7  * Copyright (c) 2004-2009 Silicon Graphics, Inc.  All Rights Reserved.
11  * Cross Partition Communication (XPC) support - standard version.
29  *	  . Currently on sn2, we have no way to determine which nasid an IRQ
130 /* non-zero if any remote partition disengage was timed out */
137 /* IRQ handler notifies this wait queue on receipt of an IRQ */
164  * Timer function to enforce the timelimit on the partition disengage.
171 	DBUG_ON(time_is_after_jiffies(part->disengage_timeout));  in xpc_timeout_partition_disengage()
175 	DBUG_ON(part->disengage_timeout != 0);  in xpc_timeout_partition_disengage()
232 		if (part->act_state == XPC_P_AS_INACTIVE ||  in xpc_check_remote_hb()
233 		    part->act_state == XPC_P_AS_DEACTIVATING) {  in xpc_check_remote_hb()
256 	/* set our heartbeating to other partitions into motion */  in xpc_hb_checker()
264 			(int)(xpc_hb_check_timeout - jiffies),  in xpc_hb_checker()
303  * based on info provided by SAL. This new thread is short lived and
320  * created by XPC HB with which it calls xpc_activating(). XPC hangs on to
333 	while (part->act_state != XPC_P_AS_DEACTIVATING ||  in xpc_channel_mgr()
334 	       atomic_read(&part->nchannels_active) > 0 ||  in xpc_channel_mgr()
350 		 * wake him up.  in xpc_channel_mgr()
352 		atomic_dec(&part->channel_mgr_requests);  in xpc_channel_mgr()
353 		(void)wait_event_interruptible(part->channel_mgr_wq,  in xpc_channel_mgr()
354 				(atomic_read(&part->channel_mgr_requests) > 0 ||  in xpc_channel_mgr()
355 				 part->chctl.all_flags != 0 ||  in xpc_channel_mgr()
356 				 (part->act_state == XPC_P_AS_DEACTIVATING &&  in xpc_channel_mgr()
357 				 atomic_read(&part->nchannels_active) == 0 &&  in xpc_channel_mgr()
359 		atomic_set(&part->channel_mgr_requests, 1);  in xpc_channel_mgr()
403 	DBUG_ON(part->channels != NULL);  in xpc_setup_ch_structures()
404 	part->channels = kcalloc(XPC_MAX_NCHANNELS,  in xpc_setup_ch_structures()
407 	if (part->channels == NULL) {  in xpc_setup_ch_structures()
414 	part->remote_openclose_args =  in xpc_setup_ch_structures()
416 					  GFP_KERNEL, &part->  in xpc_setup_ch_structures()
418 	if (part->remote_openclose_args == NULL) {  in xpc_setup_ch_structures()
424 	part->chctl.all_flags = 0;  in xpc_setup_ch_structures()
425 	spin_lock_init(&part->chctl_lock);  in xpc_setup_ch_structures()
427 	atomic_set(&part->channel_mgr_requests, 1);  in xpc_setup_ch_structures()
428 	init_waitqueue_head(&part->channel_mgr_wq);  in xpc_setup_ch_structures()
430 	part->nchannels = XPC_MAX_NCHANNELS;  in xpc_setup_ch_structures()
432 	atomic_set(&part->nchannels_active, 0);  in xpc_setup_ch_structures()
433 	atomic_set(&part->nchannels_engaged, 0);  in xpc_setup_ch_structures()
435 	for (ch_number = 0; ch_number < part->nchannels; ch_number++) {  in xpc_setup_ch_structures()
436 		ch = &part->channels[ch_number];  in xpc_setup_ch_structures()
438 		ch->partid = partid;  in xpc_setup_ch_structures()
439 		ch->number = ch_number;  in xpc_setup_ch_structures()
440 		ch->flags = XPC_C_DISCONNECTED;  in xpc_setup_ch_structures()
442 		atomic_set(&ch->kthreads_assigned, 0);  in xpc_setup_ch_structures()
443 		atomic_set(&ch->kthreads_idle, 0);  in xpc_setup_ch_structures()
444 		atomic_set(&ch->kthreads_active, 0);  in xpc_setup_ch_structures()
