usb: Add an usb_device_ep_stopped USBDevice method

Some usb devices (host or network redirection) can benefit from knowing when
the guest stops using an endpoint. Redirection may involve submitting packets
independently from the guest (in combination with a fifo buffer between the
redirection code and the guest), to ensure that buffers of the real usb device
are timely emptied. This is done for example for isoc traffic and for interrupt
input endpoints. But when the (re)submission of packets is done by the device
code, then how does it know when to stop this?

For isoc endpoints this is handled by detecting a set interface (change alt
setting) command, which works well for isoc endpoints. But for interrupt
endpoints currently the redirection code never stops receiving data from
the device, which is less then ideal.

However the controller emulation is aware when a guest looses interest, as
then the qh for the endpoint gets unlinked (ehci, ohci, uhci) or the endpoint
is explicitly stopped (xhci). This patch adds a new ep_stopped USBDevice
method and modifies the hcd code to call this on queue unlink / ep stop.

This makes it possible for the redirection code to properly stop receiving
interrupt input (*) data when the guest no longer has interest in it.

*) And in the future also buffered bulk input.

Signed-off-by: Hans de Goede <[email protected]>
Signed-off-by: Gerd Hoffmann <[email protected]>

diff --git a/hw/usb.h b/hw/usb.h
index 81e265c4fd101b308b8839b4bf1a438b8fa32411..aca8ff695080fb499963fa809e824c575d7cd8d9 100644 (file)
--- a/hw/usb.h
+++ b/hw/usb.h
@@ -307,6 +307,12 @@ typedef struct USBDeviceClass {
      */
     void (*flush_ep_queue)(USBDevice *dev, USBEndpoint *ep);
 
+    /*
+     * Called by the hcd to let the device know the queue for an endpoint
+     * has been unlinked / stopped. Optional may be NULL.
+     */
+    void (*ep_stopped)(USBDevice *dev, USBEndpoint *ep);
+
     const char *product_desc;
     const USBDesc *usb_desc;
 } USBDeviceClass;
@@ -539,6 +545,8 @@ void usb_device_set_interface(USBDevice *dev, int interface,
 
 void usb_device_flush_ep_queue(USBDevice *dev, USBEndpoint *ep);
 
+void usb_device_ep_stopped(USBDevice *dev, USBEndpoint *ep);
+
 const char *usb_device_get_product_desc(USBDevice *dev);
 
 const USBDesc *usb_device_get_usb_desc(USBDevice *dev);

diff --git a/hw/usb/bus.c b/hw/usb/bus.c
index 10260a13ac2f1b46439c0f725b6d3da932885919..180d1d739bf57a56ddf49570ecede635b0304114 100644 (file)
--- a/hw/usb/bus.c
+++ b/hw/usb/bus.c
@@ -189,6 +189,14 @@ void usb_device_flush_ep_queue(USBDevice *dev, USBEndpoint *ep)
     }
 }
 
+void usb_device_ep_stopped(USBDevice *dev, USBEndpoint *ep)
+{
+    USBDeviceClass *klass = USB_DEVICE_GET_CLASS(dev);
+    if (klass->ep_stopped) {
+        klass->ep_stopped(dev, ep);
+    }
+}
+
 static int usb_qdev_init(DeviceState *qdev)
 {
     USBDevice *dev = USB_DEVICE(qdev);

diff --git a/hw/usb/hcd-ehci.c b/hw/usb/hcd-ehci.c
index 1713394c6547a230bb996e49df9b95c49db96758..320b7e72393ef5d5b9446bd91f5ee76b6abce280 100644 (file)
--- a/hw/usb/hcd-ehci.c
+++ b/hw/usb/hcd-ehci.c
@@ -622,6 +622,17 @@ static EHCIQueue *ehci_alloc_queue(EHCIState *ehci, uint32_t addr, int async)
     return q;
 }
 
+static void ehci_queue_stopped(EHCIQueue *q)
+{
+    int endp  = get_field(q->qh.epchar, QH_EPCHAR_EP);
+
+    if (!q->last_pid || !q->dev) {
+        return;
+    }
+
+    usb_device_ep_stopped(q->dev, usb_ep_get(q->dev, q->last_pid, endp));
+}
+
 static int ehci_cancel_queue(EHCIQueue *q)
 {
     EHCIPacket *p;
@@ -629,7 +640,7 @@ static int ehci_cancel_queue(EHCIQueue *q)
 
     p = QTAILQ_FIRST(&q->packets);
     if (p == NULL) {
-        return 0;
+        goto leave;
     }
 
     trace_usb_ehci_queue_action(q, "cancel");
@@ -637,6 +648,9 @@ static int ehci_cancel_queue(EHCIQueue *q)
         ehci_free_packet(p);
         packets++;
     } while ((p = QTAILQ_FIRST(&q->packets)) != NULL);
+
+leave:
+    ehci_queue_stopped(q);
     return packets;
 }
 
@@ -1392,6 +1406,9 @@ static int ehci_execute(EHCIPacket *p, const char *action)
         return -1;
     }
 
