Add qdev_add_vm_change_state_handler_full() variant that allows setting a prepare callback in addition to the main callback. This will facilitate adding P2P support for VFIO migration in the following patches. Signed-off-by: Avihai Horon <avihaih@nvidia.com> Signed-off-by: Joao Martins <joao.m.martins@oracle.com> Reviewed-by: Cédric Le Goater <clg@redhat.com> Tested-by: YangHang Liu <yanghliu@redhat.com> Signed-off-by: Cédric Le Goater <clg@redhat.com>
		
			
				
	
	
		
			75 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			75 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 *  qdev vm change state handlers
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 *
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 *  This program is free software; you can redistribute it and/or modify
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 *  it under the terms of the GNU General Public License as published by
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 *  the Free Software Foundation; either version 2 of the License,
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 *  or (at your option) any later version.
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 *
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 *  This program is distributed in the hope that it will be useful,
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 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
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 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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 *  GNU General Public License for more details.
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 *
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 *  You should have received a copy of the GNU General Public License
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 *  along with this program; if not, see <http://www.gnu.org/licenses/>.
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 */
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#include "qemu/osdep.h"
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#include "hw/qdev-core.h"
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#include "sysemu/runstate.h"
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static int qdev_get_dev_tree_depth(DeviceState *dev)
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{
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    int depth;
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    for (depth = 0; dev; depth++) {
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        BusState *bus = dev->parent_bus;
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        if (!bus) {
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            break;
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        }
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        dev = bus->parent;
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    }
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    return depth;
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}
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/**
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 * qdev_add_vm_change_state_handler:
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 * @dev: the device that owns this handler
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 * @cb: the callback function to be invoked
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 * @opaque: user data passed to the callback function
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 *
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 * This function works like qemu_add_vm_change_state_handler() except callbacks
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 * are invoked in qdev tree depth order.  Ordering is desirable when callbacks
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 * of children depend on their parent's callback having completed first.
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 *
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 * For example, when qdev_add_vm_change_state_handler() is used, a host
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 * controller's callback is invoked before the children on its bus when the VM
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 * starts running.  The order is reversed when the VM stops running.
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 *
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 * Returns: an entry to be freed with qemu_del_vm_change_state_handler()
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 */
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VMChangeStateEntry *qdev_add_vm_change_state_handler(DeviceState *dev,
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                                                     VMChangeStateHandler *cb,
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                                                     void *opaque)
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{
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    return qdev_add_vm_change_state_handler_full(dev, cb, NULL, opaque);
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}
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/*
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 * Exactly like qdev_add_vm_change_state_handler() but passes a prepare_cb
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 * argument too.
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 */
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VMChangeStateEntry *qdev_add_vm_change_state_handler_full(
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    DeviceState *dev, VMChangeStateHandler *cb,
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    VMChangeStateHandler *prepare_cb, void *opaque)
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{
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    int depth = qdev_get_dev_tree_depth(dev);
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    return qemu_add_vm_change_state_handler_prio_full(cb, prepare_cb, opaque,
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                                                      depth);
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}
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