446 		atomic_set(&ch->references, 0);  in xpc_setup_ch_structures()
447 		atomic_set(&ch->n_to_notify, 0);  in xpc_setup_ch_structures()
449 		spin_lock_init(&ch->lock);  in xpc_setup_ch_structures()
450 		init_completion(&ch->wdisconnect_wait);  in xpc_setup_ch_structures()
452 		atomic_set(&ch->n_on_msg_allocate_wq, 0);  in xpc_setup_ch_structures()
453 		init_waitqueue_head(&ch->msg_allocate_wq);  in xpc_setup_ch_structures()
454 		init_waitqueue_head(&ch->idle_wq);  in xpc_setup_ch_structures()
465 	part->setup_state = XPC_P_SS_SETUP;  in xpc_setup_ch_structures()
471 	kfree(part->remote_openclose_args_base);  in xpc_setup_ch_structures()
472 	part->remote_openclose_args = NULL;  in xpc_setup_ch_structures()
474 	kfree(part->channels);  in xpc_setup_ch_structures()
475 	part->channels = NULL;  in xpc_setup_ch_structures()
486 	DBUG_ON(atomic_read(&part->nchannels_engaged) != 0);  in xpc_teardown_ch_structures()
487 	DBUG_ON(atomic_read(&part->nchannels_active) != 0);  in xpc_teardown_ch_structures()
494 	DBUG_ON(part->setup_state != XPC_P_SS_SETUP);  in xpc_teardown_ch_structures()
495 	part->setup_state = XPC_P_SS_WTEARDOWN;  in xpc_teardown_ch_structures()
497 	wait_event(part->teardown_wq, (atomic_read(&part->references) == 0));  in xpc_teardown_ch_structures()
503 	kfree(part->remote_openclose_args_base);  in xpc_teardown_ch_structures()
504 	part->remote_openclose_args = NULL;  in xpc_teardown_ch_structures()
505 	kfree(part->channels);  in xpc_teardown_ch_structures()
506 	part->channels = NULL;  in xpc_teardown_ch_structures()
508 	part->setup_state = XPC_P_SS_TORNDOWN;  in xpc_teardown_ch_structures()
531 	spin_lock_irqsave(&part->act_lock, irq_flags);  in xpc_activating()
533 	if (part->act_state == XPC_P_AS_DEACTIVATING) {  in xpc_activating()
534 		part->act_state = XPC_P_AS_INACTIVE;  in xpc_activating()
535 		spin_unlock_irqrestore(&part->act_lock, irq_flags);  in xpc_activating()
536 		part->remote_rp_pa = 0;  in xpc_activating()
541 	DBUG_ON(part->act_state != XPC_P_AS_ACTIVATION_REQ);  in xpc_activating()
542 	part->act_state = XPC_P_AS_ACTIVATING;  in xpc_activating()
545 	spin_unlock_irqrestore(&part->act_lock, irq_flags);  in xpc_activating()
567 	if (part->reason == xpReactivating) {  in xpc_activating()
582 	spin_lock_irqsave(&part->act_lock, irq_flags);  in xpc_activate_partition()
584 	DBUG_ON(part->act_state != XPC_P_AS_INACTIVE);  in xpc_activate_partition()
586 	part->act_state = XPC_P_AS_ACTIVATION_REQ;  in xpc_activate_partition()
589 	spin_unlock_irqrestore(&part->act_lock, irq_flags);  in xpc_activate_partition()
594 		spin_lock_irqsave(&part->act_lock, irq_flags);  in xpc_activate_partition()
595 		part->act_state = XPC_P_AS_INACTIVE;  in xpc_activate_partition()
597 		spin_unlock_irqrestore(&part->act_lock, irq_flags);  in xpc_activate_partition()
604 	int idle = atomic_read(&ch->kthreads_idle);  in xpc_activate_kthreads()
605 	int assigned = atomic_read(&ch->kthreads_assigned);  in xpc_activate_kthreads()
612 		needed -= wakeup;  in xpc_activate_kthreads()
615 			"channel=%d\n", wakeup, ch->partid, ch->number);  in xpc_activate_kthreads()
618 		wake_up_nr(&ch->idle_wq, wakeup);  in xpc_activate_kthreads()
624 	if (needed + assigned > ch->kthreads_assigned_limit) {  in xpc_activate_kthreads()
