1 /* 2 * Sharing QEMU devices via vhost-user protocol 3 * 4 * Copyright (c) Coiby Xu <coiby.xu@gmail.com>. 5 * Copyright (c) 2020 Red Hat, Inc. 6 * 7 * This work is licensed under the terms of the GNU GPL, version 2 or 8 * later. See the COPYING file in the top-level directory. 9 */ 10 11 #ifndef VHOST_USER_SERVER_H 12 #define VHOST_USER_SERVER_H 13 14 #include "subprojects/libvhost-user/libvhost-user.h" /* only for the type definitions */ 15 #include "io/channel-socket.h" 16 #include "io/channel-file.h" 17 #include "io/net-listener.h" 18 #include "qapi/error.h" 19 #include "standard-headers/linux/virtio_blk.h" 20 21 /* A kick fd that we monitor on behalf of libvhost-user */ 22 typedef struct VuFdWatch { 23 VuDev *vu_dev; 24 int fd; /*kick fd*/ 25 void *pvt; 26 vu_watch_cb cb; 27 QTAILQ_ENTRY(VuFdWatch) next; 28 } VuFdWatch; 29 30 /** 31 * VuServer: 32 * A vhost-user server instance with user-defined VuDevIface callbacks. 33 * Vhost-user device backends can be implemented using VuServer. VuDevIface 34 * callbacks and virtqueue kicks run in the given AioContext. 35 */ 36 typedef struct { 37 QIONetListener *listener; 38 QEMUBH *restart_listener_bh; 39 AioContext *ctx; 40 int max_queues; 41 const VuDevIface *vu_iface; 42 43 unsigned int in_flight; /* atomic */ 44 45 /* Protected by ctx lock */ 46 bool wait_idle; 47 VuDev vu_dev; 48 QIOChannel *ioc; /* The I/O channel with the client */ 49 QIOChannelSocket *sioc; /* The underlying data channel with the client */ 50 QTAILQ_HEAD(, VuFdWatch) vu_fd_watches; 51 52 Coroutine *co_trip; /* coroutine for processing VhostUserMsg */ 53 } VuServer; 54 55 bool vhost_user_server_start(VuServer *server, 56 SocketAddress *unix_socket, 57 AioContext *ctx, 58 uint16_t max_queues, 59 const VuDevIface *vu_iface, 60 Error **errp); 61 62 void vhost_user_server_stop(VuServer *server); 63 64 void vhost_user_server_inc_in_flight(VuServer *server); 65 void vhost_user_server_dec_in_flight(VuServer *server); 66 bool vhost_user_server_has_in_flight(VuServer *server); 67 68 void vhost_user_server_attach_aio_context(VuServer *server, AioContext *ctx); 69 void vhost_user_server_detach_aio_context(VuServer *server); 70 71 #endif /* VHOST_USER_SERVER_H */ 72