usb: cancel async packets on unplug

This patch adds USBBusOps struct with (for now) only a single callback
which is called when a device is about to be destroyed.  The USB Host
adapters are implementing this callback and use it to cancel any async
requests which might be in flight before the device actually goes away.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

7 files changed, 106 insertions, 7 deletions

diff --git a/hw/milkymist-softusb.c b/hw/milkymist-softusb.c
index 1565260..028f3b7 100644
--- a/hw/milkymist-softusb.c
+++ b/hw/milkymist-softusb.c
@@ -247,10 +247,18 @@ static void softusb_attach(USBPort *port)
 {
 }
 
+static void softusb_device_destroy(USBBus *bus, USBDevice *dev)
+{
+}
+
 static USBPortOps softusb_ops = {
     .attach = softusb_attach,
 };
 
+static USBBusOps softusb_bus_ops = {
+    .device_destroy = softusb_device_destroy,
+};
+
 static void milkymist_softusb_reset(DeviceState *d)
 {
     MilkymistSoftUsbState *s =
@@ -294,7 +302,7 @@ static int milkymist_softusb_init(SysBusDevice *dev)
     qemu_add_mouse_event_handler(softusb_mouse_event, s, 0, "Milkymist Mouse");
 
     /* create our usb bus */
-    usb_bus_new(&s->usbbus, NULL);
+    usb_bus_new(&s->usbbus, &softusb_bus_ops, NULL);
 
     /* our two ports */
     usb_register_port(&s->usbbus, &s->usbport[0], NULL, 0, &softusb_ops,
diff --git a/hw/usb-bus.c b/hw/usb-bus.c
index abc7e61..874c253 100644
--- a/hw/usb-bus.c
+++ b/hw/usb-bus.c
@@ -39,9 +39,10 @@ const VMStateDescription vmstate_usb_device = {
     }
 };
 
-void usb_bus_new(USBBus *bus, DeviceState *host)
+void usb_bus_new(USBBus *bus, USBBusOps *ops, DeviceState *host)
 {
     qbus_create_inplace(&bus->qbus, &usb_bus_info, host, NULL);
+    bus->ops = ops;
     bus->busnr = next_usb_bus++;
     bus->qbus.allow_hotplug = 1; /* Yes, we can */
     QTAILQ_INIT(&bus->free);
@@ -81,8 +82,10 @@ static int usb_qdev_init(DeviceState *qdev, DeviceInfo *base)
 static int usb_qdev_exit(DeviceState *qdev)
 {
     USBDevice *dev = DO_UPCAST(USBDevice, qdev, qdev);
+    USBBus *bus = usb_bus_from_device(dev);
 
     usb_device_detach(dev);
+    bus->ops->device_destroy(bus, dev);
     if (dev->info->handle_destroy) {
         dev->info->handle_destroy(dev);
     }
diff --git a/hw/usb-ehci.c b/hw/usb-ehci.c
index dd2752d..9051571 100644
--- a/hw/usb-ehci.c
+++ b/hw/usb-ehci.c
@@ -685,6 +685,18 @@ static void ehci_queues_rip_unused(EHCIState *ehci)
     }
 }
 
+static void ehci_queues_rip_device(EHCIState *ehci, USBDevice *dev)
+{
+    EHCIQueue *q, *tmp;
+
+    QTAILQ_FOREACH_SAFE(q, &ehci->queues, next, tmp) {
+        if (q->packet.owner != dev) {
+            continue;
+        }
+        ehci_free_queue(q);
+    }
+}
+
 static void ehci_queues_rip_all(EHCIState *ehci)
 {
     EHCIQueue *q, *tmp;
@@ -2100,6 +2112,13 @@ static void ehci_map(PCIDevice *pci_dev, int region_num,
     cpu_register_physical_memory(addr, size, s->mem);
 }
 
+static void ehci_device_destroy(USBBus *bus, USBDevice *dev)
+{
+    EHCIState *s = container_of(bus, EHCIState, bus);
+
+    ehci_queues_rip_device(s, dev);
+}
+
 static int usb_ehci_initfn(PCIDevice *dev);
 
 static USBPortOps ehci_port_ops = {
@@ -2108,6 +2127,10 @@ static USBPortOps ehci_port_ops = {
     .complete = ehci_async_complete_packet,
 };
 