625 		needed = ch->kthreads_assigned_limit - assigned;  in xpc_activate_kthreads()
631 		needed, ch->partid, ch->number);  in xpc_activate_kthreads()
649 		       !(ch->flags & XPC_C_DISCONNECTING)) {  in xpc_kthread_waitmsgs()
653 		if (atomic_inc_return(&ch->kthreads_idle) >  in xpc_kthread_waitmsgs()
654 		    ch->kthreads_idle_limit) {  in xpc_kthread_waitmsgs()
655 			/* too many idle kthreads on this channel */  in xpc_kthread_waitmsgs()
656 			atomic_dec(&ch->kthreads_idle);  in xpc_kthread_waitmsgs()
663 		(void)wait_event_interruptible_exclusive(ch->idle_wq,  in xpc_kthread_waitmsgs()
665 				 (ch->flags & XPC_C_DISCONNECTING)));  in xpc_kthread_waitmsgs()
667 		atomic_dec(&ch->kthreads_idle);  in xpc_kthread_waitmsgs()
669 	} while (!(ch->flags & XPC_C_DISCONNECTING));  in xpc_kthread_waitmsgs()
687 	ch = &part->channels[ch_number];  in xpc_kthread_start()
689 	if (!(ch->flags & XPC_C_DISCONNECTING)) {  in xpc_kthread_start()
693 		spin_lock_irqsave(&ch->lock, irq_flags);  in xpc_kthread_start()
694 		if (!(ch->flags & XPC_C_CONNECTEDCALLOUT)) {  in xpc_kthread_start()
695 			ch->flags |= XPC_C_CONNECTEDCALLOUT;  in xpc_kthread_start()
696 			spin_unlock_irqrestore(&ch->lock, irq_flags);  in xpc_kthread_start()
700 			spin_lock_irqsave(&ch->lock, irq_flags);  in xpc_kthread_start()
701 			ch->flags |= XPC_C_CONNECTEDCALLOUT_MADE;  in xpc_kthread_start()
702 			spin_unlock_irqrestore(&ch->lock, irq_flags);  in xpc_kthread_start()
711 			n_needed = n_of_deliverable_payloads(ch) - 1;  in xpc_kthread_start()
712 			if (n_needed > 0 && !(ch->flags & XPC_C_DISCONNECTING))  in xpc_kthread_start()
716 			spin_unlock_irqrestore(&ch->lock, irq_flags);  in xpc_kthread_start()
724 	spin_lock_irqsave(&ch->lock, irq_flags);  in xpc_kthread_start()
725 	if ((ch->flags & XPC_C_CONNECTEDCALLOUT_MADE) &&  in xpc_kthread_start()
726 	    !(ch->flags & XPC_C_DISCONNECTINGCALLOUT)) {  in xpc_kthread_start()
727 		ch->flags |= XPC_C_DISCONNECTINGCALLOUT;  in xpc_kthread_start()
728 		spin_unlock_irqrestore(&ch->lock, irq_flags);  in xpc_kthread_start()
732 		spin_lock_irqsave(&ch->lock, irq_flags);  in xpc_kthread_start()
733 		ch->flags |= XPC_C_DISCONNECTINGCALLOUT_MADE;  in xpc_kthread_start()
735 	spin_unlock_irqrestore(&ch->lock, irq_flags);  in xpc_kthread_start()
737 	if (atomic_dec_return(&ch->kthreads_assigned) == 0 &&  in xpc_kthread_start()
738 	    atomic_dec_return(&part->nchannels_engaged) == 0) {  in xpc_kthread_start()
768 	u64 args = XPC_PACK_ARGS(ch->partid, ch->number);  in xpc_create_kthreads()
769 	struct xpc_partition *part = &xpc_partitions[ch->partid];  in xpc_create_kthreads()
774 	while (needed-- > 0) {  in xpc_create_kthreads()
777 		 * The following is done on behalf of the newly created  in xpc_create_kthreads()
782 			if (!atomic_inc_not_zero(&ch->kthreads_assigned)) {  in xpc_create_kthreads()
784 				BUG_ON(!(ch->flags &  in xpc_create_kthreads()
789 		} else if (ch->flags & XPC_C_DISCONNECTING) {  in xpc_create_kthreads()
792 		} else if (atomic_inc_return(&ch->kthreads_assigned) == 1 &&  in xpc_create_kthreads()
793 			   atomic_inc_return(&part->nchannels_engaged) == 1) {  in xpc_create_kthreads()
800 				      "xpc%02dc%d", ch->partid, ch->number);  in xpc_create_kthreads()
