/*
* Timer function to enforce the timelimit on the partition disengage.
*/
static void
xpc_timeout_partition_disengage(unsigned long data)
{
struct xpc_partition *part = (struct xpc_partition *)data;
DBUG_ON(time_is_after_jiffies(part->disengage_timeout));
(void)xpc_partition_disengaged(part);
DBUG_ON(part->disengage_timeout != 0);
DBUG_ON(xpc_partition_engaged(XPC_PARTID(part)));
}
/*
* Timer function to enforce the timelimit on the partition disengage request.
*/
static void
xpc_timeout_partition_disengage_request(unsigned long data)
{
struct xpc_partition *part = (struct xpc_partition *)data;
DBUG_ON(time_before(jiffies, part->disengage_request_timeout));
(void)xpc_partition_disengaged(part);
DBUG_ON(part->disengage_request_timeout != 0);
DBUG_ON(xpc_partition_engaged(1UL << XPC_PARTID(part)) != 0);
}
/*
* See if the other side has responded to a partition deactivate request
* from us. Though we requested the remote partition to deactivate with regard
* to us, we really only need to wait for the other side to disengage from us.
*/
int
xpc_partition_disengaged(struct xpc_partition *part)
{
short partid = XPC_PARTID(part);
int disengaged;
disengaged = !xpc_partition_engaged(partid);
if (part->disengage_timeout) {
if (!disengaged) {
if (time_is_after_jiffies(part->disengage_timeout)) {
/* timelimit hasn't been reached yet */
return 0;
}
/*
* Other side hasn't responded to our deactivate
* request in a timely fashion, so assume it's dead.
*/
dev_info(xpc_part, "deactivate request to remote "
"partition %d timed out\n", partid);
xpc_disengage_timedout = 1;
xpc_assume_partition_disengaged(partid);
disengaged = 1;
}
part->disengage_timeout = 0;
/* cancel the timer function, provided it's not us */
if (!in_interrupt())
del_singleshot_timer_sync(&part->disengage_timer);
DBUG_ON(part->act_state != XPC_P_AS_DEACTIVATING &&
part->act_state != XPC_P_AS_INACTIVE);
if (part->act_state != XPC_P_AS_INACTIVE)
xpc_wakeup_channel_mgr(part);
xpc_cancel_partition_deactivation_request(part);
}
return disengaged;
}
/*
* spin_lock_irqsave() is expected to be held on entry.
*/
static void
xpc_process_disconnect(struct xpc_channel *ch, unsigned long *irq_flags)
{
struct xpc_partition *part = &xpc_partitions[ch->partid];
u32 channel_was_connected = (ch->flags & XPC_C_WASCONNECTED);
DBUG_ON(!spin_is_locked(&ch->lock));
if (!(ch->flags & XPC_C_DISCONNECTING))
return;
DBUG_ON(!(ch->flags & XPC_C_CLOSEREQUEST));
/* make sure all activity has settled down first */
if (atomic_read(&ch->kthreads_assigned) > 0 ||
atomic_read(&ch->references) > 0) {
return;
}
DBUG_ON((ch->flags & XPC_C_CONNECTEDCALLOUT_MADE) &&
!(ch->flags & XPC_C_DISCONNECTINGCALLOUT_MADE));
if (part->act_state == XPC_P_AS_DEACTIVATING) {
/* can't proceed until the other side disengages from us */
if (xpc_partition_engaged(ch->partid))
return;
} else {
/* as long as the other side is up do the full protocol */
if (!(ch->flags & XPC_C_RCLOSEREQUEST))
return;
if (!(ch->flags & XPC_C_CLOSEREPLY)) {
ch->flags |= XPC_C_CLOSEREPLY;
xpc_send_chctl_closereply(ch, irq_flags);
}
if (!(ch->flags & XPC_C_RCLOSEREPLY))
return;
}
/* wake those waiting for notify completion */
if (atomic_read(&ch->n_to_notify) > 0) {
/* we do callout while holding ch->lock, callout can't block */
xpc_notify_senders_of_disconnect(ch);
}
/* both sides are disconnected now */
if (ch->flags & XPC_C_DISCONNECTINGCALLOUT_MADE) {
spin_unlock_irqrestore(&ch->lock, *irq_flags);
xpc_disconnect_callout(ch, xpDisconnected);
spin_lock_irqsave(&ch->lock, *irq_flags);
}
DBUG_ON(atomic_read(&ch->n_to_notify) != 0);
/* it's now safe to free the channel's message queues */
xpc_teardown_msg_structures(ch);
ch->func = NULL;
ch->key = NULL;
ch->entry_size = 0;
ch->local_nentries = 0;
ch->remote_nentries = 0;
ch->kthreads_assigned_limit = 0;
ch->kthreads_idle_limit = 0;
/*
* Mark the channel disconnected and clear all other flags, including
* XPC_C_SETUP (because of call to xpc_teardown_msg_structures()) but
* not including XPC_C_WDISCONNECT (if it was set).