+static USBBusOps ehci_bus_ops = {
+    .device_destroy = ehci_device_destroy,
+};
+
 static PCIDeviceInfo ehci_info = {
     .qdev.name    = "usb-ehci",
     .qdev.size    = sizeof(EHCIState),
@@ -2170,7 +2193,7 @@ static int usb_ehci_initfn(PCIDevice *dev)
 
     s->irq = s->dev.irq[3];
 
-    usb_bus_new(&s->bus, &s->dev.qdev);
+    usb_bus_new(&s->bus, &ehci_bus_ops, &s->dev.qdev);
     for(i = 0; i < NB_PORTS; i++) {
         usb_register_port(&s->bus, &s->ports[i], s, i, &ehci_port_ops,
                           USB_SPEED_MASK_HIGH);
diff --git a/hw/usb-musb.c b/hw/usb-musb.c
index 6037193..21f35afa 100644
--- a/hw/usb-musb.c
+++ b/hw/usb-musb.c
@@ -262,6 +262,7 @@
 static void musb_attach(USBPort *port);
 static void musb_detach(USBPort *port);
 static void musb_schedule_cb(USBDevice *dev, USBPacket *p);
+static void musb_device_destroy(USBBus *bus, USBDevice *dev);
 
 static USBPortOps musb_port_ops = {
     .attach = musb_attach,
@@ -269,6 +270,10 @@ static USBPortOps musb_port_ops = {
     .complete = musb_schedule_cb,
 };
 
+static USBBusOps musb_bus_ops = {
+    .device_destroy = musb_device_destroy,
+};
+
 typedef struct MUSBPacket MUSBPacket;
 typedef struct MUSBEndPoint MUSBEndPoint;
 
@@ -361,7 +366,7 @@ struct MUSBState *musb_init(qemu_irq *irqs)
         s->ep[i].epnum = i;
     }
 
-    usb_bus_new(&s->bus, NULL /* FIXME */);
+    usb_bus_new(&s->bus, &musb_bus_ops, NULL /* FIXME */);
     usb_register_port(&s->bus, &s->port, s, 0, &musb_port_ops,
                       USB_SPEED_MASK_LOW | USB_SPEED_MASK_FULL);
     usb_port_location(&s->port, NULL, 1);
@@ -778,6 +783,22 @@ static void musb_rx_packet_complete(USBPacket *packey, void *opaque)
     musb_rx_intr_set(s, epnum, 1);
 }
 
+static void musb_device_destroy(USBBus *bus, USBDevice *dev)
+{
+    MUSBState *s = container_of(bus, MUSBState, bus);
+    int ep, dir;
+
+    for (ep = 0; ep < 16; ep++) {
+        for (dir = 0; dir < 2; dir++) {
+            if (s->ep[ep].packey[dir].p.owner != dev) {
+                continue;
+            }
+            usb_cancel_packet(&s->ep[ep].packey[dir].p);
+            /* status updates needed here? */
+        }
+    }
+}
+
 static void musb_tx_rdy(MUSBState *s, int epnum)
 {
     MUSBEndPoint *ep = s->ep + epnum;
diff --git a/hw/usb-ohci.c b/hw/usb-ohci.c
index 8b966f7..401045a 100644
--- a/hw/usb-ohci.c
+++ b/hw/usb-ohci.c
@@ -1644,6 +1644,16 @@ static void ohci_mem_write(void *ptr, target_phys_addr_t addr, uint32_t val)
     }
 }
 
+static void ohci_device_destroy(USBBus *bus, USBDevice *dev)
+{
+    OHCIState *ohci = container_of(bus, OHCIState, bus);
+
+    if (ohci->async_td && ohci->usb_packet.owner == dev) {
+        usb_cancel_packet(&ohci->usb_packet);
+        ohci->async_td = 0;
+    }
+}
+
 /* Only dword reads are defined on OHCI register space */
 static CPUReadMemoryFunc * const ohci_readfn[3]={
     ohci_mem_read,
@@ -1664,6 +1674,10 @@ static USBPortOps ohci_port_ops = {
     .complete = ohci_async_complete_packet,
 };
 