+    if (!ehci_verify_pid(p->queue, &p->qtd)) {
+        ehci_queue_stopped(p->queue); /* Mark the ep in the prev dir stopped */
+    }
     p->pid = ehci_get_pid(&p->qtd);
     p->queue->last_pid = p->pid;
     endp = get_field(p->queue->qh.epchar, QH_EPCHAR_EP);

diff --git a/hw/usb/hcd-ohci.c b/hw/usb/hcd-ohci.c
index 052c4a3037f2c0416a707e2137f7036ab2b0ef77..29bafa6da9d9f1e029d824e1cc87e2aa524cfff5 100644 (file)
--- a/hw/usb/hcd-ohci.c
+++ b/hw/usb/hcd-ohci.c
@@ -430,6 +430,23 @@ static USBDevice *ohci_find_device(OHCIState *ohci, uint8_t addr)
     return NULL;
 }
 
+static void ohci_stop_endpoints(OHCIState *ohci)
+{
+    USBDevice *dev;
+    int i, j;
+
+    for (i = 0; i < ohci->num_ports; i++) {
+        dev = ohci->rhport[i].port.dev;
+        if (dev && dev->attached) {
+            usb_device_ep_stopped(dev, &dev->ep_ctl);
+            for (j = 0; j < USB_MAX_ENDPOINTS; j++) {
+                usb_device_ep_stopped(dev, &dev->ep_in[j]);
+                usb_device_ep_stopped(dev, &dev->ep_out[j]);
+            }
+        }
+    }
+}
+
 /* Reset the controller */
 static void ohci_reset(void *opaque)
 {
@@ -478,6 +495,7 @@ static void ohci_reset(void *opaque)
         usb_cancel_packet(&ohci->usb_packet);
         ohci->async_td = 0;
     }
+    ohci_stop_endpoints(ohci);
     DPRINTF("usb-ohci: Reset %s\n", ohci->name);
 }
 
@@ -1147,6 +1165,8 @@ static int ohci_service_ed_list(OHCIState *ohci, uint32_t head, int completion)
             if (ohci->async_td && addr == ohci->async_td) {
                 usb_cancel_packet(&ohci->usb_packet);
                 ohci->async_td = 0;
+                usb_device_ep_stopped(ohci->usb_packet.ep->dev,
+                                      ohci->usb_packet.ep);
             }
             continue;
         }
@@ -1227,10 +1247,12 @@ static void ohci_frame_boundary(void *opaque)
     }
 
     /* Cancel all pending packets if either of the lists has been disabled.  */
-    if (ohci->async_td &&
-        ohci->old_ctl & (~ohci->ctl) & (OHCI_CTL_BLE | OHCI_CTL_CLE)) {
-        usb_cancel_packet(&ohci->usb_packet);
-        ohci->async_td = 0;
+    if (ohci->old_ctl & (~ohci->ctl) & (OHCI_CTL_BLE | OHCI_CTL_CLE)) {
+        if (ohci->async_td) {
+            usb_cancel_packet(&ohci->usb_packet);
+            ohci->async_td = 0;
+        }
+        ohci_stop_endpoints(ohci);
     }
     ohci->old_ctl = ohci->ctl;
     ohci_process_lists(ohci, 0);

diff --git a/hw/usb/hcd-uhci.c b/hw/usb/hcd-uhci.c
index bd3377e36a7fdffa6f0721e5fd8715e5a06ac491..0cd68cf3557aaff6c64fd3d8a759082ad0e97d3e 100644 (file)
--- a/hw/usb/hcd-uhci.c
+++ b/hw/usb/hcd-uhci.c
@@ -226,6 +226,7 @@ static void uhci_queue_free(UHCIQueue *queue, const char *reason)
         async = QTAILQ_FIRST(&queue->asyncs);
         uhci_async_cancel(async);
     }
+    usb_device_ep_stopped(queue->ep->dev, queue->ep);
 
     trace_usb_uhci_queue_del(queue->token, reason);
     QTAILQ_REMOVE(&s->queues, queue, next);

diff --git a/hw/usb/hcd-xhci.c b/hw/usb/hcd-xhci.c
index e2de71ef1a940da136104f7351634c0903bbbace..40542b8d05078cbc3b82f4100b3d333ae4181bed 100644 (file)
--- a/hw/usb/hcd-xhci.c
+++ b/hw/usb/hcd-xhci.c
@@ -1177,6 +1177,7 @@ static int xhci_ep_nuke_xfers(XHCIState *xhci, unsigned int slotid,
     XHCISlot *slot;
     XHCIEPContext *epctx;
     int i, xferi, killed = 0;
+    USBEndpoint *ep = NULL;
     assert(slotid >= 1 && slotid <= xhci->numslots);
     assert(epid >= 1 && epid <= 31);
 
@@ -1192,9 +1193,15 @@ static int xhci_ep_nuke_xfers(XHCIState *xhci, unsigned int slotid,
 
     xferi = epctx->next_xfer;
     for (i = 0; i < TD_QUEUE; i++) {
+        if (epctx->transfers[xferi].packet.ep) {
+            ep = epctx->transfers[xferi].packet.ep;
+        }
         killed += xhci_ep_nuke_one_xfer(&epctx->transfers[xferi]);
         xferi = (xferi + 1) % TD_QUEUE;
     }
+    if (ep) {
+        usb_device_ep_stopped(ep->dev, ep);
+    }
     return killed;
 }