*/
ch->flags = (XPC_C_DISCONNECTED | (ch->flags & XPC_C_WDISCONNECT));
atomic_dec(&part->nchannels_active);
if (channel_was_connected) {
dev_info(xpc_chan, "channel %d to partition %d disconnected, "
"reason=%d\n", ch->number, ch->partid, ch->reason);
}
if (ch->flags & XPC_C_WDISCONNECT) {
/* we won't lose the CPU since we're holding ch->lock */
complete(&ch->wdisconnect_wait);
} else if (ch->delayed_chctl_flags) {
if (part->act_state != XPC_P_AS_DEACTIVATING) {
/* time to take action on any delayed chctl flags */
spin_lock(&part->chctl_lock);
part->chctl.flags[ch->number] |=
ch->delayed_chctl_flags;
spin_unlock(&part->chctl_lock);
}
ch->delayed_chctl_flags = 0;
}
}
/*
* Notify other partitions to deactivate from us by first disengaging from all
* references to our memory.
*/
static void
xpc_die_deactivate(void)
{
struct xpc_partition *part;
short partid;
int any_engaged;
long keep_waiting;
long wait_to_print;
/* keep xpc_hb_checker thread from doing anything (just in case) */
xpc_exiting = 1;
xpc_disallow_all_hbs(); /*indicate we're deactivated */
for (partid = 0; partid < xp_max_npartitions; partid++) {
part = &xpc_partitions[partid];
if (xpc_partition_engaged(partid) ||
part->act_state != XPC_P_AS_INACTIVE) {
xpc_request_partition_deactivation(part);
xpc_indicate_partition_disengaged(part);
}
}
/*
* Though we requested that all other partitions deactivate from us,
* we only wait until they've all disengaged or we've reached the
* defined timelimit.
*
* Given that one iteration through the following while-loop takes
* approximately 200 microseconds, calculate the #of loops to take
* before bailing and the #of loops before printing a waiting message.
*/
keep_waiting = xpc_disengage_timelimit * 1000 * 5;
wait_to_print = XPC_DEACTIVATE_PRINTMSG_INTERVAL * 1000 * 5;
while (1) {
any_engaged = xpc_any_partition_engaged();
if (!any_engaged) {
dev_info(xpc_part, "all partitions have deactivated\n");
break;
}
if (!keep_waiting--) {
for (partid = 0; partid < xp_max_npartitions;
partid++) {
if (xpc_partition_engaged(partid)) {
dev_info(xpc_part, "deactivate from "
"remote partition %d timed "
"out\n", partid);
}
}
break;
}
if (!wait_to_print--) {
dev_info(xpc_part, "waiting for remote partitions to "
"deactivate, timeout in %ld seconds\n",
keep_waiting / (1000 * 5));
wait_to_print = XPC_DEACTIVATE_PRINTMSG_INTERVAL *
1000 * 5;
}
udelay(200);
}
}
static void
xpc_do_exit(enum xp_retval reason)
{
short partid;
int active_part_count, printed_waiting_msg = 0;
struct xpc_partition *part;
unsigned long printmsg_time, disengage_request_timeout = 0;
/* a 'rmmod XPC' and a 'reboot' cannot both end up here together */
DBUG_ON(xpc_exiting == 1);
/*
* Let the heartbeat checker thread and the discovery thread
* (if one is running) know that they should exit. Also wake up
* the heartbeat checker thread in case it's sleeping.