+static USBBusOps ohci_bus_ops = {
+    .device_destroy = ohci_device_destroy,
+};
+
 static void usb_ohci_init(OHCIState *ohci, DeviceState *dev,
                           int num_ports, uint32_t localmem_base)
 {
@@ -1691,7 +1705,7 @@ static void usb_ohci_init(OHCIState *ohci, DeviceState *dev,
 
     ohci->name = dev->info->name;
 
-    usb_bus_new(&ohci->bus, dev);
+    usb_bus_new(&ohci->bus, &ohci_bus_ops, dev);
     ohci->num_ports = num_ports;
     for (i = 0; i < num_ports; i++) {
         usb_register_port(&ohci->bus, &ohci->rhport[i].port, ohci, i, &ohci_port_ops,
diff --git a/hw/usb-uhci.c b/hw/usb-uhci.c
index c0de05b..8f504d1 100644
--- a/hw/usb-uhci.c
+++ b/hw/usb-uhci.c
@@ -234,6 +234,19 @@ static void uhci_async_validate_end(UHCIState *s)
     }
 }
 
+static void uhci_async_cancel_device(UHCIState *s, USBDevice *dev)
+{
+    UHCIAsync *curr, *n;
+
+    QTAILQ_FOREACH_SAFE(curr, &s->async_pending, next, n) {
+        if (curr->packet.owner != dev) {
+            continue;
+        }
+        uhci_async_unlink(s, curr);
+        uhci_async_cancel(s, curr);
+    }
+}
+
 static void uhci_async_cancel_all(UHCIState *s)
 {
     UHCIAsync *curr, *n;
@@ -1081,6 +1094,13 @@ static void uhci_map(PCIDevice *pci_dev, int region_num,
     register_ioport_read(addr, 32, 1, uhci_ioport_readb, s);
 }
 
+static void uhci_device_destroy(USBBus *bus, USBDevice *dev)
+{
+    UHCIState *s = container_of(bus, UHCIState, bus);
+
+    uhci_async_cancel_device(s, dev);
+}
+
 static USBPortOps uhci_port_ops = {
     .attach = uhci_attach,
     .detach = uhci_detach,
@@ -1088,6 +1108,10 @@ static USBPortOps uhci_port_ops = {
     .complete = uhci_async_complete,
 };
 
+static USBBusOps uhci_bus_ops = {
+    .device_destroy = uhci_device_destroy,
+};
+
 static int usb_uhci_common_initfn(UHCIState *s)
 {
     uint8_t *pci_conf = s->dev.config;
@@ -1100,7 +1124,7 @@ static int usb_uhci_common_initfn(UHCIState *s)
     pci_conf[PCI_INTERRUPT_PIN] = 4; // interrupt pin 3
     pci_conf[0x60] = 0x10; // release number
 
-    usb_bus_new(&s->bus, &s->dev.qdev);
+    usb_bus_new(&s->bus, &uhci_bus_ops, &s->dev.qdev);
     for(i = 0; i < NB_PORTS; i++) {
         usb_register_port(&s->bus, &s->ports[i].port, s, i, &uhci_port_ops,
                           USB_SPEED_MASK_LOW | USB_SPEED_MASK_FULL);
diff --git a/hw/usb.h b/hw/usb.h
index 9882400..6097208 100644
--- a/hw/usb.h
+++ b/hw/usb.h
@@ -132,6 +132,7 @@
 #define USB_ENDPOINT_XFER_INT		3
 
 typedef struct USBBus USBBus;
+typedef struct USBBusOps USBBusOps;
 typedef struct USBPort USBPort;
 typedef struct USBDevice USBDevice;
 typedef struct USBDeviceInfo USBDeviceInfo;
@@ -323,6 +324,7 @@ void musb_set_size(MUSBState *s, int epnum, int size, int is_tx);
 
 struct USBBus {
     BusState qbus;
+    USBBusOps *ops;
     int busnr;
     int nfree;
     int nused;
@@ -331,7 +333,11 @@ struct USBBus {
     QTAILQ_ENTRY(USBBus) next;
 };
 
-void usb_bus_new(USBBus *bus, DeviceState *host);
+struct USBBusOps {
+    void (*device_destroy)(USBBus *bus, USBDevice *dev);
+};
+
+void usb_bus_new(USBBus *bus, USBBusOps *ops, DeviceState *host);
 USBBus *usb_bus_find(int busnr);
 void usb_qdev_register(USBDeviceInfo *info);
 void usb_qdev_register_many(USBDeviceInfo *info);