;
}
memcpy(&reply, req, sizeof(reply));
pthread_mutex_lock(&local_vm_list_lock);
update_local_vms(info);
if (strlen(req->vm_name)) {
if (use_uuid)
vs = vl_find_uuid(local_vm_list, req->vm_name);
else
vs = vl_find_name(local_vm_list, req->vm_name);
if (vs) {
local = 1;
cur_owner = vs->v_state.s_owner;
cur_state = vs->v_state.s_state;
dbg_printf(2, "Found VM %s locally state %d\n",
req->vm_name, cur_state);
}
}
pthread_mutex_unlock(&local_vm_list_lock);
if (vs == NULL) {
pthread_mutex_lock(&remote_vm_list_lock);
if (strlen(req->vm_name)) {
if (use_uuid)
vs = vl_find_uuid(remote_vm_list, req->vm_name);
else
vs = vl_find_name(remote_vm_list, req->vm_name);
if (vs) {
cur_owner = vs->v_state.s_owner;
cur_state = vs->v_state.s_state;
dbg_printf(2, "Found VM %s remotely on %u state %d\n",
req->vm_name, cur_owner, cur_state);
}
}
pthread_mutex_unlock(&remote_vm_list_lock);
}
if (!vs) {
/*
** We know about all domains on all nodes in the CPG group.
** If we didn't find it, and we're high ID, act on the request.
** We can safely assume the VM is OFF because it wasn't found
** on any current members of the CPG group.
*/
if (my_id == high_id) {
if (req->request == FENCE_STATUS)
reply_code = RESP_OFF;
else if (req->request == FENCE_OFF || req->request == FENCE_REBOOT)
reply_code = RESP_SUCCESS;
else
reply_code = 1;
dbg_printf(2, "Acting on request %d for unknown domain %s -> %d\n",
req->request, req->vm_name, reply_code);
goto out;
}
dbg_printf(2, "Not acting on request %d for unknown domain %s\n",
req->request, req->vm_name);
return;
}
if (local) {
if (req->request == FENCE_STATUS) {
/* We already have the status */
if (cur_state == VIR_DOMAIN_SHUTOFF)
reply_code = RESP_OFF;
else
reply_code = RESP_SUCCESS;
} else if (req->request == FENCE_OFF) {
reply_code = do_off(info, req->vm_name);
} else if (req->request == FENCE_ON) {
reply_code = do_on(info, req->vm_name);
} else if (req->request == FENCE_REBOOT) {
reply_code = do_reboot(info, req->vm_name);
} else {
dbg_printf(2, "Not explicitly handling request type %d for %s\n",
req->request, req->vm_name);
reply_code = 0;
}
goto out;
}
/*
** This is a request for a non-local domain that exists on a
** current CPG group member, so that member will see the request
** and act on it. We don't need to do anything.
*/
dbg_printf(2, "Nothing to do for non-local domain %s seq %d owner %u\n",
req->vm_name, seqno, cur_owner);
return;
out:
dbg_printf(2, "[%s] sending reply code seq %d -> %d\n",
req->vm_name, seqno, reply_code);
reply.response = reply_code;
if (cpg_send_reply(&reply, sizeof(reply), nodeid, seqno) < 0) {
dbg_printf(2, "cpg_send_reply failed for %s [%d %d]: %s\n",
req->vm_name, nodeid, seqno, strerror(errno));
}
}