806 			 * !(ch->flags & XPC_C_DISCONNECTINGCALLOUT)) is true,  in xpc_create_kthreads()
814 			if (atomic_dec_return(&ch->kthreads_assigned) == 0 &&  in xpc_create_kthreads()
815 			    atomic_dec_return(&part->nchannels_engaged) == 0) {  in xpc_create_kthreads()
821 			if (atomic_read(&ch->kthreads_assigned) <  in xpc_create_kthreads()
822 			    ch->kthreads_idle_limit) {  in xpc_create_kthreads()
828 				spin_lock_irqsave(&ch->lock, irq_flags);  in xpc_create_kthreads()
831 				spin_unlock_irqrestore(&ch->lock, irq_flags);  in xpc_create_kthreads()
854 		ch = &part->channels[ch_number];  in xpc_disconnect_wait()
856 		if (!(ch->flags & XPC_C_WDISCONNECT)) {  in xpc_disconnect_wait()
861 		wait_for_completion(&ch->wdisconnect_wait);  in xpc_disconnect_wait()
863 		spin_lock_irqsave(&ch->lock, irq_flags);  in xpc_disconnect_wait()
864 		DBUG_ON(!(ch->flags & XPC_C_DISCONNECTED));  in xpc_disconnect_wait()
867 		if (ch->delayed_chctl_flags) {  in xpc_disconnect_wait()
868 			if (part->act_state != XPC_P_AS_DEACTIVATING) {  in xpc_disconnect_wait()
869 				spin_lock(&part->chctl_lock);  in xpc_disconnect_wait()
870 				part->chctl.flags[ch->number] |=  in xpc_disconnect_wait()
871 				    ch->delayed_chctl_flags;  in xpc_disconnect_wait()
872 				spin_unlock(&part->chctl_lock);  in xpc_disconnect_wait()
875 			ch->delayed_chctl_flags = 0;  in xpc_disconnect_wait()
878 		ch->flags &= ~XPC_C_WDISCONNECT;  in xpc_disconnect_wait()
879 		spin_unlock_irqrestore(&ch->lock, irq_flags);  in xpc_disconnect_wait()
899 		return -ENOMEM;  in xpc_setup_partitions()
915 		part->activate_IRQ_rcvd = 0;  in xpc_setup_partitions()
916 		spin_lock_init(&part->act_lock);  in xpc_setup_partitions()
917 		part->act_state = XPC_P_AS_INACTIVE;  in xpc_setup_partitions()
920 		timer_setup(&part->disengage_timer,  in xpc_setup_partitions()
923 		part->setup_state = XPC_P_SS_UNSET;  in xpc_setup_partitions()
924 		init_waitqueue_head(&part->teardown_wq);  in xpc_setup_partitions()
925 		atomic_set(&part->references, 0);  in xpc_setup_partitions()
951 	 * (if one is running) know that they should exit. Also wake up  in xpc_do_exit()
978 			    part->act_state == XPC_P_AS_INACTIVE) {  in xpc_do_exit()
986 			if (part->disengage_timeout > disengage_timeout)  in xpc_do_exit()
987 				disengage_timeout = part->disengage_timeout;  in xpc_do_exit()
994 					 "%ld seconds\n", (disengage_timeout -  in xpc_do_exit()
1098 		    part->act_state != XPC_P_AS_INACTIVE) {  in xpc_die_deactivate()
1109 	 * Given that one iteration through the following while-loop takes  in xpc_die_deactivate()
1123 		if (!keep_waiting--) {  in xpc_die_deactivate()
1135 		if (!wait_to_print--) {  in xpc_die_deactivate()
1192 		if (die_args->trapnr == X86_TRAP_DF)  in xpc_system_die()
1195 		if (((die_args->trapnr == X86_TRAP_MF) ||  in xpc_system_die()
1196 		     (die_args->trapnr == X86_TRAP_XF)) &&  in xpc_system_die()
1197 		    !user_mode(die_args->regs))  in xpc_system_die()
1227 		ret = -ENODEV;  in xpc_init()
1264 	 * The real work-horse behind xpc.  This processes incoming  in xpc_init()
1270 		ret = -EBUSY;  in xpc_init()
1276 	 * activate based on info provided by SAL. This new thread is short  in xpc_init()
1284 		/* mark this new thread as a non-starter */  in xpc_init()
1288 		return -EBUSY;  in xpc_init()