diff options
| -rw-r--r-- | block/export/vhost-user-blk-server.c | 13 | ||||
| -rw-r--r-- | include/qemu/vhost-user-server.h | 4 | ||||
| -rw-r--r-- | util/vhost-user-server.c | 18 |
3 files changed, 28 insertions, 7 deletions
diff --git a/block/export/vhost-user-blk-server.c b/block/export/vhost-user-blk-server.c index 841acb36e3..f51a36a14f 100644 --- a/block/export/vhost-user-blk-server.c +++ b/block/export/vhost-user-blk-server.c @@ -272,7 +272,20 @@ static void vu_blk_exp_resize(void *opaque) vu_config_change_msg(&vexp->vu_server.vu_dev); } +/* + * Ensures that bdrv_drained_begin() waits until in-flight requests complete. + * + * Called with vexp->export.ctx acquired. + */ +static bool vu_blk_drained_poll(void *opaque) +{ + VuBlkExport *vexp = opaque; + + return vhost_user_server_has_in_flight(&vexp->vu_server); +} + static const BlockDevOps vu_blk_dev_ops = { + .drained_poll = vu_blk_drained_poll, .resize_cb = vu_blk_exp_resize, }; diff --git a/include/qemu/vhost-user-server.h b/include/qemu/vhost-user-server.h index bc0ac9ddb6..b1c1cda886 100644 --- a/include/qemu/vhost-user-server.h +++ b/include/qemu/vhost-user-server.h @@ -40,8 +40,9 @@ typedef struct { int max_queues; const VuDevIface *vu_iface; + unsigned int in_flight; /* atomic */ + /* Protected by ctx lock */ - unsigned int in_flight; bool wait_idle; VuDev vu_dev; QIOChannel *ioc; /* The I/O channel with the client */ @@ -62,6 +63,7 @@ void vhost_user_server_stop(VuServer *server); void vhost_user_server_inc_in_flight(VuServer *server); void vhost_user_server_dec_in_flight(VuServer *server); +bool vhost_user_server_has_in_flight(VuServer *server); void vhost_user_server_attach_aio_context(VuServer *server, AioContext *ctx); void vhost_user_server_detach_aio_context(VuServer *server); diff --git a/util/vhost-user-server.c b/util/vhost-user-server.c index 1622f8cfb3..68c3bf162f 100644 --- a/util/vhost-user-server.c +++ b/util/vhost-user-server.c @@ -78,17 +78,23 @@ static void panic_cb(VuDev *vu_dev, const char *buf) void vhost_user_server_inc_in_flight(VuServer *server) { assert(!server->wait_idle); - server->in_flight++; + qatomic_inc(&server->in_flight); } void vhost_user_server_dec_in_flight(VuServer *server) { - server->in_flight--; - if (server->wait_idle && !server->in_flight) { - aio_co_wake(server->co_trip); + if (qatomic_fetch_dec(&server->in_flight) == 1) { + if (server->wait_idle) { + aio_co_wake(server->co_trip); + } } } +bool vhost_user_server_has_in_flight(VuServer *server) +{ + return qatomic_load_acquire(&server->in_flight) > 0; +} + static bool coroutine_fn vu_message_read(VuDev *vu_dev, int conn_fd, VhostUserMsg *vmsg) { @@ -192,13 +198,13 @@ static coroutine_fn void vu_client_trip(void *opaque) /* Keep running */ } - if (server->in_flight) { + if (vhost_user_server_has_in_flight(server)) { /* Wait for requests to complete before we can unmap the memory */ server->wait_idle = true; qemu_coroutine_yield(); server->wait_idle = false; } - assert(server->in_flight == 0); + assert(!vhost_user_server_has_in_flight(server)); vu_deinit(vu_dev); |