From 9561fda8d90e176bef598ba87c42a1bd6ad03ef7 Mon Sep 17 00:00:00 2001 From: Stefan Hajnoczi Date: Wed, 19 Mar 2014 08:58:55 +0100 Subject: qom: Make QOM link property unref optional MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Some object_property_add_link() callers expect property deletion to unref the link property object. Other callers expect to manage the refcount themselves. The former are currently broken and therefore leak the link property object. This patch adds a flags argument to object_property_add_link() so the caller can specify which refcount behavior they require. The new OBJ_PROP_LINK_UNREF_ON_RELEASE flag causes the link pointer to be unreferenced when the property is deleted. This fixes refcount leaks in qdev.c, xilinx_axidma.c, xilinx_axienet.c, s390-virtio-bus.c, virtio-pci.c, virtio-rng.c, and ui/console.c. Rationale for refcount behavior: * hw/core/qdev.c - bus children are explicitly unreferenced, don't interfere - parent_bus is essentially a read-only property that doesn't hold a refcount, don't unref - hotplug_handler is leaked, do unref * hw/dma/xilinx_axidma.c - rx stream "dma" links are set using set_link, therefore they need unref - tx streams are set using set_link, therefore they need unref * hw/net/xilinx_axienet.c - same reasoning as hw/dma/xilinx_axidma.c * hw/pcmcia/pxa2xx.c - pxa2xx bypasses set_link and therefore does not use refcounts * hw/s390x/s390-virtio-bus.c * hw/virtio/virtio-pci.c * hw/virtio/virtio-rng.c * ui/console.c - set_link is used and there is no explicit unref, do unref Cc: Peter Crosthwaite Cc: Alexander Graf Cc: Anthony Liguori Cc: "Michael S. Tsirkin" Signed-off-by: Stefan Hajnoczi Reviewed-by: Paolo Bonzini Signed-off-by: Andreas Färber --- ui/console.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'ui') diff --git a/ui/console.c b/ui/console.c index 4df251d..9974212 100644 --- a/ui/console.c +++ b/ui/console.c @@ -1180,7 +1180,9 @@ static QemuConsole *new_console(DisplayState *ds, console_type_t console_type) obj = object_new(TYPE_QEMU_CONSOLE); s = QEMU_CONSOLE(obj); object_property_add_link(obj, "device", TYPE_DEVICE, - (Object **)&s->device, &local_err); + (Object **)&s->device, + OBJ_PROP_LINK_UNREF_ON_RELEASE, + &local_err); object_property_add_uint32_ptr(obj, "head", &s->head, &local_err); -- cgit v1.1 From 39f72ef94ba74701d18daf82b44c18a60f94eb60 Mon Sep 17 00:00:00 2001 From: Stefan Hajnoczi Date: Wed, 19 Mar 2014 08:58:56 +0100 Subject: qom: Add check() argument to object_property_add_link() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit There are currently three types of object_property_add_link() callers: 1. The link property may be set at any time. 2. The link property of a DeviceState instance may only be set before realize. 3. The link property may never be set, it is read-only. Something similar can already be achieved with object_property_add_str()'s set() argument. Follow its example and add a check() argument to object_property_add_link(). Also provide default check() functions for case #1 and #2. Case #3 is covered by passing a NULL function pointer. Cc: Peter Crosthwaite Cc: Alexander Graf Cc: Anthony Liguori Cc: "Michael S. Tsirkin" Signed-off-by: Stefan Hajnoczi Reviewed-by: Paolo Bonzini [AF: Tweaked documentation comment] Signed-off-by: Andreas Färber --- ui/console.c | 1 + 1 file changed, 1 insertion(+) (limited to 'ui') diff --git a/ui/console.c b/ui/console.c index 9974212..e057755 100644 --- a/ui/console.c +++ b/ui/console.c @@ -1181,6 +1181,7 @@ static QemuConsole *new_console(DisplayState *ds, console_type_t console_type) s = QEMU_CONSOLE(obj); object_property_add_link(obj, "device", TYPE_DEVICE, (Object **)&s->device, + object_property_allow_set_link, OBJ_PROP_LINK_UNREF_ON_RELEASE, &local_err); object_property_add_uint32_ptr(obj, "head", -- cgit v1.1