*/
xpc_exiting = 1;
wake_up_interruptible(&xpc_act_IRQ_wq);
/* ignore all incoming interrupts */
free_irq(SGI_XPC_ACTIVATE, NULL);
/* wait for the discovery thread to exit */
wait_for_completion(&xpc_discovery_exited);
/* wait for the heartbeat checker thread to exit */
wait_for_completion(&xpc_hb_checker_exited);
/* sleep for a 1/3 of a second or so */
(void)msleep_interruptible(300);
/* wait for all partitions to become inactive */
printmsg_time = jiffies + (XPC_DISENGAGE_PRINTMSG_INTERVAL * HZ);
xpc_disengage_request_timedout = 0;
do {
active_part_count = 0;
for (partid = 1; partid < XP_MAX_PARTITIONS; partid++) {
part = &xpc_partitions[partid];
if (xpc_partition_disengaged(part) &&
part->act_state == XPC_P_INACTIVE) {
continue;
}
active_part_count++;
XPC_DEACTIVATE_PARTITION(part, reason);
if (part->disengage_request_timeout >
disengage_request_timeout) {
disengage_request_timeout =
part->disengage_request_timeout;
}
}
if (xpc_partition_engaged(-1UL)) {
if (time_after(jiffies, printmsg_time)) {
dev_info(xpc_part, "waiting for remote "
"partitions to disengage, timeout in "
"%ld seconds\n",
(disengage_request_timeout - jiffies)
/ HZ);
printmsg_time = jiffies +
(XPC_DISENGAGE_PRINTMSG_INTERVAL * HZ);
printed_waiting_msg = 1;
}
} else if (active_part_count > 0) {
if (printed_waiting_msg) {
dev_info(xpc_part, "waiting for local partition"
" to disengage\n");
printed_waiting_msg = 0;
}
} else {
if (!xpc_disengage_request_timedout) {
dev_info(xpc_part, "all partitions have "
"disengaged\n");
}
break;
}
/* sleep for a 1/3 of a second or so */
(void)msleep_interruptible(300);
} while (1);
DBUG_ON(xpc_partition_engaged(-1UL));
/* indicate to others that our reserved page is uninitialized */
xpc_rsvd_page->vars_pa = 0;
/* now it's time to eliminate our heartbeat */
del_timer_sync(&xpc_hb_timer);
DBUG_ON(xpc_vars->heartbeating_to_mask != 0);
if (reason == xpUnloading) {
/* take ourselves off of the reboot_notifier_list */
(void)unregister_reboot_notifier(&xpc_reboot_notifier);
/* take ourselves off of the die_notifier list */
(void)unregister_die_notifier(&xpc_die_notifier);
}
/* close down protections for IPI operations */
xpc_restrict_IPI_ops();
/* clear the interface to XPC's functions */
xpc_clear_interface();
if (xpc_sysctl)
unregister_sysctl_table(xpc_sysctl);
kfree(xpc_remote_copy_buffer_base);
}
/*
* Notify other partitions to disengage from all references to our memory.
*/
static void
xpc_die_disengage(void)
{
struct xpc_partition *part;
short partid;
unsigned long engaged;
long time, printmsg_time, disengage_request_timeout;
/* keep xpc_hb_checker thread from doing anything (just in case) */
xpc_exiting = 1;
xpc_vars->heartbeating_to_mask = 0; /* indicate we're deactivated */
for (partid = 1; partid < XP_MAX_PARTITIONS; partid++) {
part = &xpc_partitions[partid];
if (!XPC_SUPPORTS_DISENGAGE_REQUEST(part->
remote_vars_version)) {
/* just in case it was left set by an earlier XPC */
xpc_clear_partition_engaged(1UL << partid);
continue;
}
if (xpc_partition_engaged(1UL << partid) ||
part->act_state != XPC_P_INACTIVE) {
xpc_request_partition_disengage(part);
xpc_mark_partition_disengaged(part);
xpc_IPI_send_disengage(part);
}
}
time = rtc_time();
printmsg_time = time +
(XPC_DISENGAGE_PRINTMSG_INTERVAL * sn_rtc_cycles_per_second);
disengage_request_timeout = time +
(xpc_disengage_request_timelimit * sn_rtc_cycles_per_second);
/* wait for all other partitions to disengage from us */
while (1) {
engaged = xpc_partition_engaged(-1UL);
if (!engaged) {
dev_info(xpc_part, "all partitions have disengaged\n");
break;
}
time = rtc_time();
if (time >= disengage_request_timeout) {
for (partid = 1; partid < XP_MAX_PARTITIONS; partid++) {
if (engaged & (1UL << partid)) {
dev_info(xpc_part, "disengage from "
"remote partition %d timed "
"out\n", partid);
}
}
break;
}
if (time >= printmsg_time) {
dev_info(xpc_part, "waiting for remote partitions to "
"disengage, timeout in %ld seconds\n",
(disengage_request_timeout - time) /
sn_rtc_cycles_per_second);
printmsg_time = time +
(XPC_DISENGAGE_PRINTMSG_INTERVAL *
sn_rtc_cycles_per_second);
}
}
}
