..and use for both virtio-user-blk and virtio-user-gpio. This avoids the circular close by deferring shutdown due to disconnection until a later point. virtio-user-blk already had this mechanism in place so generalise it as a vhost-user helper function and use for both blk and gpio devices. While we are at it we also fix up vhost-user-gpio to re-establish the event handler after close down so we can reconnect later. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com> Message-Id: <20221130112439.2527228-5-alex.bennee@linaro.org> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
		
			
				
	
	
		
			90 lines
		
	
	
		
			2.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			90 lines
		
	
	
		
			2.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 * Copyright (c) 2017-2018 Intel Corporation
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 *
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 * This work is licensed under the terms of the GNU GPL, version 2.
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 * See the COPYING file in the top-level directory.
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 */
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#ifndef HW_VIRTIO_VHOST_USER_H
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#define HW_VIRTIO_VHOST_USER_H
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#include "chardev/char-fe.h"
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#include "hw/virtio/virtio.h"
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/**
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 * VhostUserHostNotifier - notifier information for one queue
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 * @rcu: rcu_head for cleanup
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 * @mr: memory region of notifier
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 * @addr: current mapped address
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 * @unmap_addr: address to be un-mapped
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 * @idx: virtioqueue index
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 *
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 * The VhostUserHostNotifier entries are re-used. When an old mapping
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 * is to be released it is moved to @unmap_addr and @addr is replaced.
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 * Once the RCU process has completed the unmap @unmap_addr is
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 * cleared.
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 */
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typedef struct VhostUserHostNotifier {
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    struct rcu_head rcu;
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    MemoryRegion mr;
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    void *addr;
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    void *unmap_addr;
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    int idx;
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} VhostUserHostNotifier;
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/**
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 * VhostUserState - shared state for all vhost-user devices
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 * @chr: the character backend for the socket
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 * @notifiers: GPtrArray of @VhostUserHostnotifier
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 * @memory_slots:
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 */
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typedef struct VhostUserState {
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    CharBackend *chr;
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    GPtrArray *notifiers;
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    int memory_slots;
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    bool supports_config;
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} VhostUserState;
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/**
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 * vhost_user_init() - initialise shared vhost_user state
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 * @user: allocated area for storing shared state
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 * @chr: the chardev for the vhost socket
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 * @errp: error handle
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 *
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 * User can either directly g_new() space for the state or embed
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 * VhostUserState in their larger device structure and just point to
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 * it.
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 *
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 * Return: true on success, false on error while setting errp.
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 */
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bool vhost_user_init(VhostUserState *user, CharBackend *chr, Error **errp);
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/**
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 * vhost_user_cleanup() - cleanup state
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 * @user: ptr to use state
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 *
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 * Cleans up shared state and notifiers, callee is responsible for
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 * freeing the @VhostUserState memory itself.
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 */
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void vhost_user_cleanup(VhostUserState *user);
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/**
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 * vhost_user_async_close() - cleanup vhost-user post connection drop
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 * @d: DeviceState for the associated device (passed to callback)
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 * @chardev: the CharBackend associated with the connection
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 * @vhost: the common vhost device
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 * @cb: the user callback function to complete the clean-up
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 *
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 * This function is used to handle the shutdown of a vhost-user
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 * connection to a backend. We handle this centrally to make sure we
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 * do all the steps and handle potential races due to VM shutdowns.
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 * Once the connection is disabled we call a backhalf to ensure
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 */
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typedef void (*vu_async_close_fn)(DeviceState *cb);
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void vhost_user_async_close(DeviceState *d,
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                            CharBackend *chardev, struct vhost_dev *vhost,
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                            vu_async_close_fn cb);
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#endif
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